Sealing of structures

Sealing of ground-supported structures can block the flow of radon into the house. However, it is practically impossible to find or seal all possible leaks. Therefore, sealing as the only mitigation method is usually not sufficiently efficient.

Mitigation measures have often been supplemented with ventilation-based measures. The ground-supported wall of a house with a cellar – or a hillside house – built of porous lightweight concrete blocks is sealed with fine concrete plaster.

In low-rise residential buildings with wooden load-bearing wall structures, sealing has usually reduced the radon concentration by 10–20 per cent. When combined with improved efficiency of ventilation, the radon concentration has fallen by 20–40 per cent.

Polyurethane-based elastic joint sealing compounds and waterproofing compounds can be used for sealing the gap between the floor slab and footing. The manufacturer’s instructions must be followed. Widening of gaps and cleaning of the area of adhesion are essential parts of the work.

The cost of sealing varies greatly. The most significant cost items are the preparation work, material costs and joint sealing.

Share this page