Correctly made lathing for profiled sheeting - guarantee of strength and reliability of the roof
Lathing for profiled sheeting
Lately, most builders and builders have chosen corrugated board as the roofing material. This is a quality material that can protect against the effects of sediments, bacteria and fungi and permanently preserve the building.
Mounting of corrugated board is quite simple, but it is very important to observe all construction norms and technologies. When laying corrugated board the basis of the bases will be the correct installation of beams, rafters and battens.
Wooden or metal beams are laid on the base of the roof. They should protrude about half a meter from the wall. The basis for the roof is the staple system, consisting of:
- Racks of vertical;
- Scaffolding inclined;
- Leg of inclined rafter.
The figure shows the installation scheme of the
crate. The rafters are installed at a distance of 60 to 80 cm from each other, taking into account the total load of the building at a certain angle of inclination. Rafters are made from dry coniferous wood to prevent possible deformation of the structure. The angle of the rafters in places with increased snowfall is 35-45 degrees. In areas with more moderate weather conditions, you can make an angle of 20 degrees.
Special care should be taken when installing the corrugated board. It is a special design, made with regard to the parameters of the roof, which will serve as a framework for corrugated board. As a wire, metal elements and wooden beams are used. Only properly mounted frame will allow the roof to withstand increased wind and snow loads.
Types of roofing roofs
For industrial buildings, metal frames or skins made of metal elements are most often used. Roofing on industrial buildings, as a rule, does not have a large slope, but the spans are quite large, so the sheathing under the corrugated board must be strong and reliable to withstand heavy loads.
When constructing private houses, a wooden crate is used, made of a board or a bar treated with an antiseptic. The most commonly used boards are 25-30x100 mm. The cladding is mounted only after the waterproofing material has been laid. It absorbs moisture from the side of the thermal insulation and prevents the condensate, which is formed on the lower surface of the roofing sheet due to atmospheric fluctuations.
The clipping can be:
- With the usual step. For this purpose, between the boards or bars, a distance of 20 to 40 cm is maintained. This type of sheathing is most often used for profiled sheeting.
- Solid crate. The gap between the boards is 10 mm to avoid damage due to drying or swelling of the boards. Sometimes as a continuous sheathing sheet materials: OSB, plywood or waterproof chipboard. This type of crate is most often used for small-piece materials, for example, tiles or roll bituminous coatings.
- Sparse battens. In this case, the step of the lath makes from 50 to 75 cm, and sometimes even more.
The type of the battens depends on two parameters: which brand is used for corrugated board, and what angle of roof inclination. For example, if the angle of the roof is 15 degrees, then for the C10 corrugated board you have to perform a continuous littering, for corrugated board C21 - the usual lathing with a step of 300 mm, and for corrugated board C 44 - thin roofing in steps of 500 to 1000 mm.
Example of the
crate For maximum roof strength at high loads, a two-layer crate can be installed. In the lower row, you can perform a sparse littering, and in the upper row - a lath with a regular step or a continuous litter. The lower row runs parallel to the roof ridge, and the upper row is perpendicular to it. Two-layer crate is also installed when laying a thick layer of insulation thickness of 100 mm. In this case, across the rafter, two blocks of 50x50 mm are attached in series.
Conventional lath is made of a wooden beam with a size of 50x50mm, 60x60mm or 75x75mm. It is possible to perform the usual lathing from a board with a width of no more than 150 mm, and a thickness of 20 to 50 mm. It is very important that the width of the board does not exceed 15 cm, otherwise the tree is prone to increased deformation from the effect of various temperatures and dampness.
Nails or self-tapping screws are used as the fastening of the crate. In this case, their length should be equal to the double thickness of the crate. For example, if you use a bar 50x50mm, then you need to take fasteners with a length of 100 mm. The cladding is attached to each roof rafter. The beam and boards should not have any defects and protruding knots.
Installing the crate for profiled sheeting
First you need to mark the position of the beams or plank boards on the outer rafters. Then along the entire slope measure the fixing points of the board whether the beam. If a groove or a bulge is found on the fixing point of the beam or board, then it is removed by shaving or piling the rails or roofing material of the required thickness.
The lathing starts from the ridge. The distance between the boards or bars of the sheathing under the corrugated board should be at least 20 cm and not more than 40 cm. The wooden sheathing often has to be spliced along the length, because the standard length of sawn timber is usually less than the length of the ramp. For this, the edges of the spliced pieces are first fastened with nails, and then mounted on the roof so that the joint of the timber falls on the rafters. In different horizontal rows the joints must be displaced. For this, the boards are cut to a certain length.
Windboards are installed at the ends of the roof. Their height should be greater than the crate by an amount equal to the height of the profile of the corrugated board.
Layout of material
Corrugated board is fastened to the crate with the help of screws with zinc coating. As a spacer between them a rubber washer is used. For each square meter of coverage, at least 5 pieces of self-tapping screws are necessary. Between each other, the sheets are joined with rivets.
In order for the roof to last a long time, it is necessary to determine its purpose in advance, carefully perform all necessary calculations and correctly select the roofing material. When using profiled sheeting, it must be remembered that the higher the profile height, the greater the load it can withstand. When building private houses, a corrugated board with a height of 35 mm and a thickness of 0.6-0.7 mm is used. Profiled sheeting with a lower profile height is installed with a smaller step of the trolley to ensure the required rigidity and strength of the roof. If the lath is correctly installed, the roof weight will be distributed evenly, it will be strong and will withstand all the vagaries of the weather.
If chimneys or various parapets pass through the roof, a separate crate is installed under them. For chimneys, it must be located at least 15 cm away.
It is recommended to install the lathing in dry weather, before laying the roofing material, as wet boards or bars can deform from excess moisture.
