Flat roofs' system solutions

Flat roofings are the most commonly used solution in the case of facilities with large volume, usually for industrial purposes. Formerly, due to the poor quality of the materials used for the roofs’ construction, their regular repair was required. Now, new technologies and materials available on the market allow to execute a lasting and tight coverage for many years.

Flat roofings’ layers

Regardless of whether it is about a new building, or a repaired one, on a flat roof, there must be executed layers ensuring proper ventilation and venting. The proper construction of roofing consists of: structural layer, vapour barrier, thermal and waterproof insulation.

Vapour barrier

The most popular vapour barrier solution is the use of PE film whose task is to protect overlying layers against the ingress of water vapour. Vapour barrier films must be placed under the thermal insulation material in a manner consistent with the principles of their laying on pitched roofs.

Thermal insulation

When deciding on a specific system of a flat roof casing, the investor should pay particular attention to the issue of a proper thermal insulation. The most popular materials used for thermal insulation are: PUR or PIR foams, polystyrene and mineral wool.

When the plates have a variable height, thermal insulation may be a sloping layer. Insulation and sealing systems, in which a thermal insulation layer is stuck with vapour barrier on the one side and with roofing felt on the other one, are more and more often used as well.

The already traditional roofing felts may successfully be used for covering the flat roofs. One of the most modern solutions is asphalt saturated felts modified with polymers resistant to the most extreme temperatures.

Roof of the Sevroll System’s steel hall (see realisation)

Flat roofings’ systems

The most popular system used for flat roofings in industrial halls is a system composed of the following layers:

• PVC or two layers of torch-on membrane;
• thermal insulation (EPS, PIR, wool);
• vapour barrier;
• sheet metal.

PVC membranes are insulation coatings made of hard and soft polyethylene, polypropylene and polyester. The membrane’s function is to protect the roof against moisture or vapour condensation in the insulation layer. It is thanks to it, thermal insulation does not absorb water and does not reduce their insulation properties at the same time.

Sandwich panels

One of the most popular methods of flat roof casing is the use of sandwich panels, in which the insulation is closed between sheets of metal cladding. In this case, an insulating core is polystyrene, mineral wool or polyurethane.

The advantages of this solution include the ease and relatively short time of assembly as well as good insulation without heat bridgings. There are many system solutions used for flat roofings casing.

Selection of the most optimal method in industrial halls depends primarily on, above all, the characteristics of the manufacture, the individual needs of the investor and his or her financial opportunities.