The roof that crowns the house must be as reliable as all other structures. However, mistakes in the construction of the roof are quite common. Our advice site decided to choose the most common ones so that you can avoid such problems during roof construction..
The first mistake
Lack of a project, construction documentation. Even if you found on the network a typical project of a private house, the portal wrote about the pros and cons of which the portal in detail should be drawn in detail, described, all key details. And the features of the roof as well! Otherwise, if you are building a house simply from a magazine clipping without involving an architect, the result may be questionable. You can’t start building a house without understanding what kind of roof it will be. It should be in harmony with the facade, layout, and other structural features. Therefore, a preliminary plan, a project with an accurate calculation of the required amount of materials and design features is necessary.
The second error
Choose the wrong roof covering. For example, slate roofs and natural tiles require a sufficiently large slope, otherwise it will be difficult to ensure tightness. For roofs of a complex structure, with a large number of corners, protrusions, abutments, domes, metal tiles should not be taken – there will be too much waste, there will be problems with joints. In this case, it is advisable to stop at a soft roof, bitumen-based materials. In addition, the weight of the roofing should be taken into account, for heavy cement-sand tiles, for example, a reinforced base is needed. In any case, the choice of roofing material should be dictated by the characteristics of a particular project. And the color of the roof should be in harmony with the facade finish.
Insulation cracks. It is very important to ensure that the insulation boards fit snugly against each other. Otherwise cold bridges will appear, and all the work will be done in vain. Mats and slabs are laid flat, you need to leave a centimeter of allowances in width, so that a snug fit to the rafters is ensured. Align the insulation along the bottom of the rafters. In the case of laying two or three layers of insulation, the joints of the upper and lower plates should not coincide. Another important point – do not forget to insulate the wall located behind the Mauerlat. Yes, this is a hard-to-reach place, but it also needs to be insulated, otherwise a significant defect in the thermal protection of the whole house will appear.
Forget about vapor barrier or apply it incorrectly. The “cake” of roof insulation must be performed in accordance with all the rules, otherwise dampness may appear, which will lead to deformation of the rafters. Use construction films and membranes and lay them in such a way as to ensure tightness. Yes, it is difficult to do this in places of abutment to walls, skylights and ventilation pipes. But you need to! Use a special mounting tape to seal the joints of the vapor barrier to the structures and joints. And don’t let the under-roofing film be laid inside out! It is always sold face-to-face inside the roll, with an overlap stripe on it..
Forget about ventilation or make it ineffective. This can lead to condensation under the roof, moisture and related problems. It should be borne in mind that the area of supply and exhaust ventilation must correspond to 1 / 250–1 / 500 of the area of insulation. If we are talking about the ventilation gap of the eaves, then it must be at least 0.2% of the area of the roof slope. This can be achieved both by installing roof fans, aerators, eaves and ridge vents, and by creating special ventilation gaps between the insulation and the insulating film.
Uneven lathing. This is an indispensable element of the entire roof structure. The construction method and the type of lathing must correspond to the roofing. If the step is increased, there are irregularities, then the finish coating will be installed inaccurately, the joints will be leaking, the fasteners will be weak. It is important to remember that, for example, for metal tiles, the sheathing step should be 50×50 millimeters, and for roll materials, bituminous tiles, you need a continuous flooring of thin boards or moisture-resistant plywood. For slate roofing, the section of the lathing is 40×60 mm..
The joints are not sealed. In particular, around the chimney, we have devoted a separate article to this topic. For example, tape is often glued directly to a dirty roof surface. And she moves away! Or the special clamping bar is not used. Remember that the junctions are the most vulnerable point of the roof and they need to be given special attention..
Do not arrange drainage. Necessarily need rainwater, gutters, drainpipes. It is not so difficult to equip a drainage system, but there are many benefits from it. Without drainage, the walls of the building will be humidified, leading to problems. The number and size of all elements of the drainage system must correspond to the characteristics of the roof, its shape, type of coating. Pay special attention to ventilation risers in valleys, narrow eaves, slightly sloping ramps, protruding dormers and parapets. That is, everything that can create obstacles for water flow.
Save on components. Manufacturers offer everything that is needed for arranging the roof, including skates, aerators, gratings, air vents, fences, snow pads … But often the owners decide to save on this, make, for example, a valley with their own hands from galvanized steel. And problems arise. We advise you to buy everything you need for your roof, agreeing on a complete set with the seller and installers.
Walking carelessly on the roof. Problems can arise even during installation, and then during the repair of the roof. Shoes with soft, non-slip soles are essential. In addition, you must not step on places under which there is no crate, and crests of “waves” of wavy materials, such as corrugated board and euro slate.
We are sure that thanks to our article you will try to avoid the listed mistakes when building a roof and will do everything right..