How to build a flat roof with your own hands
A flat roof for small private houses with a small area of the roofing is the task that can easily be done with your own hands. If you wonder how to build a flat roof just follow the simple instructions below.
First and foremost, the mills bearing beams are mounted in wood or steel beams, they redistribute most of the weight of the roof on the main walls and the foundation. The things that you should take into consideration during this stage of work:
- weight of the entire roof and parts of the communications that pass through an attic or are attached directly to the roof,
- weight of the worker building the roof,
- masses of snow in your region and pressure of wind in winter.
Making a flat roof reliable and safe is possible in case of choosing the right roofing materials that will stand the intended physical activity and usual weather conditions and will suite for the house frame. Particular attention should also be paid to the technical specifications of all materials used for the roof construction and the quality of waterproofing and a vapor barrier.
Layers of the flat roof
- The first layer is laying a vapor barrier which protects the insulation layer from absorbing moisture. A vapor barrier is usually made of a polymer-bitumen film reinforced with fiberglass which are attached to the concrete screed. The edges of the film are placed vertically. Overlapped seams are carefully sealed.
- Put a heater on a vapor barrier. If you intend to make a lightweight roof the polymer insulation is fastened directly to the vapor barrier.
- The most important layer for a flat roof is a moisture insulation layer. The best choice is a membrane or polymer-bitumen materials.
The flat roof of reinforced concrete
If the span of the roof is about 13-16 feet, the beams length varies from 5 to 7 inches. Concrete is usually mixed of gravel and cement. These components are taken in such a proportion: 8 parts gravel, 3 parts of cement, 4 parts sand and 2 parts water. If necessary the mixture is poured with a little bit more water. Plank prepared roofing paper to a previously dried roofing surface, then put reinforced mesh periodic profile on it. The quantity of cells must be of about 8*8 inches.
The places where the grid bars are superimposed on one another you should be fixed by a binding wire or glued for the grid from slipping when pouring screed. For the mesh to be completely covered with concrete solutions, put down smaller pieces of rubble. It allows you to create the needed gap between it and the layer of roofing material. Be sure to fill in one lane from the beginning to the end at once. The best thing is filling the entire area of the roof during 12 hours. This will provide the highest quality of your future roofing.
Then you will need to cover the concrete with a film of polyethylene. This is a mandatory procedure if the air temperature is high. Such kind of covering prevents excessively rapid evaporation of moisture from the concrete mix and protects the upper layer from cracking. The concrete should stay under this film for at least three days. After complete drying of the concrete mass, it is poured with a layer of insulation.
Insulation of a flat roof
A significant difference of a flat roof is in the fact that it is possible to insulate the outside and inside after the full completion of the whole range of works. First you should make the outer insulation and start exploiting it. If you find out that your roof is freezed, even a little bit, you might think about the internal insulation of the roof.
The most popular modern material for flat roof insulation is basalt mineral wool. This material is lightweight, it has excellent thermal conductivity and moisture resistance. It is also important that basalt mineral wool doesn’t burn and is resistant to negative influences. All these features combined together make basalt mineral wool the most popular material for thermal insulation of flat roofs.
For internal insulation of a flat roof it is quite rational to purchase fireproof plates made of foam and polyester with a thickness of about 8-12 inches. This is a great option for insulation of the ceiling. Nail wooden slats to the ceiling of the roof with a pitch of about 1-1,5 feet. They are glued on mastic or special glue. The process of internal insulation of a flat roof must be preceded by a mandatory removal of all lamps you have on your ceiling.
We hope this article was useful for you in case you were searching for an answer on a question how to build a flat roof for your house with your own hands in a proper way.
Bentonite waterproofing for protection of building constructions, buildings and structures from water penetration.