15 cm of Styrox (thermal insulation) has been already placed on the floor when I realised that pipes for radon were not placed in the ground. Bummer. Totally forgot about it.

Radon is a radioactive gas that accumulates in constructions with no or little ventilation and is a health hazard. It is claimed to be second most frequent cause of lung cancer after smoking. Radon is emitted from the ground in the regions with soils containing granite, which Southern Finland definitely has plenty of.

Good deal that these pipes need to be installed only along the walls, so not all of Styrox plates had to be removed. But a lot of extra work anyway. Learning how to build houses the hard way…