Leaking ducts lead to involuntary ventilation. The air is transported within the building in a way that is not planned, and this has negative consequences on the indoor environment.

If a self-drafting system takes in air from spaces other than the apartments, it means a considerable deterioration of the air circulation.

In a system with mechanical exhaust air, you can have problems with negative pressure in the apartments and increased energy consumption for the fans.

We seal the ducts with composite pipes (free from toxins) to ensure a good flow and a good indoor environment.


The material

The composite pipe has a base and can be made of water-based non-toxic thermosetting resin. The composite material is unique and can be made to measure in various dimensions. The nature of the material is to be able to take any shape, and can be used in all types of duct systems such as

  • sheet metal channels
  • Asbestos ducts
  • Molded channels
  • Walled channels

The products have been carefully tested and achieved the highest tightness class D according to the European standard SS EN 12237.

The products meet strict requirements in terms of fire resistance and insulation. The insert pipes are strong, light and provide perfect insulation. The material has very low roughness, which provides low friction that guarantees high flow rates, better traction, minimal soot accumulation and fouling in the renovated channel. The composite material works with all types of surrounding materials.

The material has been tested and proven for many years and has met the strictest environmental requirements placed on goods for the construction and real estate sector. The products are non-toxic and environmentally friendly throughout their entire life cycle.


With a camera, we do a thorough examination of the ventilation duct. Dimension, length and angles are checked. Access to the canal via the roof/attic as well as the don in the apartment is a prerequisite. In the event of an obstruction in the channel, this is cleared away. Don is dismantled in the apartment.


After the inspection has been completed, we inform all parties concerned about what we are going to do, schedule and points of reference. Of course we answer all questions. All information to the residents is first anchored with the client.

Ventilation i hemmet


The flexible lining is inserted into the canal. Once the liner is in place, the liner is pressurized and expands. The lining is then cured until the thermosetting water-based resin has polymerized completely. The lining becomes self-supporting.

Control & Documentation

When the renovation is completed, the quality of the completed renovation is checked with a camera. All channels are documented with traceability on the control plane. The device is then installed back in the apartment. And it is hardly noticeable that we have been there.


Finally, the documentation is handed over to the client. All material documented on a signed control plan for all channels to the property owner/client, in connection with approval of the renovated ventilation system. The documentation constitutes a guarantee and is of great help in the event of any need for future work in the system.