Sheathing of roof overhangs: sheathing options and execution technique

The protection of the roof of the house and its attractive appearance are issues that require careful consideration. One of the possible solutions is a neat finish of the overhangs, which will reliably protect the truss elements from atmospheric influences and ensure the aesthetics of the roof.

The cornice overhang of the roof of a house is usually called its lower part, protruding beyond the boundaries of the walls. It is designed to protect the walls and the blind area of ​​the foundation from getting wet during rain.

Hemming of roof overhangs according to the requirements of SNiP is not considered a mandatory operation. Nevertheless, many experts recommend not neglecting the filing of roof eaves. It will solve a number of important issues, for example,

• in strong winds, ascending air currents arise, which, having penetrated under the overhang, tend to tear off the roof, and the filing of the roof overhang will become an obstacle in their path and will not allow oblique streams of rain to enter the under-roof space;
• filing the roof overhang will hide the truss elements, the release of the layers of the roofing pie and the roofing from the side of the attic, and more.

Finishing the roof eaves is the final stage in its construction, therefore, hemming the roof overhangs is performed after

• her devices;
• insulation and finishing of external walls;
• drainage installations.

Types of overhangs

• Eaves or side. These are horizontal overhangs that are formed by the lower part of the slope. Ventilation of the space under the roof also passes through them. After passing through the overhang, the air moves towards the ridge, drying the layers of the roofing cake along the way. Hence the conclusion that it is impossible to close them completely. But after all, it is also extremely undesirable not to sheathe the structure. So, you need to find a reasonable option, how to hem the roof overhangs, so as not to block the access of air under the roof, but for birds, insects or rodents - yes.
• Fronton. They are formed by the sloping edges of the roof slopes and do not take part in under-roof ventilation. Therefore, the need to finish the roof eaves for gable overhangs is due to other reasons, namely the inclined plane of the structure. It is highly susceptible to the destructive effects of moisture, which is blown by the wind. This is especially dangerous for a mansard roof, since the edges of the insulation are not protected from getting wet. Gable cornices must be completely sheathed. Thus, the filing of the gable overhangs of the roof will become impenetrable.

How to finish the edges of the overhang

Both on the gable and eaves overhangs there are unclosed elements: the ends of the rafter elements and the end part of the lathing outlet, respectively, which must be finished before the roof eaves are hemmed.

The choice of material for finishing the edge of the cornice or its end part depends on the main material of the roof covering. Quite often, manufacturers supply ready-made edge finishing kits along with the roofing material. The sheathing process itself is performed according to one of the following algorithms.

• All protruding truss elements or fillies are cut in one straight line strictly parallel to the wall, that is, vertically. Then the ends of the rafter legs are connected with a strapping board. A frontal roofing board is attached to it, the dimensions of which should allow the ends to be covered: completely or partially with a minimum shortage. It is on it that the gutters of the drain will be installed in the future.

The frontal board is made of metal or wood. For roofs made of tiles of known types, such a board is included in the set of roofing material. The frontal board is attached to the ends of the truss elements using galvanized nails or self-tapping screws.

• The elements of the crate that protrude beyond its limits are cut parallel to the wall at the same level. An end board is nailed to them and tied to the end of the roofing beam. If the board is standardly fixed only to each element of the crate, then it will not be possible to achieve a sufficient degree of rigidity, therefore it is recommended to use a T-shaped connection.

To do this, additional elements are hemmed from boards or bars, placing them between the frontal board and two adjacent purlins, starting from the second, in increments of one interval, that is, every second and third are chosen.

Binder options

In principle, the filing of roof overhangs is performed by any convenient method. But on closer examination, all of them can be combined into two techniques.

One of the options for filing is directly along the truss elements. The main requirement in this case is the location of the open ends of the rafter legs in a single plane.

• This method is suitable for roofs with a slope angle of not more than 30˚, the overhang of which does not exceed 0.4–0.5 m.
• Hemming strips are stuffed onto the base of wooden parts nailed to the rafters.
• You can sheathe the base both along and across.
• Installation begins with the installation and fastening of the initial and last trim strip.
• Then a building thread is pulled between them and, observing a verified level, the rest are put up.
• When hemming the corner of two slopes, the planks must be fixed to the corner rafter on both sides.

Horizontal sheathing of roof overhangs is used on steep slopes. Installation of the roof eaves is quite fast.

• A box is knocked down from wooden beams, which is attached to the adjacent wall and the base of the roof, and the wall beam must be placed 1 cm higher than the beam attached to the lower section of the rafter legs. Thus, they maintain the slope necessary for the flow of water that has fallen into the cornice due to the wind.
• To ensure the rigidity of the box structure, the fastening of the bars with screws is duplicated with additional fasteners on metal plates and corners. Then proceed to filing it with some convenient material.

materials

Various materials from metal, plastic or lumber are suitable for filing the eaves of the roof.

• The most common is the filing of roof overhangs with a board 15-20 mm thick. The width of the material depends on the overhang of the cornice and ranges from 5–25 cm. The aesthetic appearance of the sheathing depends on the exact observance of the constant width of the boards.

The undoubted advantage of a board for filing roof overhangs is its ability to provide high-quality ventilation of the under-roof space, since the air in this case evenly enters there along the entire perimeter of the roof. The gap between the boards is 1–1.5 cm.

• If the boards used for hemming are of sufficient length, they are screwed at several points to prevent deformation.
• The boards are joined, adhering to a checkerboard pattern. In this case, it is necessary to leave a sufficient distance between the two joints.
• The only exception is the corners of hip roofs, where the wooden planks are cut down when joined, dividing the right angle in half.
• All elements are treated twice with antiseptics and fire retardants: before and after installation.

• Another popular material is wood lining. Given the susceptibility of wood to all sorts of vagaries of the weather, special requirements are imposed on its quality:

• strips should not have a small thickness;
• humidity level. The natural humidity of the lining, which was stored in the open air for at least a month, is considered optimal.

The planks of the lining are laid tightly, leaving no gaps between them, as in the case of a board. Ventilation holes are cut out on the finished skin with a step of 150 cm, which are covered with gratings.

• Sheathing of roof eaves with corrugated board coated with polymers is performed according to a simple algorithm.

• When sheathing cornices with a profiled sheet, sheets of the desired size are preliminarily prepared. They are screwed to the finished frame parallel to the wall. For fastening use special screws.
• The joint formed by the plane of the wall and the profiled sheet is closed by installing additional elements: a frontal bar and an inner corner. The corner is attached to the profiled sheet, and the bar, respectively, to the board. To close the external joints of the profiled sheet, use the outer corners.
• The filing of the gables of the roof (photo above) is performed along the walls. Planks are fixed to the outer edge of the cornice and hidden under the end plank and corners. Sheathing strips should be approximately 2 cm narrower than the width of the overhang. Thus, the air intake will occur due to the height of the profile wave.
• When installing the roof cornice, the profiled sheet can be finished in color by choosing the appropriate one from a variety of options.

• PVC siding is a fairly affordable and effective option for filing roof eaves. This material often goes on sale in a special configuration. Plastic panels are supplemented with U-shaped strips, necessary for the design of edges, corners, as well as ventilation grilles. The sheathing is attached parallel to the edge.

Plastic strips are attached to a wooden frame at two to four points.

• For filing the roof cornices, special plastic panels are produced - soffits. These panels are thicker than siding and usually have special perforations through which the roof space is ventilated. In addition, UV stabilizers have been added to the plastic for spotlights, which provide the material with high resistance to ultraviolet radiation. Soffits for filing are cut along the length of the cornice and installed at a right angle to the wall.

See the various options for filing roof eaves on the video