Types and types of mansard roofs, design features - photo
Attic is the attic room, located under the roof of the house, which is equipped and used as a living space. With a light hand of French architects, projects that allow rational use of the roofing space have become fashionable and remain a popular, as well as economically advantageous construction solution. In this article we will understand what types of roof attic there are, what are the advantages and features of using different types of structures.
Constructive decisions
The best option is to include the attic in the design project of the house before the start of construction work. However, it often happens that the conversion of the attic space occurs after several years of operation, when there is a need to increase the useful living space. Experienced builders say that any roof structure can be adapted to the attic, but not every alteration will be rational. The following roofs are suitable for equipment for residential attic space:
- Monopitch Roofs of a shed type are one plane located obliquely due to the different height of the rafter frame or walls. This type is rarely used for the construction of the attic due to the fact that the difference between the length of the walls should be more than 2.5 m. The slope of a large steepness requires strengthening the roof frame and increases the cost of roofing material.
- Dvukhskatnye. Bole rational options for mansard construction based on the roof of the two-ply type. The disadvantage of this solution is that the steepness of such a roof, consisting of two slopes, must be at least 25-60 degrees, so that the room under it is spacious. And the corners formed between the floor and the base of the roof are too small for effective use.
- Broken. Broken mansard called a kind of gable roof, the slopes of which consist of two planes located at different angles. The steep lower parts of the roof increase the usable floor space of the attic, and a gentle top reduces the cost of roofing material. The design of a broken gable roof is more complicated than others because of the massive truss frame.
- Hip and poluvalmovye. This term refers to roofs of the four-slope type, where two slopes are partially or completely replaced with hips. This design allows you to equip spacious attic space and a comfortable ceiling height, but it is used relatively rarely due to the high complexity of the truss frame and the high cost of living.
Important! Developing the design of the house, you need to decide in advance on the nature of the use of under-roof space. Since the attic equipment increases the load on the foundation, it requires strengthening the truss structure and the bearing capacity of the walls. Skilled craftsmen claim that the mansard roof is more expensive than usual, however, additional square meters are more than worth the investment.
Rafter frame
The main difference between mansard roofs and conventional roofs is the change in the roof frame, on which the slopes are supported. Since the design of this type has a lot of weight, increased demands are placed on it. The roof system is under load from roofing material, falling snow, floor beams and attic floor, so all the frame elements are made of durable wood. There are the following types of designs:
- Hanging. Hanging trusses are called trusses, in which the rafters rely only on the ridge girder and the mauerlat laid on the bearing walls. To extinguish the bursting load on the rafters that occurs when using such a system, mount the upper and lower puffs. If the length of the slope exceeds 4 meters, the lower part of the rafter legs propped up with racks or struts that prevent sagging. The dignity of the hanging truss frame is that all the elements are located in the unused parts of the attic, so there is a lot of free space in it.
- Outrageous The suspended truss frame is used in houses, where in the middle there is a supporting partition, which acts as an additional support for the truss legs. On the inner wall are laid wood, an element that performs the functions of the power plate, and install the racks that support the ridge girder. With the help of an overlay system, roofs of a large area are blocked; it is used for roofing materials of great weight (ceramic tiles, slate).
Note! There are design projects of mansard roofs with rafter designs of a hanging and nylon look. To free up space, the frame elements are shifted to the sides, using the crossbar for the ceiling sheeting as the basis for facing the walls. Some architectural styles allow the use of racks and beams as decorative elements, which are an integral part of the chosen style.
Design requirements
Attic is an additional living space in the house, and therefore its construction is strictly regulated by building codes, without which it will be called an attic. To use the under-roof space to accommodate an extra bedroom, nursery, study, or garden, it must meet the following criteria:
- The minimum height from floor to ceiling in a residential attic should be at least 2.3 m according to sanitary standards, that is, the distance between the floor and the ridge of the roof will be 2.5 m or more.
- For equipment of a two-level attic, the distance between the floor and the ceiling should be more than 5 m. Two-level rooms are called attic rooms, consisting of two rooms located one above the other and connected by a staircase.
- In the attic must be present natural light. For this installation of vertical or dormer windows installed directly in the ramp. The cost of skylights is higher, but if properly positioned, they allow the use of sunlight throughout the day, which reduces electricity costs.
- Residential attic space is insulated with effective thermal insulation materials. They are mounted on the gables and slopes of the roof to reduce heat loss when heating a house.
- Attic necessarily be equipped with a system of forced ventilation, working on the principle of convection. It causes the heated, musty air to rise to the ridge of the roof and go out through the aerators, letting in fresh air through the cornices. Due to the constant air circulation in the room, a comfortable microclimate is created, the problem of dampness and stuffiness due to the heating of the surface of the roofing material is solved.
Important! Lightweight coatings are used as roofing material for attic roofs. Metal roofing, ondulin and rolled materials, whose flexibility allows you to easily block broken roofs of mansard roofs, are very popular with roofers.
Mansard roof to make a "zest" in the design of the house, making it memorable and original, without significant cost increasing the living space.