Roof Layer Fixing

Roof Layer Fixing

A lot has been said about the importance of such a structural element of a building as a roof. From its features depend the architectural appearance, protection from the weather and the durability of the house.

The roof has a layered structure, it is the so-called roofing “pie”. Each layer in it has a specific function, but it is very important that they are placed in the correct order. Any mistake made during their construction can negatively affect the performance of the roof and its durability. In each case, our specialized roof designers will help you determine the right material and structure of your roof layering.

Regardless of the type of roof insulation and its shape, the layers of the roof are always the same and are arranged in the same order. The general construction of the roofing “pie” is so versatile that it is not affected even by the climatic conditions in the construction area and the chosen roof cover.

Roof layer fixing
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Roof Layers

Here are the main layers of the roof in the order of their installation from the inside to the outside:

  • Vapor barrier
  • Insulation
  • Waterproofing
  • Counter purlins with purlins
  • Roof covering

Vapor barrier

A vapor barrier on the roof protects the roofing “pie” from moisture ingress from the building. We are talking about water vapor, which is quite a lot in the air, not only outside, but also inside the house. The easiest way to verify this is with a room hygrometer – it shows how much moisture is in the air. Even in a room overheated by heaters, humidity rarely drops below 15%, and the lower limit of the norm is almost three times higher – 40%.

The vapor barrier is made of materials with very low vapor permeability, which effectively block water vapor. Regardless of the type of vapor barrier, our specialized roofers make attention to its hermetic attachment.


When the roof is cold, then another 20-25% of the heat goes through it. We offer you an easy way to reduce these heat losses by adding a layer of thermal insulation to the roof “pie”.

The following requirements are imposed on thermal insulation:

  • low thermal conductivity;
  • ecological safety;
  • flammability;
  • volume weight;
  • soundproofing properties;
  • vapor permeability;
  • stability.

Insulation has no heating properties at all, it simply keeps air in the fibers and in this way saves heat. The range of thermal insulation materials is quite large, but our specialists will help you to choose the right material according to the features of your roof.


Waterproofing layer performs two functions at the same time: protects thermal insulation from moisture that can get into it during a leakage; through it, excess moisture is removed from the thermal insulation.

The simplest waterproofing is the same polyethylene or propylene material. But nowadays, waterproofing diffusion membranes are much more often used – materials that keep moisture coming from outside, and at the same time freely pass water vapor.

Counter purlins and purlins

These are two frame elements in the construction of the roofing “pie”, which are needed to attach the roofing covering. But they have different tasks: The counter purlin is attached to the rafters parallel to them. It presses the waterproofing and provides ventilation inside the roofing “pie”. The purlin is attached over the counter purlins perpendicular to the rafters.

Roof cover

This is the finishing layer of the roof. On the one hand, it must withstand regular contact with water and a heavy load from the snow and ice in winter. On the other hand, to be aesthetic so that the roof has a good appearance. Any way you don’t need to worry about the right choice, our professional team will help you to make the right decision.

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