Cornice fastening unit. Roof eaves installation: design features and installation. Ventilation system design

Warning: Use of undefined constant WPLANG - assumed "WPLANG" (this will throw an Error in a future version of PHP) in /var/www/krysha-expert..php on line 2580

Warning: count(): Parameter must be an array or an object that implements Countable in /var/www/krysha-expert..php on line 1802

The construction of a roof consists of several stages, each of which is important in its own way. All of them have a great impact on the durability and operational efficiency of the structure. Let's consider the construction of a cornice overhang, which is a mandatory element of most rafter systems.

The eaves overhang is the part of the slope that protrudes beyond the front walls of the building and is designed to remove moisture from the frame and improve the appearance. The minimum overhang is 50–60 cm, but these values can vary widely depending on the building traditions in the area. For example, some house designs in Finland use a cornice overhang as a canopy for the veranda, and this is a fairly large structure that requires highly skilled builders.

The final design of the overhangs depends only on the wishes of the developer. It does not have any effect on functionality, but only if all recommendations of building codes and regulations are strictly followed.

Table. Types of eaves structures

Overhang type	Short description
	The simplest design, most often used on uninsulated roofs. The rafter legs are not sheathed; only a cornice board or metal strip is used to protect the ends from moisture. The fillies are covered with continuous lathing. This option is recommended for use on roofs with soft roofs or flat structures.
	A more complex and beautiful overhang completely protects the under-roof space from the penetration of moisture, birds and large insects. Currently, it is used not only as a structural element, but also as a decorative element, and can serve as a basis for the installation of lighting fixtures.

Before making a final choice, you should consult with professionals, taking into account the appearance and the need to ensure the recommended operating conditions of the roof.

Prices for various types of construction boards

Construction boards

Materials for filing

The finishing of eaves overhangs is carried out using various building materials, among which there are both budget and exclusive options. When choosing, it is recommended to take into account the style of the building and nearby buildings.

Siding. The most popular material at present. The main advantage is low price and ease of installation. Plastic panels are easy to cut and can be bent slightly if necessary. The industry offers customers special panels for filing, this is the so-called siding for eaves. Its difference from the ordinary one is the presence of perforated ventilation holes. Siding can be purchased in various sizes and colors.
Natural boards. The second most famous material, it is recommended for use on traditional wooden buildings. Boards must be impregnated with effective antiseptics and coated with durable varnishes or paints for outdoor use. For hemming, you can use clapboard, an ordinary edged board or a special hemming board. The technology presents no difficulties even for inexperienced builders. But during work, you should always remember about natural ventilation and leave air to ensure the movement of air flows.
Natural lining is an excellent option for hemming cornices
Cink Steel. Quite a good material for decorating overhangs, provided that the steel sheets are coated with decorative polymer paints. Metal panels can be purchased ready-made in a store or made independently from roofing sheets.
Copper. It is used very rarely, mostly on religious and historical buildings. But there are options for installing such cladding on prestigious country cottages.

Siding prices

How to make a cornice overhang correctly

Quite often, the ends of the rafters protrude slightly beyond the load-bearing walls and the eaves overhang turns out to be too narrow. In such cases, the rafters are extended using boards with a section of 100 by 50 mm. These elements are called fillies.

No wonder people have said since ancient times that the most important thing is a reliable roof over your head. Professional roofing craftsmen also confirm that only a reliable, durable roof ensures comfortable living in the house. Moreover, the reliability and durability of this complex structure sometimes depends on seemingly very insignificant elements.

For example, the roof cornice, despite its small size and percentage of the surface area of the slopes, this element performs important functions that affect the service life, insulating ability and strength of the roof. In this article we will talk about the design of the roof eaves of a house, methods of its formation and optimal dimensions.

The roof eaves are an important element of roofing structures; this term refers to the lower parts of the roof slopes, which are their continuation. Installation of cornices is carried out during the arrangement of the rafter system by increasing the length of the rafters or by installing fillies. On top, the cornice, like the entire area of the slope, is covered with roofing material, and from below it is sewn up using lumber, soffits, and siding. In the roof structure of a house, it performs the following functions:

Protects the walls of the house from moisture. The eaves overhang of the roof protects the upper part of the external walls from atmospheric moisture and dirt, maintaining their attractive appearance and integrity.
Prevents the flow of melt and rain water onto the foundation area. The structure of the roof eaves is such that it carries streams of water and blocks of snow sliding off the slope further from the foundation of the house, preventing erosion and destruction of the blind area.
Gives the roof a finished, neat look. Roof overhangs, being a continuation of the slope, give the structure a more proportional appearance, harmoniously completing the architectural design of the house.

Note! Installation of eaves is a mandatory stage of roofing work, which is required by the technology of roof construction, regardless of its type, shape and type of waterproofing coating. Even flat roofs have a slight projection, protruding beyond the outer walls of the structure.

Kinds

Many homeowners are interested in whether it is possible to design a roof cornice with their own hands, since visually its design seems extremely simple. Experienced craftsmen believe that this is a job that even a non-professional can do. The main thing is to understand the purpose and types of cornices. In the design of pitched roofs, the following 2 types of overhangs are distinguished:

Pedimental. The gable overhang is the part of the roof slope that protrudes beyond the outer walls of the house from the gable side. Typically, this type of cornice is short in length and is formed by the sheathing and fascia that gives it its shape.
Cornice. The eaves overhang or cornice is the lower part of the slope, starting from the intersection of the roof plane with the external load-bearing walls. These cornices are usually much larger than gable cornices as they prevent splashes of water flowing from the slope from hitting the wall finishing.

Important! In essence, the cornice is an extension of the rafter legs. Since the overhang is located at the bottom of the slope, it bears minimal snow load. However, the installation of a gutter or snow guards changes the distribution of loads, so significant pressure may be exerted on it.

Formation methods

Before you make a roof cornice, you need to understand the structure of this element of the roof structure, as well as the methods of its formation. The method of installing an overhang depends on the design and type of roof, and on the length of the slopes. The most common technologies that can be used to form a roofing cornice are:

Lengthening rafter legs. The easiest way to form a roof overhang is to use rafters that are longer than the size of the slope. The more overhang you want, the longer the bars from which the rafters are made should be. The disadvantage of this method is that it increases the weight of the frame and, consequently, the load on the foundation.
Extension of rafters using fillies. To form the roof cornice, you can extend the ends of the rafters using fillets - lighter and cheaper elements made from edged boards of lesser thickness. Thanks to the fillies, the frame has less weight, despite the large cornice.

Professional craftsmen consider it advisable to use fillies to form an overhang if the length of the slope exceeds the standard size of lumber. Typically, the length of the boards from which the roof frame is made is 6 meters. If the roof slope is 6 meters or more long, the installation of the cornice is carried out using fillies.

Optimal size

It is often difficult for non-professional craftsmen to determine what size cornice to make. This is indeed a very important design decision, because if it is too small, then melt or rain water from the slope will fall on the lining of the external walls, on the foundation blind area, leading to destruction and also damage to the appearance of the structure. When choosing the length of the cornice, the following factors are taken into account:

Climatic conditions. The optimal size of the roof eaves depends on the amount of precipitation falling in winter and summer. In snowier regions, roofs with wide eaves are traditionally used to protect the walls and foundation from snow. For example, alpine chalets located in the mountains usually have eaves overhangs at least 1 meter wide.
Roof slope. The greater the angle of inclination of the roof slopes, the smaller the cornice can be made. This is explained by the fact that with a flat roof shape, the trajectory of falling snow and water goes far from the outer walls of the house. If the slopes are steep enough, then it is better to make the cornices wider to protect the structure from splashes of water that can reach the wall during intense snowmelt or rainfall.
Proportions of the house. A wide cornice with a flat roof makes the building visually lower, squat, distorting the optimal proportions. A narrow overhang with a high, steep roof, on the contrary, elongates the silhouette of the house.

Important! The minimum permissible width of cornices is 45-50 cm, but this is clearly not enough for regions with high snow loads. If necessary, the size of this structural element is increased to 1 m.

Material for filing

Installation of overhangs is carried out at the final stage of work on assembling the rafter frame. When the sheathing is ready, the rafter legs are leveled, and then the frontal (wind) strip is fixed at their ends. To protect the lower surface from moisture penetration or bird colonization of the overhang, the cornice is hemmed. This task can be accomplished using various materials:

Remember that ventilation of the under-roof space is an important factor affecting the service life of the rafter frame. Therefore, experienced craftsmen recommend using soffits for filing overhangs. It is better to use models with central perforations that provide an average level of ventilation.

Binding methods

In order for the eaves overhang to not only perform its functions efficiently, but also to look aesthetically pleasing and neat, it must be properly hemmed. To do this, it is not enough to choose high-quality material; you also need to decide on the method of filing, which depends on the slope and length of the slope. There are two methods:

Diagonal hem. This method involves hemming the cornices using soffits so that they are parallel to the slopes. In this way, roofs with a large slope but a short slope length are hemmed. The diagonal method is considered more labor-intensive.
Straight hem. This option differs in that the roof eaves are covered with soffits using a box located at right angles to the outer wall of the structure. Direct hemming takes less time, but it is more expensive in terms of consumption of building materials.

Video instruction

Lining the roof is a mandatory step. As a result of such work, the house receives not only a pleasant appearance, but also additional protection from the effects of precipitation.

What it is?

Overhangs are protruding parts along the perimeter of the roof. The task is to protect the walls of the building from raindrops and other contaminants that can fall on the walls from the roof slopes. Overhangs can be of different sizes; traditionally their width ranges from 0.4-1 m. By and large, filing is not at all necessary. This is more due to overall aesthetics than functionality

Be that as it may, the binder performs several important tasks:

With its help you can protect the “filling” of the roofing pie from prying eyes. Nobody wants layers of waterproofing, insulation, or vapor barrier film to be visible.
Hemming prevents the wind from tearing off the roofing sheets. If the roof is not hemmed, a strong gust of wind can penetrate the ventilation gap and simply lift the roof, completely destroying it. So hemming can be considered mandatory in windy regions.

Hemming is carried out only at the very end of all finishing work, after complete cladding of not only the roof, but also the building itself has been completed. Professionals call lining the roof the final touch that gives the entire structure a finished look.

There are several varieties of both the stingrays themselves and the tailoring. Each hemming method is suitable for a specific slope, and you need to keep all these subtleties in mind. Analyze what kind of slope you are going to design, and only after that start making calculations, purchasing materials and other preparations. Also take into account the overall style concept of the house and decide whether hems are needed at all in your case.

Types of construction

Overhangs can be eaves or pediment. The cornices are located horizontally, and the pediments are located vertically. Keep in mind that gable overhangs are only hemmed in a certain way, since they are much more difficult to protect than horizontal ones.

The main purpose of eaves overhangs is to provide roof ventilation.

It is well known that it is necessary to leave gaps between the layers of the roof, otherwise they will not fully perform their functions and in many ways the roof will become ineffective. For example, if you do not provide the necessary space between the vapor barrier layer and the insulation, the insulation may become wet, moldy, and stop retaining heat. Having good ventilation is one of the main rules when constructing a roof.

Cornice overhangs can be simple or with extension. An ordinary overhang is easier to construct, but has several disadvantages, the main one of which is a booming sound that occurs every time a strong wind blows. When performing filing with removal, such troubles do not arise. It is possible to make ventilation through the eaves overhang in both the first and second cases. The presence of a take-out is not an obstacle. Pediment overhangs perform a protective function, protecting the walls of the building from atmospheric phenomena.

The overhang trim is a standard component of the unit, which is taken into account at the planning stage. It is worth noting that the knot options may be different, but each of them requires a hem.

Please note that they produce different types of roofs: mansard, flat, gable, hip. Whatever the roof, it must be hemmed to ensure not only the best aesthetic, but also functional performance. Not every option has pediment hems. For example, hipped or flat roofs require only eaves, since they do not have gables.

Right up to the rafters

Fitting overhangs directly along the rafters is the simplest method of installation. It is used primarily for roofs with small slope angles (up to 30 degrees). Even a beginner can perform such a binder.

The technology is as follows:

additional sheathing is made from bars or boards, along which the filing will be made in the future;
The sheathing is screwed to the rafters and placed parallel to the wall.

Keep in mind that the overhang must protrude beyond the walls by 40-50 cm. If the value is greater or less, it is preferable to choose a different method of filing.

If you wish and have some experience, you can position the sheathing perpendicular to the rafters, and not along them. However, it is important to ensure that the condition of parallelism to the wall is met. The sheathing can be directed slightly away from the wall to make the walls more secure, but the parallel arrangement is the reference.

An important condition is that the overhangs are in the same plane: if they fluctuate in height relative to the ground, then it is better to prefer another method of filing. In addition, it is much easier to hem even overhangs, because you do not have to assemble the hem from pieces. It will be enough to use a solid board or block.

To facilitate installation, experts advise using rope. So, first the corner elements of the overhangs are hemmed, then a rope is stretched between them, and further installation is carried out along it. Using the rope, you can immediately assess the evenness of the hems, their uniformity, and this greatly affects the overall aesthetics of the entire type of roof.

Horizontal

Horizontal sheathing is chosen in cases where the roof has steep slopes. It is in these situations that hemming looks harmonious and impressive. By and large, the horizontal filing is a box that is nailed along the eaves. Later it is edged with boards in a special way. This is done to prevent moisture from getting inside the box.

If the overhang is wider than 45 cm, then it must be further strengthened. For this purpose, additional beams are used that are laid in the middle of the box. So the lower part of the sheathing is nailed to this bar too, so the load on the overhangs themselves and the specially constructed sheathing is significantly reduced. There is a second point here: such fastening is necessary if the house is located in a windy area. A lining that is too wide can simply be blown away by the wind.

One of the intermediate stages of work is the installation of perpendicular beams. They are stuffed perpendicular to the wall. This is done to further strengthen the overhang, reduce the load, so that snow and wind effects do not negatively affect the shape of the eaves edges, and the entire load is redistributed to the transverse beams.

The above methods of hemming overhangs are suitable for cornices. As for the pediments, it is permissible to use only one of the methods, the features of which are described below. This is due to the unusual shape of the gable overhangs and the characteristics of the load that falls on them. If the cornices are practically not exposed to crosswinds, then the gables, depending on the angle of their inclination, can suffer significantly from this.

Taking into account all the features, a method of hemming along the sheathing for gables was developed.

Along the sheathing

An interesting feature of sheathing a gable overhang using sheathing is that the method remains the same regardless of how exactly the eaves overhangs were hemmed. The timber is directly attached to the sheathing, forming a frame for subsequent sheathing. Subsequently, the sheathing boards are attached directly to these beams running along the entire gable.

The specific design of the pediment has a great influence on the technology of hemming. He it can be located almost flush with the wall (when there are practically no overhangs) or it can protrude strongly. In the first case, the filing is also done to prevent water from getting under it, because the probability of such an outcome is much higher here. In the second case, the entire filing is done from below, and the drainage gutter is fixed there.

It is worth keeping in mind that in some cases it is still worth leaving the cornice or pediment unlined. Of course, this does not apply to cases where the overhang is practically absent or shortened.

In rare cases, the cornice is hemmed and the pediment is left without hemming, and vice versa, but this is rather an exception, since such a combination not only often looks unpresentable, but is also not the most convenient to use. Most often you can find cases where the hemming of both the cornice and the pediment is made in the same way or they are both left without it.

Thus, each of the hemming methods can be used when hemming overhangs with your own hands. This will not cause any difficulties, especially if the person starting the construction has relevant experience.

What to hem with?

A greater influence on the overall appearance of the building is exerted not only by how exactly the roof overhangs are made, but also by the material chosen for this. For hems, you can use various raw materials, ranging from well-known wood to soffits specially designed for these purposes.

There are several criteria that you need to rely on when choosing:

The aesthetic component has an important influence. The material must be consistent with the overall appearance of the building and the surrounding landscape. For example, lining the overhangs of a pitched roof of a high-tech house with carved wooden panels is at least strange.
Another decisive factor is the service life of the material. Remember that overhangs and sheathing in particular have a much greater negative impact than the roof as a whole, so the material must be strong and durable. It is considered ideal to choose an option that has a service life approximately equal to the service life of the roof itself.
Ease of installation also means a lot. Many people decide to hem the overhangs alone, so the material should not be too heavy, fragile or otherwise complicate further work.

Among the variety of materials used for lining overhangs, only a few have all of the above qualities. Some of them are more traditional and have been known since Soviet times, while others have appeared quite recently.

Nevertheless, each of these options deserves attention, since it is these that professional builders recommend taking note of.

Board

Natural wood to this day remains the leader among materials chosen for filing. This is due to the well-known technology of working with wood, relative cheapness and no need to purchase additional tools. You can cut the board, giving it the desired look and shape, with an ordinary hacksaw, and use self-tapping screws to secure it.

Another advantage is that wood “breathes,” creating the most favorable microclimate under the roof. Properly arranged ventilation holes, coupled with this feature, give an excellent result: the under-roof space does not become damp, does not rot, and excess moisture does not accumulate there. As a result, all layers of the roofing “pie” last a long time and perform their functions optimally.

When installing a board, there are several factors to consider.

However, not only the board is a “representative” of wood. This also includes two more varieties that are widely used in hemming works: lining and plywood.

Lining

In many ways, the qualities of lining are similar to boards, but there is one important difference. The lining strips are distinguished by the fact that they are very well processed. Also, as a rule, these are narrow boards, while planed boards can be any width.

When purchasing lining, there are some nuances that professionals especially pay attention to. So, not just any raw material is suitable for filing overhangs. The lining should not be too thick, but extremely thin is a bad solution. It is optimal if the thickness is 2-5 mm. Humidity also plays a role. Extremely dry, overdried boards will quickly crack, and too wet boards will swell.

For filing, it is customary to choose a moisture-resistant lining specially designed for this purpose, which is treated with a composition that prevents the retention of moisture on it.

You can make a similar coating yourself using ordinary wood varnish. You can take the planks out into the open air only after they have completely dried, otherwise there is a high risk that the varnish will dry unevenly and, as a result, swell. Before installation, it is necessary to keep the lining outdoors for about a month so that the material adapts to environmental conditions and does not warp over time.

Lining is the best choice if you don’t want to bother with processing, as is the case with boards. It is worth keeping in mind that lining is somewhat more expensive than planed or edged boards. Its price is about 6 dollars per square meter versus 2.5 dollars (the price of a square meter of board).

Plywood

As with the previous two options, when choosing plywood you need to pay special attention to moisture resistance. Unfortunately, you won’t be able to impart this quality to plywood sheets yourself. You must initially buy plywood with moisture-repellent properties.

The slabs of moisture-resistant plywood themselves are rigid and practically resistant to deformation, so they can be installed in one piece. The slabs are attached to a specially constructed frame made of beams.

Ventilation must be provided in advance, since it cannot be made from plywood. It is imperative to purchase special ventilation grilles.

For many, the appearance of such a filing raises big questions. Without painting or other treatment, plywood boards do not look very attractive, so not everyone decides to make such hemmings. However, everything is redeemed by the durability and strength of the structure. In addition, plywood is lightweight compared to lining and boards, which also speaks in its favor.

Thus, there are plenty of wooden products to choose from. Many are captivated by their environmental friendliness, others by their appearance, and still others by their affordable cost. A number of qualities are unique to wood, while others can also be found in alternative materials such as plastic or metal. In any case, you shouldn’t get hung up on one thing. Before making a final choice in favor of one option or another, it is recommended that you familiarize yourself in detail with all available materials. Only after this can you make a decision that will be informed and balanced.

PVC siding

PVC siding was not originally intended for lining overhangs, but some enterprising craftsmen have adapted it for this purpose. In order to make siding hems, you will need a whole set of parts:

U-shaped strips for finishing edges;
“corners” for finishing joints;
ventilation grates.

First of all, it is worth considering that professionals do not recommend using siding when finishing gable overhangs, since its rigidity will not be sufficient to withstand all impacts. Thus, PVC siding is suitable mainly for finishing eaves.

The number of fasteners per bar plays an important role. There can be a minimum of two, but often the number reaches four. This is due to the width of the overhang: the larger it is, the more often fastenings are installed.

Many people prefer PVC siding because of the large selection of colors, as well as the affordable price, which averages $4 per square meter.

A serious drawback is instability to ultraviolet radiation: already three years after the start of operation, the siding loses a significant share of its saturation. It burns unevenly. First of all, those parts that are located directly in open areas suffer, while parts located in the shade can completely retain their original color. Because of this, over time, the hem can become spotty and unattractive. However, such metamorphoses do not affect the service life itself.

Profiled sheet

Sheathing with corrugated sheets is easy. This is mainly due to the fact that the material is easy to cut and you can easily “cut out” any “flap” from it for hemming.

Profiled sheet is a corrugated steel sheet, processed in a special way so that corrosion does not appear on it. The material is highly reliable, durable, durable, and also has some other advantages, including a huge selection of colors. You can choose corrugated sheets in almost any color. The most popular colors are dark brown, white, and dark green. This choice of colors allows you to create a lining that perfectly matches the roof or walls.

When working with corrugated sheets, you do not need any special tools.

Those that are available at each home or can be easily borrowed from a friend or neighbor will suffice. You need to cut the profiled sheet with a circular saw for metal, and fasten it with ordinary self-tapping screws, having previously drilled holes with a drill.

An interesting find was the “corners” made of corrugated sheets, which make it possible to best close unnecessary cracks and gaps. However, the necessary space still remains due to the relief of the material.

Corrugated sheeting is considered the best material when a beginner has to carry out the work of filing overhangs. It is the one that is least labor-intensive to install and causes the least difficulties. In addition, the price of this material is also affordable, which cannot but please everyone who wants to save money.

Soffits

Soffits most closely resemble siding, but there is one significant difference. If PVC siding was developed for cladding walls, then soffits are a material specifically designed for lining overhangs. Soffits have many modifications designed to make this material ideal for hems:

The presence of special ventilation holes. Some soffit strips are perforated, so there are no difficulties with air access under the roof.
Additional protective coating. It prevents ultraviolet radiation from affecting the spotlights, so they do not fade even after prolonged exposure to open sunlight.
Wide variety of materials. Soffits are made from both metals (copper, aluminum, steel) and vinyl. The plastic version is the most common. This is mainly due to its cost.
Ease of installation. Soffits are supplied in kits that contain fasteners, solid and perforated strips, and connectors. Thus, the hemming process is extremely simplified, and the result is a beautiful and neat overhang. Specialized equipment is also not needed. All tools available in the house will do.

Despite the abundance of advantages, the material has one significant drawback. Soffits cannot be used to cover gable roof overhangs. They are only suitable for curtain rods. It is this small feature that makes many abandon them in favor of other, more traditional options.

Dimensions according to standards

The dimensions of the overhangs are quite clearly specified in GOST. According to these standards, as well as SNiP, the optimal overhang size is 40-60 cm, but practice shows that sometimes these rules have to be neglected.

We are talking primarily about buildings belonging to certain architectural styles. For example, for an Alpine chalet it is appropriate to place the overhang at a distance of one and a half to three meters, and for a modern high-tech house it is appropriate to abandon any overhang at all.

As for materials, there are no mandatory requirements, however there are recommended sizes, the ease of use of which has been confirmed in practice. When choosing planed boards, look for samples that are at least 20mm thick. These are the ones that are best suited for hemming, as they do not sag, do not suffer from the wind, and do not warp.

The length can be any, but it is best if it is equal to the length of the overhang itself (or its width when fastened transversely). This will avoid many joints, and the filing will be correspondingly stronger.

There are no standard sizes even for soffits, although they are specially produced for filing overhangs. However, each of the major manufacturers considers it their duty to offer different sizes than those offered by its competitor, so buyers have the opportunity to choose exactly what they need. Thus, the width of the panels ranges from 30 to 80 cm, length - from 3 to 4 m. The most popular are soffits with indicators of 3.6x0.3 m. As for aluminum soffits, their thickness can be from 0.3 to 0.6 mm. Vinyl thickness is from 1 to 1.2 mm.

How to do it?

There are several options for filing. Depending on which option is chosen, the execution technology will vary:

Parallel to the roof. In this case, the sheathing is done immediately under the rafters. Roughly speaking, the material is simply stuffed onto the rafters. This finishing method is suitable when the roof has a slight slope (up to 30 degrees).
With the arrangement of hanging fillies. The bars are nailed to the rafter leg: some close to the wall, others parallel to the ground. It turns out that triangles are formed under the overhangs. Subsequently, they are lined with the selected material. This technology is the most common.
To Wall. Here the block is nailed to the wall at the level of the lower edge of the overhang. Subsequently, the facing material is simply stuffed between the rafter leg, which forms the overhang, and the nailed beam. This method is the simplest, but is not suitable for wooden buildings due to their tendency to warp.

The first stage of sheathing is the construction of such a box, which will later be finished with materials for sheathing. Pay attention to how firmly the bars are installed. If the work is not done well enough, then there is a high risk that the binder may warp or even collapse in the future. It is also important here to take into account the correction for ventilation, leaving special compensation gaps.

Finishing

As mentioned above, the finishing of boxes is carried out using materials traditionally used for this. Since you can intuitively guess exactly how to stuff boards, lining or corrugated sheets, It makes sense to consider finishing using a new material - soffits:

Prepare all necessary materials. Their set does not depend on what raw materials were used to manufacture the spotlights themselves. So, you need to have a J-profile, J-bevel, finishing profile and the soffits themselves. For fastening you will need screws with wide heads.
Measure out the J-profile, saw off the excess. Do the same with the spotlights. The easiest way to cut is with a grinder, but in the absence of one, you can use an ordinary hacksaw.
There are holes in the profiles for their fastening. Use self-tapping screws to secure the profiles in place. It is necessary to leave a compensation gap of 1 mm between the profile and the heads of the screws.
Trim the soffit strips so that they are 6 mm narrower than the distance between the grooves of the profiles. When installing in winter, it is necessary to make them narrower by 10 mm.
Insert the soffits into the grooves of the J-profiles and secure them. Gaps must be maintained (both between the screw head and the soffit, and 6 or 10 mm).

At this point all work is completed. All that remains is to secure the “corner” along the lower outer edge for aesthetic reasons, but this step is optional.

Professional builders give some recommendations on how to hem overhangs as quickly, easily and with good results as possible:

Be sure to coordinate the material with which you cover the overhangs with the surrounding environment. Pay attention not only to the price of the raw material and the ease of working with it, but also to its relevance.
If you are not sure that you will carry out the installation correctly, contact a friend who is more experienced in these matters or a specialized company. Of course, nothing very bad will happen if you do not sew the roof overhangs correctly, but you will lose time and money.
It is better to carry out work during the warm period - from April to October. Then the materials will not compress so much and you will not have to make adjustments for compression. The same applies to extreme heat: during this period it is better to refrain from construction work.
Be sure to decide in advance exactly where the gutters will be located. Do not vent near this area, otherwise moisture may penetrate the ventilation gaps and cause damage to the roofing layers. The optimal solution would be to arrange internal drainage. Although it is more difficult to implement, such drainage is much simpler during operation.

Hemming the overhangs is not a necessary step, but desirable. Remember safety precautions when starting work.

The eaves overhang of a roof is a structural element that protrudes beyond the walls of the house. An overhang is necessary to protect the structure and the surrounding area from precipitation.

Our article will discuss the construction of the roof eaves. We will talk about the optimal length of the overhang and the types of eaves overhangs.

General information about arranging cornices

eaves overhang device

The method of arranging roof eaves in wooden houses is very simple - you need to nail or embed special profile brackets-templates along the perimeter of the four facades. At the same time, the courtyard should not be located on the northern facade. Then, boards are attached to the brackets, which should first be treated with resin or antiseptic. As a rule, the first board nailed should be about 3-5 centimeters wider than the others. This is necessary to replace the drip.

You can decorate the boards using decorative through carvings. The easiest way to arrange a cornice is to cover the ends of the beams with planks. If the laid rafters do not protrude beyond the walls, then they are built up. To do this, nail pieces of board to each beam.

Do not forget that creating cornice architectural profiles on brick walls requires a certain outline. Its thickness should not be more than 50 millimeters.

Keeping this point in mind, let's consider the surfaces on which the solution can be applied:

Plank structures;
Finished masonry removals;
The frame is made of metal, covered with mesh.

To make profiles for plaster cornices, profile board templates that have a double frame are used. The second fitting is needed in order to stretch the profile along the ground and then remove it. Next, the clean profile is covered with the already free first frame.

The installation of a cornice overhang and its finishing will require the use of rollers instead of a runner. They make it easier to move a heavy template, while respecting all the nuances. If the cornices are located in the incoming corners, then their profiling is best done using special templates.

Useful: To reach the top of the corner with a profile template board, place it near the wall at an angle of 45 degrees.

Right triangle - will act as a slide for the template. A profile board is usually attached along its bisector. A metal profile base is installed between the boards. In this case, the chamfers should be located on the outside. If you want to decorate various profiles of cornices, it is recommended to use decorative plaster. Its filler is marble and granite chips, quartz sand, mica, crushed glass, etc.

Applying plaster in three layers:

The first layer is a spray. It adheres the base to the plaster coating. To obtain this layer you will need a solution with a liquid consistency. Depending on the material, the thickness is also selected - from 5 to 9 millimeters.
The second layer is soil. Its production is carried out from a solution of a predetermined consistency by spraying. The latter must, as they say, “grab.” The thickness of the layers is from 5 to 12 millimeters.
The third layer is the front layer. Its application is carried out overlay, and the thickness should be less than the stated 2 millimeters.

After applying the plaster, you can begin stucco work. They include profile rods for the installed cornice.

Types of eaves overhangs for roofing

eaves overhang device

Frontal – designed to protect the facade of the building. It is performed using slopes protruding beyond the boundaries of the walls. They are usually installed at an angle;
Lateral - made in the form of overhangs, which are located on the sides of the building.

Note that the location of the cornice also determines its width. Most often, side overhangs extend to a distance of 50-60 centimeters beyond the boundaries of the walls of the structure. Front overhangs are up to 1 meter, and this length can be increased.

To arrange the front overhang of a standard gable roof, you need to extend the ridge board to the previously verified length beyond the boundaries of the facade. Then, using the same principle, release the load-bearing roof crossbars, which are fixed to the rafters.

After this, you should fasten the eaves board to the end sides of the roof ridge and the load-bearing beams. You don’t have to line the lower part of the eaves front overhang with soffit. But to improve the favorable appearance of the house, it is still recommended to do this.

Important: To ensure the reliability of the front eaves overhang, proper selection of materials should be carried out. Keep in mind that the horizontal beam and the rafter structure must be the same in cross-section.

In the process of making a side eaves overhang, the roof beams must be extended beyond the outer plane of the wall. The release distance will depend on the width of the foundation blind area and the height of the building itself. After laying the roofing material, the stage of fastening the ends of the beams follows. In this case, a plank frame is used - acting as a roof eaves. This will hide the edge and original roofing underlayment.

The overhang space that remains open is usually hemmed with a special material. As a rule, a groove located at the bottom of the cornice board is used for this. It is recommended to use vinyl siding as lining materials (for more details: “Fitting a roof with siding - instructions”) or tongue-and-groove boards. All materials should be secured at an angle of 90 degrees.

Ventilation of eaves overhang

eaves overhang ventilation

The main rule is the mandatory installation of ventilation. It doesn't matter what type and size of overhang you choose. Ventilation is very important if you are planning to build an attic space. The totality of all ventilation openings should be from 1/600 to 1/400 of the area of the room. The filing of eaves overhangs must contain gaps. They are needed to circulate fresh air in the interior. A special hole is provided to evaporate air from the room. It is located at the ridge of the roof.

Arrangement of cornice overhang and selection of material

Sheathing eaves overhangs involves using boards of any length and width. However, its thickness must be no less than 17 and no more than 22 millimeters.

If the board is small, then it can be attached at the ends. For massive boards (length 6 meters or more), the fastening should be located at every meter of their length.

The best material for creating an overhang for a hip roof is softwood (pine, spruce, larch). Boards must be made of dry material. After drying, there should be no linear deformation of the boards. It is this that leads to damage to the appearance of the filing, as many gaps appear.
In addition to boards, galvanized steel sheets can be used to cover overhangs. The optimal thickness should be 0.6–0.8 millimeters. In turn, perforated sheet material must have a wavelength greater than 20 millimeters.

Important: When working with such materials, do not forget to have special equipment and skills. After adjustment, each sheet must be covered with a protective layer of paint.

Another material for filing overhangs is sheet aluminum covered with a protective layer of pollination. Its width is calculated from the ratio of the parameters of the eaves overhang. The optimal thickness is 0.6 millimeters.

The length of the sheets should not exceed 6 meters, because latches are used to fasten the sheathing. And if the sheets are longer than the required length, they will sag.

Useful: Manufacturers of decorative products for eaves can provide you with a wide range of their products. As a rule, you can find it in specialized stores.

Covering eaves overhangs on soft roofs

In winter, a large amount of snow forms on the roof eaves. This can lead to the destruction of the overhang, and then the cornice or even the walls.

With a minimal roof overhang on a hip roof, poor-quality eaves can lead to destruction of the masonry and outer surfaces of the walls. In a wooden house, the upper and lower logs of the log house will rot. Once wet and dry, logs can seriously crack and lose their seams and caulking. If you do not carry out high-quality waterproofing, the cladding of the log house, coated with oil paint, will deteriorate (read: “Roof overhangs - classification and installation”).

Eliminates the line connecting the top of the load-bearing wall and the internal structure of the roof slope;
Makes the facade of the house complete. It also provides improved protection for building walls.

Eaves overhang of soft roof

Cornice overhangs

What are eaves overhangs? Overhangs are a structure that protrudes beyond the lines of the load-bearing walls of a building to a specific length. The main role of overhangs is to protect supporting structures from the effects of snow, rain and melt water that flows down the roof.

Cornices: classification and main types

There is the following classification of overhangs:

Hemmed. In most cases, they are used on hip and gable roofs.
Unfiled. This type of overhang is considered the most common; it is used in almost every roofing structure, both single-pitch and gable.
Shortened. They are used on each of the main roof structures.
Box-shaped. They are used for hip single-pitch and gable roofs.

Eaves overhang assembly The house is selected depending on the climate in the region in which construction is taking place. The structure of the roof eaves is quite diverse and is divided into the following main categories:

Flush eaves overhang. In this case, the rafters do not extend beyond the boundaries of the walls, and along their edges a horizontal drain board is fastened, to which gutters are subsequently mounted. The disadvantages of these overhangs include the lack of protection of the upper elements of the wall from moisture.
Open overhang is widely used in private construction. The drainage system is fastened to the upper edges of the rafters or along their lower edge.
Closed overhang. For such an overhang, the protruding ends of the rafters are covered with the help of a cornice, which has a special groove for fastening the soffit on the inside. If there is an insulated attic, such a cornice must have a ventilation hole.
Gable overhang. In this case, the roof structure is completely determined by the designer’s imagination and can protrude beyond the boundaries of the walls and be arranged flush. The protruding area of the roof requires mandatory hemming, the width of which is at least 50 cm.

Pediment and cornice overhangs in the photo will allow us to consider them in more detail.

Materials used for covering overhangs

The most popular materials used for covering roof overhangs include wood and metal.

Boards. In most cases, this material is obtained from coniferous trees; it has moderate wood moisture content. The thickness of such cladding, according to GOST, is 17-22 mm, and the width and length are selected individually for each specific case. Fastening is carried out on both sides in increments of up to 1 m, having previously been treated with impregnation from a moisture-resistant composition. As an impregnation, you can use a special protective varnish or moisture-resistant paint. Wooden roof overhangs require constant maintenance. Treatment should be carried out every 3-5 years. In this case, the overhangs will last longer and retain their original appearance. In addition to the protective coating, the structure must be subject to ventilation. To do this, inlet openings should be arranged at a rate of 1:400 of the ventilated weight area. With proper organization of ventilation, air exchange will be carried out through drilled holes and holes in the roof ridge. Protective nets are used to protect against birds and insects.
Cink Steel. This type of roof overhang lining takes the form of a steel sheet, the thickness of which is up to 0.8 mm - flat or perforated. Anti-corrosion paint is applied to the edges of the sheets.
Aluminum sheets. They are coated with a protective layer, which prevents the formation of metal corrosion. The dimensions of the sheets can be within the following limits: thickness – 6 mm, width – 100-300 mm, length – 6000 mm. Aluminum cladding sheets should be fastened using specially designed latches.

Eaves overhang size

The width of the roof overhang is determined taking into account its location. The minimum value of the overhang width according to SNiP can be 40 cm, and in the case of unorganized drainage - at least 60 cm. For side overhangs, in practice, the extension of structures beyond the boundaries of the building reaches a value of 50-60 cm, for front overhangs this value can reach up to 1 m.

The length of overhangs in a wooden house is used from 550 mm, in brick and panel houses - up to 550 mm. But there is also a minimum roof overhang - its length can be 400 mm, and in some cases size the eaves overhang reaches even 1200 mm.

Options for filing cornices

Eaves overhang trim can be carried out in the following ways:

Lining eaves overhangs with siding.
Lining eaves overhangs with wood is considered one of the best options for finishing eaves. Pros: naturalness and beauty, which cannot be achieved when using non-natural materials. It is for these reasons that this type of cornice finishing is becoming increasingly popular. In addition, wood is a living, organic and environmentally friendly material for sophisticated finishing.
Lining cornice overhangs with copper is considered the most sophisticated type of finishing for cornices. Pros: beauty, durability and naturalness, making this type of cornice lining unattainable by other analogues.

Features of design and installation of eaves overhangs

When designing and installing a cornice overhang, the following should be taken into account:

The amount of overhang of the eaves overhang from the load-bearing wall. It represents a design value that depends on the load-bearing capacity of the structures and other factors taken into account when developing the project.
Eaves overhang of soft roof must provide ventilation in the under-roof space.
Methods and fastening elements for decorative panels (copper, wood and other metal cassettes, etc.) must ensure reliable fastening of the panel under all weather conditions.

With proper installation of roof overhangs, the appearance of the walls of the house and the roof itself will preserve its original appearance and its operating properties for a long time.

Eaves overhangs, How to build a house, make repairs

Eaves overhang for soft roofs Eaves overhangs What are eaves overhangs? Overhangs are a structure that protrudes beyond the lines of the load-bearing walls of a building to a specific length. Main

Installation of a pitched roof cornice assembly

Any roof of the house is accompanied by the installation of a cornice. Even a flat roof, which is made using rolled materials, is equipped with a cornice. Its installation is necessary to prevent water from entering the under-roof space during rain. An exception may be roofs that are equipped with a parapet.

The cornice is installed in order to prevent moisture from entering the under-roof space.

In addition to its functional obligations, the cornice acts as the final finishing of the roofing structure, since after the completion of the filing, the internal components of the rafter system are closed. To ensure more effective protection of the rafters, the base of the roof of the house is extended beyond the walls by a length of 50 cm. In some cases, this figure may be slightly increased.

Properties of roof overhangs

Internal structure of the roof eaves. To make the box, you should select untwisted, even boards without bark and knots in large quantities.

In some cases, the design of the rafter system is not equipped with projections extending beyond the walls of the house. In this case, a method is used that involves forced lengthening of the rafters due to special elements, which are called fillies.

It is worth noting that we must not forget about the protection of the building’s pediment, which is provided by the installation of a cornice. The width of the overhangs that protect the gable of the house should not be less than 500 mm. In this case, a cornice type board is installed on the edge of the roof. The lower part of the cornice structure requires obligatory covering. Cornice nodes are most often sheathed with boards.

It is important to remember that the design of the pitched and frontal cornices is strikingly different from each other.

Types of eaves overhangs

Diagram of the eaves overhang arrangement: 1 - rafters, 2 - eaves overhang boards, 3 (4) - support board for soffits, 5 - soffit, 6 (7.8) - sheathing, 9 - gutter, 10 - drip edge, 11 - eaves bar (apron).

Throughout the history of house construction, a huge number of varieties of overhangs have been invented, which have been successfully applied in practice. The main types include:

Unlined overhangs - used when installing a hip roof on a house for both pitched and gable structures.
Hemmed overhangs are also most often used on hip roofs and are widely in demand when installing gable roofs.
Box-shaped eaves overhangs are used in the construction of pitched and sloping roofs.
Shortened roof eaves are used on absolutely every type of structure.

A Danish roof will also look good with such eaves.

Types of eaves overhangs

The roof eaves assembly of a house is selected depending on the climate in the region in which construction is taking place.

Knots of eaves overhangs can have several types. Therefore, it is very important to dwell in more detail on the features of their design.

Installation diagram of a cornice overhang in the presence of a frontal board.

A flush eaves overhang is installed in cases where the rafter system does not extend beyond the front boundary of the wall. This requires strengthening the edge of the rafters using a drain board, which is located in a horizontal position. This is done in order to protect the gable of the house from moisture penetration. This also ensures that the gutter system is secured. In addition, such design features give the broken roof originality.

Despite the advantages, this unit has one drawback, which is that the upper part of the wall is not protected from water. The overhang unit, made flush, has a length that is at least 50 cm. If it is installed in buildings made of bricks or panels, you can make a protrusion with a shorter length.

Installation diagram of a cornice overhang without a front board.

If, during the construction of the gable of the house wall, the puffs are allowed to extend beyond its line, it is recommended to install cornices that will help prevent the formation of drafts in the attic and prevent snow from blowing into the cracks of the wall structure.

The absence of protrusions of the rafter legs of a sloping roof beyond the line of the walls is replaced by the extension of the fillies, for which trimmings of timber are used. They are screwed or nailed to the rafter ends. After this, the cornice board is attached to the scraps.

Knots of open-type eaves overhangs are formed when the main rafters of a gable roof protrude beyond the gable of the building. In this case, the drainage system is connected to the side of the rafters or to its upper edges. The design features of this unit allow it to be used in the construction of sloping roofs in private homes.

Closed-type cornice units are formed when rafters protruding beyond the gable part are closed with an overhang. For this purpose, a special groove is used on the inside into which the sheathing elements are inserted.

The pediment assembly can be arranged not only flush, but also protruding beyond the walls. The choice of method depends only on the wishes of the owner of the house and the designer’s ideas; in any case, it will be correct. Regardless of which method is chosen, the part of the pitched roof that is not protected in any way must be sheathed.

List of materials and tools for sheathing overhangs

Selection of materials

Most often, the eaves of a gable roof are sheathed with boards made from coniferous wood, since this material is considered the most preferable. When choosing a material, you need to pay attention to its moisture content. Material that is too wet can become deformed over time, which will ruin the appearance of the overhang.

Installation diagram of a cornice overhang with a width of more than 45 cm.

It is worth paying attention to the thickness of the wooden cladding, which should be at least 17 mm and no more than 22 mm. And the width and length of the board is selected individually. The sheathing is mated on both sides. This does not apply to boards with a length of more than 6 m. In this case, mating is performed in increments equal to one meter of the length of the material used for cladding.

The boards used to cover the eaves of a gable roof must be treated with a waterproof compound. This is done before starting work. For this, special paint or varnish designed for wood processing is used. Wood siding must be treated every 2-3 years. Only in this case will it be able to serve for a long time. In addition to boards, other building materials can be used for cladding:

Scheme of filing the eaves overhang.

Galvanized steel sheets. When covering roof eaves, steel is used, the thickness of which should not exceed 0.8 mm. In addition to ordinary steel, metal sheets with perforations can be used. To cut such material, special equipment is used. After the sheets are ready, they are coated with paint to prevent corrosion.
Aluminum sheets. Their thickness should not exceed 6 mm, and their width should not exceed 30 cm. Special latches are used to pair the sheets.

To cover overhangs you will need a standard set of tools used in roofing:

building level or plumb line;
hammer;
roulette;
screwdriver;
fasteners;
pencil;
construction corner ruler.

Ventilation system design

An example of covering an eaves overhang with siding is one of the most popular materials, along with wood.

Each curtain rod assembly must be provided with high-quality ventilation. It is satisfied regardless of what design features a particular cornice unit has. The exhaust openings should have a diameter that is equal to 1/400 of the area to be ventilated. If all calculations are performed correctly, including the mating of the cornice parts, then air will penetrate into these holes and exit through the cracks located in the roof ridge.

A ventilation device for the space located under the roof helps to avoid damage to the supporting truss structure. In addition, high-quality ventilation will provide the attic with an excellent internal microclimate.

Ways to strengthen the cornice

If the unit is installed incorrectly and the mating of its skin is not carried out according to the rules, the cornice will begin to deform and sag under the influence of wind and snow load. To avoid such troubles, it is necessary to ensure that the overhang sheathing is properly paired with the roof truss system.

To ensure more effective protection of the cornice, it is necessary to secure the connecting elements of the rafter system as carefully as possible.

To prevent clogging of the drainage system, a heating system must be installed in the area of the roof that is located in front of the overhang. This will ensure instant melting of the snow, which will subsequently be drained into the drain. Due to this, the load on the roof eaves will be significantly reduced.

Pitched roof eaves assembly: installation methods

You can install the pitched roof eaves assembly yourself. This element is necessary to protect the roof from precipitation.

Roof overhangs: types and features of sheathing

Overhangs are roofing elements designed to protect the external walls of a building from the effects of precipitation.

They are a structure that protrudes beyond the walls of the building.

Our article will tell you about the features of the design and installation of overhangs, their varieties, methods of cladding and providing ventilation.

Varieties

There are two main types of eaves overhangs:

If we take a gable roof as an example, then there will be side overhangs along the side walls of the building, and the facade will be protected by a front (gable) overhang.

Frontal can be either protruding or flush.

This moment depends on the design idea.

When installing a protruding overhang, the roof ridge is extended by a predetermined distance (up to 1 m) beyond the building facade.

The load-bearing roof crossbars attached to the rafters are also lengthened.

Then the cornice board is installed - it is fixed on the end sides of the ridge and the supporting beams of the sheathing.

Often the lower part of the front overhang is hemmed to give the roof a more aesthetic and complete look.

Side overhang can also be provided for by the dimensions of the elements of the rafter system during the construction process.

Otherwise, the installation of fillets is carried out - bars, which are a continuation of the rafters.

The fillies are attached to the ends of the rafter beams, and the cornice board is mounted on them.

The exact value is determined taking into account the height of the building, the width of the foundation blind area and the material from which the building is constructed (wooden, brick, panel buildings).

Photos

Varieties of execution from various materials are shown in the photo below.

Roof cornices made of corrugated sheets

Finishing materials

The most common cladding option is softwood boards.

The material must be dry, since wet wood will dry out over time and become deformed, which will worsen the appearance of the roof.

Boards intended for cladding are treated with an antiseptic compound, varnished or painted.

The fastening of the sheathing elements is carried out in increments of 1 m.

It is enough to fix boards less than 6 m long in two places - at the edges.

This design requires restoration every few years.

Galvanized steel sheets are also suitable for sheathing roof eaves.

The thickness of the steel should be in the range of 0.6-0.8 mm.

Installation of steel sheets must be carried out using special equipment; first, marking and cutting of the material is carried out.

All edges are treated with paint to protect against corrosion.

Aluminum sheets coated with a protective layer by spraying are also suitable for finishing roof overhangs.

It is better to choose a thickness of 0.6 mm, and a length of no more than 6 m.

Aluminum plates are fixed using special latches, so skin elements that are too long will sag.

Installation methods

According to the rafter structure

The lower plane of the rafter structures is leveled by installing overhead boards according to the markings.

First, the outer parts of the structure are mounted, then the final installation is made using a fishing line or rope stretched between them.

According to the prepared frame

In this option, the rafters are first cut in the vertical and horizontal planes.

A beam is fixed on the horizontal cut; the same beam is attached to the wall 10 cm higher than the front board (to ensure natural removal of moisture).

Installation of the front overhang

The frontal board of the front overhang is fixed on the sheathing parallel to the pediment of the building.

See about lining the roof gables. What and how to hem the pediment.

For information on installing a valley when roofing with corrugated sheets, follow the link. Also about the construction of a valley on a soft roof.

Find out how cheaper it is to roof a house here. How to cover the roof of a private house.

Ventilation and protection

Ventilation of overhangs is necessary to ensure a favorable microclimate in the attic, as well as to protect the elements of the rafter system and sheathing from damage.

Ventilation can be provided in two ways:

leave a gap between the wall and the sheathing material;
install special plastic grilles into the sheathing elements.

The air flow entering through the ventilation holes is discharged through the holes in the roof ridge, provided in advance.

All openings in the roof overhang must be protected with mesh to prevent birds, insects, and rodents from entering the attic through them.

If the attic space has a large area or you plan to install an attic, you need to take care of a more substantial ventilation system.

If the roof is insulated, the thermal insulation material must have ventilation holes.

To protect against deformation under the influence of strong winds or heavy rainfall, you need to check the quality of its installation.

Both the overhang and the sheathing material must be integrated with the roof rafter system.

Monitor the reliable fixation of the elements, as well as the condition of the drainage system - its clogging will lead to sediment retention on the eaves and great pressure on the overhang structure.

Proceed with the installation and finishing of the roof overhang only after carefully studying the theoretical part of this issue.

A high-quality overhang will provide reliable protection for the facade and extend the service life of the roof and the building as a whole.

Roof overhangs: design, dimensions and minimum overhang

Installation of roof overhangs is carried out to protect external walls. Let's consider what types of overhangs exist, how they are installed and filed, why

The roof overhang is not the most important part of the roof, but it can be used for a wide range of different tasks. Provided that the calculation is made correctly, the cornice will advantageously emphasize the levels and planes of the slopes, as well as perform a number of useful functions. In modern houses, much attention is paid to such elements even at the design stage. How to make a roof eaves so that it is as practical and aesthetically attractive as possible? To do this, you first need to determine its configuration, then the parameters and possibilities for decoration.

What tasks does the cornice perform?

The proportions of the cornice can change the visual image of the house, increasing or decreasing its expressiveness. One should not discard the stylistic accents characteristic of a particular region. Architectural traditions are being revived today in the private residential sector, where owners seek to emphasize the special style of a particular area. As for the tools for achieving a particular image, both the size and shape of the eaves overhang will be important. The photo of the roof presented above, for example, demonstrates the advantages of a massive overhang in relation to a small house. Visually, the structure becomes lower and wider, which adds a sense of reliability and good quality to the perception of the structure.

Functional objectives will mainly be expressed through design capabilities. In part of the cornice, you can lay communications, arrange outlets for ventilation and chimney, and install other engineering and technological channels. The width of the overhang will also affect the microclimatic properties of the house. The fact is that the long overhang of the cornice shades the window, absorbing thermal energy. If we are talking about a metal roof, then accumulation will occur very quickly, passively warming up the entire roof covering. This effect can be used differently in winter and summer.

Installation of roof eaves

An overhang as such is a structural unit in which the slope and horizontal ceiling meet. The latter can only be a cornice strip extending from the point of attachment of the Mauerlat to the outer wall. The configurations for connecting parts of the rafter system may differ, so there cannot be a single principle for determining the elements of a given unit. One way or another, in any design an important role will be played by the roofing pie, forming an overhang. This is the part of the slope that extends horizontally to the side beyond the level of the outer wall, and in some cases it can drop significantly below the level of the attic floor horizontally.

Now it’s worth moving on to the materials. The roof structure is determined by the combination of the load-bearing base of the slope with wooden (or thin metal) beams, sheathing and outer covering. The outer layer can be represented by a soft roof, corrugated sheeting, tiles, etc. In essence, this combination will provide an external protective frame for the eaves. The cornice itself is formed by the bottom strip, which connects the outer wall and the slope. It is also often made of wood, but plastic is also found.

Types of eaves overhang

There are several options for roofing eaves, which differ in design and functionality. The most common is the usual closed cornice, which has a slope of average slope and reach and a horizontal strip that forms the soffit. A simpler design dispenses with the bar altogether. The overhang is also directed along an inclined slope, but there are no covers on the bottom side - the result is an open structure, which has significant pros and cons. Firstly, this is a standard eaves overhang with metal flooring. The covering is quite flimsy and of little functionality, so with such a slope there is no point in installing closed eaves boxes. Secondly, this solution requires a higher degree of insulation at the point of convergence of the Mauerlat and the roof.

Brick structures represent a special group of eaves overhangs. Instead of a wooden plank, the lower part of the overhang in this case will be covered with brick (or masonry). This option is used infrequently, but with its help you can create original facade designs.

Features of eaves on soft roofs

This type of roofing is one of the most problematic in the sense that the material is heavy and puts a significant load on the slope. Accordingly, you should focus on strengthening the structure from below and from the sides. The optimal design of an eaves overhang for a soft roof may include a sheathing using wooden bars and metal fasteners. The strength base will be provided by anchor connections along the entire length of the sheathing fastening, as well as metal corners and mounting plates, which will act as additional fasteners.

Features of flat roof eaves

In this case, the design is simplified, since there is no need to create an inclined angle of the slope with the corresponding designs from the bottom. That is, there will be support and sheathing from below, but it is much easier to implement it horizontally. In its simplest design, the eaves overhang of a flat roof can be designed as a combination of a straight slope and a ceiling. Roughly speaking, the attic floor will extend to the side beyond the boundaries of the outer wall. At the top level there will also be a roofing pie on the slope. Next, all that remains is to close both structures on the side with plastic or wooden sheathing. The result is a fairly functional box of the correct shape.

Roof eaves parameters

As before, in our time, the optimal way to calculate the width of the cornice is the overhang angle. It may vary depending on the slope of the slope. On average, Russian houses are designed with roofs whose slope varies from 30 to 45 degrees. What offset will be optimal? There is a special regulation that determines the range of sizes of the roof eaves in width from 10 to 70 cm. Further, everything will depend on the type of roofing material. Thus, the shortest eaves are used on roofs made of rolled metal - from 10 cm. Galvanized steel sheets allow you to install overhangs with a minimum length of 15 cm. And corrugated asbestos concrete panels are made with a width of 25 cm.

Installation of cornice

Installation of this element mostly comes down to back cladding with wooden planks, plastic panels or siding. The main thing is not to use metal in this part, since the removal of condensate through the soffits creates favorable conditions for corrosion. How to install a roof eaves? When the contours of the slope and mauerlat have been determined and their structures are ready, you can begin installing the load-bearing sheathing for the filing. It is advisable to use small-format timber. The supporting parts are fixed with screws to the wall or mauerlat - as the design allows. A series of small planks with indentations of approximately 20-30 cm are attached along the lines of the supporting planks. At the final stage, sheathing is done across the entire area on the back side of the cornice - plastic or wooden lining.

Cornice ventilation system

Even at the stage of developing the cornice scheme, it will not be superfluous to determine the method of implementing the ventilation system. Air circulation in the under-roof space is necessary to combat dampness, which is harmful to the wooden rafter system. The simplest way to install ventilation in the eaves of a roof is to initially use perforated plastic panels for cladding. They are specially designed as soffits under the cornice for organizing the air duct. If wooden planks are used, then you must first leave space for gaps. Sometimes, for such purposes, they simply maintain a space of a few millimeters between the sheathing strips. Actually, it is enough that the eaves box is not completely sealed.

Conclusion

The cornice is a significant and important part of the roof, but very delicate in execution. Much in the implementation of this element will depend on neighboring materials of construction. For example, the eaves overhang of a soft roof cannot be installed without taking into account the characteristics of the coating, which often limit craftsmen in the choice of technical solutions. For such a roof, it is better to turn to special additional soffits that will cope with the loads from a heavy roof and provide the necessary space for possible installation of communications in the box.

If the slope is covered with light corrugated sheeting, then you can completely do without capital support with the formation of the skin. It is enough to take care of the mechanical protection of the unit and ensure free air circulation in the joint areas. But, on the other hand, the absence of a mounting box in itself excludes a whole range of design possibilities, also related to the installation of drainage elements and snow retainers. For this reason, counting on the long-term operation of the roof, it is worth considering the role of the eaves from the point of view of a variety of aspects of application.