An mansard type of roof is an excellent option to increase the useful area of a private house. The dimensions of the additional room will determine the shape and type of the mansard roof. The geometric shapes of such a roof can have a different configuration, and the roof itself can cover the entire building or a small part of it.
Types of mansard roofs. Photo with a functional roof
There are several varieties of mansard roofs:
- broken line.
Shed mansard roof. Mansard roofs in a single-handed version look peculiar. Such designs are quite simple in construction due to the lack of a ridge and the difficulties that its arrangement entails. The mansard is formed due to the different heights of the walls on which the beams of the structure rest. The mansard floor under such a roof is rather miniature.
Symmetric mansard roof. This type of roof is built on the basis of a gable model. The walls of the mansard in this embodiment will have the same width and height. This form provides the possibility of installing indoors full-fledged window structures and doors leading to a balcony or terrace.
Asymmetric mansard. Such roofs are obtained as a result of hip placement of slopes. Keep in mind that a room under an asymmetrical roof will have a small area. The outlines of the opposite walls of such a room will be as follows: two in the shape of a triangle, two in the shape of a trapezoid.
Tent mansard design. A room under such a roof can have a specific configuration: round, conical or pyramidal. In this regard, it is very difficult to enter windows or doors into the walls of such mansards. Window structures of this form will need to be made to order according to a special project, which will cause a significant increase in the cost of construction.
Useful advice! When arranging window structures in the mansard, pay attention to how they will open. Windows that open in and down can cause injuries to the person who opens them. Opening the window outward with the handle located above is optimal.
Broken roof. If you want to make maximum use of the space under the roof, the choice of a broken roof will be the right one. In this case, it is possible to significantly reduce the so-called dead zones, the area of which cannot be used as useful. Thanks to external fractures of the faces, the mansard space can be expanded, while the choice of a straight roof limits the rational use of the space under it.
The broken roof structures are distinguished by the small height of the walls of the rooms that have turned out under them. Installation of such a roof is justified when the mansard is built on an already erected building. In this case, you don’t have to worry about the additional load on the foundation, the project of which did not initially presuppose the existence of an additional residential floor.
A roof is considered popular, the design of which is based on triangular figures: upper and lower. The design scheme of the upper triangles involves both a hanging and a layered rafter system, and the bottom – only a layered one. The upper slopes are based on isosceles triangles, and the lower have two rectangular triangles at the base.
Mansard roof insulation and waterproofing
The design of one or another mansard roof depends on the load to which the roof will be exposed above and below. Do not forget that warm air flows rise and settle in the form of condensate on the inner surface of the roof. Therefore, the technology of erecting mansard roofs of private houses must necessarily take into account high-quality heat, steam and waterproofing.
Useful advice! When constructing an mansard roof, pay attention to the distribution of ventilation risers and chimneys: do not allow them to be located in the valleys.
In order to be comfortable in the mansard, it is necessary to use a heat-insulating material that will contribute to this regardless of the time of year. If the roofing cake is made in compliance with all technological rules, the indoor climate will be normal.
To make the right choice of thermal insulation materials will help knowledge of their basic characteristics, which include:
- resistance to temperature extremes;
- low thermal conductivity;
- moisture resistance;
- invulnerability to mechanical stress;
- environmental friendliness;
- fire safety;
- density up to 250 kg / m³.
The technology of thermal insulation in the mansard is similar to the insulation of ordinary roofs, however, due to some criteria, increased requirements are imposed on it. The role of the walls in the mansard rooms is performed by slopes and pediments, due to which they overheat in the summer and quickly cool in the cold season. Therefore, the sequence of layers of the cake must be strictly observed:
- Vapor barrier.
- Insulation material.
- Ventilation (air) clearance.
- Waterproofing layer.
- Roofing coating material .
Using a heater, you should pay attention to its thermal conductivity (the ability to retain and transmit heat). The lower the thermal conductivity, the better the material will retain heat in the room, protecting it from cooling. Mansard roofs are more prone to heat loss in the winter, as heat flows upward, approaching the roofing.
In winter, the following process is observed: the snow covering the roof surface performs the function of a kind of heat insulator. If the heat loss is large, the snow on the roof begins to melt, turning into a dense crust of ice, which does not retain heat and creates an additional load on the roof. Properly laid insulation will prevent snow melting and ice formation.
In extreme heat, the mansard room becomes very hot. To avoid this, they arrange thermal insulation from the inside. The number of layers for internal protection depends on the properties of the material. For these purposes, they usually use: polyurethane foam, mineral wool, extruded polystyrene, slag wool, glass wool, foamed glass. From natural heaters, straw, slag, wood shavings, reed panels will be used.