Foundation for the roof

Stanislav Freed Without the foundation, as we know, the wall is not set - they simply collapse. The roof also needs to something to build - on the truss system. And this system should be constructed in accordance with the selected roofing material, just as the construction of walls constructed according to the foundation. Initially, the homeowner has to decide a difficult question: Whether the natural tile roof? Cement-sand? Or, to put aside tradition and now use the popular "evroshifer? Oh, you forgot to look at the purse, dreaming, but not figured financial opportunities? Well, then, it is likely you will have to confine ourselves to some relatively cheap option of roll roofing material. By the way, and truss system for roll materials should be made of light weight, because it will not experience large loads. Will not, however, to exaggerate the role of roofing material in the choice of roof system. Yes, this role is essential, but very important, other factors, especially in our northern region, where the weather is severe, as well as unstable and unpredictable. If you have a snowy winter, take a look at some country house, you probably see on the roof of fluffy snow. Or "crust" formed as a result of a succession of frosts and thaws, in a word, there will be a lie or snow or ice. Eye on the mass of snow (or ice) is difficult to estimate, but necessary. Snow load on roofs of large area can be very serious, especially when heavy snowfall, repetitive, and the snow is compressed and forms a larger mass on the roof. And this powerful lot, mind you, the roof must keep, and above all, of course, at the expense of roof system. And in our region are often strong winds blow and have a considerable load on the roof, given the "sail" roof. And once again rescues truss system, which, even in strong gusts of wind can not break the roof in all, the selection and the calculation of roof systems are important as the type and weight of roofing material, and typical of this region, snow and wind loads. There are special techniques of such calculations, and they should be used. But, of course, no need to settle tyk-in-the-butt, must always be some margin of safety, taking into account the rare (but quite possible) force majeure. Not designed for proper load rafters over time will simply crack and break. On the other hand, it is possible to overdo it and so that the roof will withstand even the centuries-old pine tree had fallen. But do so reinsured? As in any case, here it is necessary the best solution without bias to either side. Also, be aware that the roof, rafters, walls and foundation are interconnected, and far more than it seems at first glance. For example, if you decide to use natural tile, first make sure you have enough sturdy supporting structure - namely, truss system. But the rafters rest on the wall, and hence, the walls need appropriate. In turn, the walls are also not hang in the air, they stand on a foundation, and its strength must be calculated correctly. Of rules and regulations! However, the expression "to calculate the correct" - a rather vague, but in this case should be guided by quite specific requirements that apply the system of building codes and regulations. So, your existing SNiPs roof structures shall be designed so that regardless of the weight of roofing material, it will withstand a load of 200 kilograms per square meter. In this figure for our latitude laid snow and wind loads, as well as the safety factor. Supplies needed not only to the case of large wind power or heavy snowfall - to the roof, and they will climb repairmen, who takes away the frost, snow, etc. Further, a more accurate calculation should take into account the peculiarities of a particular roofing material. After all, say, by weight natural tiles and roofing felt different in many times. The choice of roof system is, of course, the type of roofing material. But we should remember that the rafters rest on the wall, and hence, the walls also need to make appropriate. In turn, the walls are also not hang in the air, they stand on the foundation, the strength of which must be calculated correctly. The use of different roofing materials does not affect fundamentally the type of roof system, but makes adjustments to the design. If you select a wood truss system, it must be strong enough to withstand heavy roof (full-or cement-sand tiles). In this case, the rules and regulations prescribe the use of a large section of the rafters - timber 70 at 150 millimeters, move the rafters must be at the same minimal - about half a meter. If you use a lightweight roofing material (evroshifer, shingles), it is recommended that rail section of 50 to 150 millimeters, wherein the pitch of rafters can be significantly increased - up to one to two meters. Given this, we can estimate in advance the cost of materials for the roof system under the roof of a natural tile or roll material. Especially to say about the stage rafters, which depends on the slope of the roof. On average, the rafters set in approximately one meter. In cases where the slope exceeds 45 degrees (and the snow on a roof will not be delayed), the step can be increased up to 1,2-1,5 meters. Conversely, if the pitch is small, step rafters should be reduced to 0,8-0,6 meters. A more accurate calculation can make a specialist who will consider, among other things, a section of rafters, as well as the distance between support bearing structure - struts, braces and ridge girder. Rafters in a country house most reliable option truss system - of course, reinforced concrete or metal rafters. They are durable, strong, able to withstand the most abundant snowfall and gale-force wind of them uneasy. But you just imagine what equipment you will need to raise the roof on a giant cargo. And what need walls to withstand the reinforced concrete roof, and a powerful need foundation! In addition, evidence shows that the walls of houses never constructed with perfect accuracy, so the rafters always have to adjust a little bit in size. And just try to "fit" reinforced concrete structure! Therefore, metal and reinforced concrete structures are mainly used in the construction of large brick houses with heavy roofs of irregular shape. In the overwhelming majority of uses of wood rafter system. The tree is known to be the most eco-friendly material, but also durable, easy to use and easy enough - for lifting him to the roof do not usually require heavy lifting equipment. Wooden rafters can be freely customized, shortened build, bind a variety of ways. In addition, the plank roofing material on a tree is much easier than on concrete or metal. So, the choice made in favor of the tree. Next, make the relevant calculation, bought timber desired section and length, after which the individual elements of roof system installed on the roof with a certain step. One end of the rafter rests on the wall opposite - is attached to the rod skating. Method of mounting truss system on site is a key in a country-house. Becomes the foundation laid walls, and the next logical step - the construction of roof system. Roof design should withstand a load of 200 kilograms per square meter regardless of the weight of roofing material. In this figure laid snow and wind loads, as well as the safety factor. Further, a more accurate calculation should take into account the peculiarities of a particular roofing material. One of the innovations of the last time - installation of roof system in the factory, before the erection of walls. Now the factory produced even at home, and the geometric precision of the buildings has increased, and therefore can not really have to worry about fit and podtesyvaniya rafters. Plus production under the roof truss system are obvious: if the construction site, for example, rain or snow, neither of which installation can not be considered. And in the factory - please collect it in any bad weather! Again, working at a height of seven to ten meters, so even on an inclined plane is not always possible to meet the desired precision assembly. While in hospital, and accuracy, and adaptability to withstand the process easier. In addition, this type of production involves a more reliable and durable connection between the elements of truss system. At the factory rafters gather in large structural elements - the farm - with the help of special butt straps or, in other words, the nail plates. These bar-pressed plates using a powerful press in the rafters, which subsequently virtually eliminates movement of elements of truss system with respect to each other (in a conventional roof system to the extent of drying such a move, alas, inevitable). Continue to prepare the farm are delivered to the construction site, where they were quickly collected into a single system. It is clear that at this time of installation is minimized, work itself can be simplified, and the materials essentially saves. It should be noted that such a serious and responsible operation as impregnation of wood preservatives and flame retardants in the factory to carry out much easier. But the chemical treatment depends on longevity of the roof and the house itself as a whole. Breeze under the roof In conclusion, we recall that with the installation themselves rafters of the roof does not end there. Kontrobreshetku need to do, which is mounted along the rafters, repeating their pattern. After that is fixed across the rafters purlins - that it will subsequently plank roofing. Construction sheathing, as well as the construction of roof system is largely determined by the type of roofing material that is applied in a particular case. If your choice was, for example, on a ceramic tile, the lathing should do a section of bars 50 to 50 or 60 by 60 millimeters, which are placed at a certain distance from each other. If you use a light roll material it is made from thin solid flooring boards or waterproof plywood. For wood crates for special requirements: it must be well dried, so that in future there was warping and, accordingly, the deformation of the roof. Metal and reinforced concrete structures are mainly used in the construction of large brick houses with heavy roofs of irregular shape. In most cases, use of wood rafter system. Double crate lifts roofing material over a layer of waterproofing and provides a constant draft in the underlay area, its ventilation. And that means that got there the atmospheric moisture or water vapor from the house will be easily blown out, and construction, thus not zagniyut. Even when using a material with low thermal conductivity in the underlay area still condensation, which after a while insulation can break, and will also help to reduce the lifetime of most truss construction. Construction of the truss system - paramount construction phase. And this "foundation" for the roof determines if not all, almost everything. How responsible you approach this issue, and so lives in the house is comfortable and hassle-free.