Of all the roofs being built, gable roofs are the most popular. This is explained by the fact that it is relatively simple in execution and at the same time successfully copes with wind and snow loads.
But in order for it to be reliable, it is necessary to correctly determine the thickness and length of the rafter legs, as well as the method of attaching them to the Mauerlat and the ridge. It is necessary to take into account the weight of the crate, finish coating, insulation, and possibly skylightsespecially if they are going to be large. The strength of the entire structure depends on these calculations.
Rafter systems. Kinds
There are two types of truss systems. Hanging and layered.They differ in that with a hanging system, the rafters rest on the Mauerlat, and the layered system has a third point of support in the form of a capital partition inside the building. Also, the rafters of the layered system can be reinforced with vertical posts and slopes. The support for them will be floor beams or a bed.
The hanging system is used on houses and buildings up to 6 meters wide, while the layered one has no such restrictions.
Mauerlat. Purpose
Mauerlat is the foundation of the roof. It takes on all kinds of loads from the truss system, both vertical and thrust, as well as the weight of the entire structure.
This reduces the load of the entire structure on the outer walls, protecting them from deformation and cracks.
Mauerlat is made from a powerful bar 150x150 mm, or from a wide board from 180mm to 200mm with a thickness of 50mm.
Mauerlat mount
Particular attention is paid to fastening the Mauerlat to the wall. It all depends on the material from which the outer walls of the house are made. If they are made of brick, then additional work is not necessary. But if aerated concrete blocks of weak strength or foam concrete were used, then it is necessary to strengthen the base under the Mauerlat.
In this case, a reinforced monolithic belt is mounted around the entire perimeter of the outer walls, and studs and rolled wire 6 mm thick are laid in it to fix the Mauerlat.
When building brick walls, a reinforced belt is not needed. For 3 rows to the top, a wire with a large overlap is laid in several places or eyelets are installed in the walls to which this wire is then attached, being a reliable fixation of the base of the truss system.
Preparation of the base for Mauerlat
Before laying a beam or board on the plane of the wall, it is necessary to prepare the base, clean it from the influx of concrete, and then lay the roofing material in two layers along the entire length, thereby ensuring waterproofing.
It is desirable that the Mauerlat does not have joints along the entire length, but only in the corners, then it will be stronger.
We fasten it to the wall with wire or studs, having previously drilled holes in the board or timber.
Rafter legs. Manufacturing
After the Mauerlat is fixed, mark the places where the rafters are attached to it. Usually the distance between them is 1 meter. The rafters are made from boards 150-180 mm wide and 50 mm thick.
First, a template is made from thin and light boards in the form of a triangle. Then, on the ground, according to this template, the required number of rafter legs is made. Between themselves, the rafters are fastened with overlapping nails or with the help of a washed down half the thickness of the tree. Raised to the roof using ropes.
Installation of rafters
Begin the installation of rafters from the extreme ones from the pediment. The rafter legs are set according to the level and plumb, for the convenience and accuracy of installation to the walls, where the pediment will be, boards with an overlap above the roof are fixed. They serve as an additional guide for the correct installation of the outer legs.
Fastening rafters to Mauerlat
At the bottom, the rafters are attached to the Mauerlat, having previously washed down in it. But it is possible to file down the Mauerlat only 1/4 of the thickness, so as not to weaken its strength. More often, they wash down on the leg at such an angle that it fits tightly on the Mauerlat. Fasten together with brackets and corners.
Pull the twine along the bottom of the rafters and the top on both sides.This is a guideline for installing the rest of the rafter legs. The vertices are connected using a ridge run.
Install slopes and vertical racks for rigidity and reliability of the entire structure.
Such a roof will reliably perform its functions and confidently cope with extreme weather conditions.
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