Flat roof of a private house do it yourself - device and

21-02-2018

Roof

The construction of a dual-slope or hip roof is not always rational and expedient when it comes to commercial buildings, industrial and commercial facilities, and sometimes private houses in a modern style. The high consumption of material, complex truss system make the construction of these structures economically unprofitable, protracted event. While projects with a flat roof significantly reduces construction costs, is built quickly and is suitable for almost any buildings.

House with a flat roof надежным образом защищен от повышенной ветровой нагрузки. Однако, не имея скатов, он не может оперативно отводить дождевые и талые воды с поверхности кровли. Ситуация усложняется тем, что поверхность кровельных материалов имеет шероховатую структуру, которая не позволяет влаге и снегу свободно соскальзывать. Поэтому устройство плоской крыши, смонтированной своими руками, должно соответствовать жестким требованиям строительных норм к гидроизоляции, разуклонке и технологии возведения.

House with a flat roof

The structure of the roofing pie

The need for a high level of protection from moisture makes the roofing materials of a flat roof lay down, one above the other, forming the so-called “pie”. If you look at its device section, you can see the following layers:

The structure of the roofing pie flat roof

Flat base, made of concrete slabs or sheets of profiled metal. It provides the rigidity of the structure, bears the weight of the roofing pie, transferring it to the bearing partitions and, as a result, the foundation. For a roof being used, the base should be as rigid as possible.
Vapor barrier. A layer that is necessary in order to protect the flat roof from the penetration of vapors from the inner heated rooms into the insulation layer. By settling on thermal insulation in the form of condensate, water irreversibly reduces its insulating properties by more than two times. As the simplest vapor barrier using plastic film or coatings based on bitumen.
Insulation. For thermal insulation of a flat roof, filling materials such as expanded clay, perlite, slag, rolled, for example, mineral wool and in the form of slabs, in particular polystyrene foam, are used. By the way, the insulation is used not only to regulate the temperature, but also to unravel the house with a flat roof. The main requirements for insulation - low hygroscopicity and thermal conductivity, light weight.
Waterproofing. Flat roof allows you to use for the coating to protect against moisture rolled materials: bituminous, polymeric and bitumen-polymer. In addition to high waterproofing qualities, they must be resistant to temperature changes, elasticity, long service life.

Types of roofing and nuances of their installation

The flat roof device determines the design and nature of use. In the separate types demanding a special approach at construction emit the following:

Not exploited. They imply that in this case the flat roof will not be used constantly, if there are people on it, then only for inspection and repair. Therefore, profiled metal is used as a base. Projects with an unexploited roof are most relevant for a garden house.
Operable. The concrete base of the operated roof gives stability and rigidity, therefore such a device is suitable not only for finding people, but even for organizing parking or a pool device. The main feature that should be taken into account is the slope of the roof being used, it should not exceed 2-3 degrees, exceeding the recommended angle reduces the safety of using a flat roof. Projects with an exploited roof are suitable for commercial buildings.
Inversion. It differs from the traditional reverse order of layers of the roofing pie. That is, waterproofing is reversed with thermal insulation in order to protect the fragile moisture barrier. For private construction, architects recommend projects with an inversion roof.
Ventilated. The peculiarity of its installation is the device of aerators necessary for evaporation of moisture from the thickness of the roofing pie. Projects of this type are used for roofing a large area.

Puddles on the surface of a flat roof

Installation of the roof for unheated buildings

If a flat roof is erected with its own hands for an unheated utility room, for example, a shed, a gazebo, a shed or an extension, the slope is organized with the help of support beams. They are set at an angle of 3 degrees, which is 30 mm for each running meter of the beam length. Then on the beams lay the base of the unedged boards, fixing them with nails or screws.

Installation of flat roof in the garage

Ruberoid is used as a waterproofing material - the most affordable material. It is produced and sold in rolls. Carry out cutting waterproofing, cutting strips so as to lay them in the direction of the slope of the flat roof. Strip roofing material gradually lay with an overlap of 10-15 cm and fixed with wooden slats or steel bars every 60-70 cm in the direction of the drain, so as not to block the path of draining moisture. The flat roof of an unheated room can be easily assembled with one's own hands, even by one worker without the help of utility workers.

Installation of roof for heated constructions

If a private house with a flat roof is being built, which is planned to be connected to the heating system, then the works are carried out in the following order:

Install the floor beams, strictly observing the horizontal. The spans between the beams should not exceed 0.9-1.0 m. It should be noted that the device for covering large spans alone is inconvenient, the help of ancillary workers is required. Flat roof - one of the easiest options for the construction of their own hands.
On the supporting beams need to make the flooring of unedged boards with a thickness of 40-50 mm. The greater the distance between the support beams, the larger cross-section choose lumber.
Stripes of roofing material or other waterproofing material are laid on the wooden base. After the cutting of the waterproofing has been performed, it is laid out on a flat surface so that it can lie down and smooth out. To prevent a house with a flat roof from leaking, ruberoid is laid in stripes, overlapping them at each other by 10-15 cm.
The next stage of building a house with a flat roof is the filling of expanded clay, slag or perlite. Not knowing how to properly form the slope of the roof, you can provoke the formation on its surface of puddles, leaks and reduced service life.
Then it is necessary to fill the insulant with cement milk, a layer of at least 2 centimeters. This process is called a screed; it takes 1-2 days to dry.
After drying of the screed, a primer is applied on it on a bitumen base, after which the roofing material is laid and glued.

Bitumen based mastic coating

To build a house with a flat roof, the length of which exceeds 6 m, for the manufacture of support beams, a timber section of 150x150 mm or more is used, or a steel I-beam.

Monolithic concrete roofing

Another option is to build a flat roof with your own hands - the use of monolithic concrete. The process is as follows:

I-beams made of steel with a thickness of 12-15 cm are used as floor beams. They are laid horizontally without forming a slope.
Experienced roofing masters recommend using brand 250 concrete, kneading it better in a stationary concrete mixer, on site. Stirring by hand, it is very difficult to achieve the necessary consistency. The “recipe” of concrete is simple: take 4 buckets of small gravel (20-20 mm), 1.5 buckets of cement, 1 bucket of sand and water.
The base boards are fixed to the lower shelf of the I-beam and covered with a layer of roofing material and reinforced mesh (cells 20x20 mm).
They fill up the reinforced mesh with small gravel and pour it with prepared concrete. An important caveat - you need to have time to fill the entire surface of the roof during the day, so that the screed comes out quality.
Drying of the screed occurs within 1-2 days, for which it is better to cover it with plastic wrap to prevent premature evaporation of moisture. If this is not possible, and the weather is hot, from time to time, water from the roof surface is followed.
After drying, the expanded clay is poured and its back is filled, and a ballast sleeve made of paving slabs is laid along the perimeter.

Razulukka flat roof claydite

Unraveling process

Razulukka flat roof - a device of a small angle of the roof surface for the organization of drainage. Before building a house with a flat roof, it is better to determine in advance which drain you will install, internal or external, and make a drawing. If an internal drain is provided, water should be drained using a leveling device into water catching funnels, which have 1 per 25 square meters or more. If you do an external drain, the moisture should fall into the gutter. Razlonlonku form the following methods:

Pouring material. Expanded clay or perlite fall asleep so as to form the recommended flat roof slope and pour cement milk.
Thermal insulating material. Insulation plates are laid so as to set the angle of the surface of the roof, that is, the layers at the base will be less than that of the ridge.
Concrete pouring. Concrete is poured into a pre-equipped formwork, which is adjusted to a certain angle.
Plastic panels. To create the slope of the roof using special panels made of plastic, different in thickness. This is probably the most expensive way to unravel.