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Wells, septic systems and radon: technical checks for rural houses in Sweden and Finland

Published 13 November 2026 · By the Cheapaco editorial team

Most cheap houses in the Swedish and Finnish countryside are not connected to municipal water and sewage. They have their own well and their own wastewater system. That is normal, but these systems can be expensive to fix, and there is a third invisible issue to check: radon.

The well

There are two main types: a drilled well (borrad brunn, porakaivo), which goes deep into the bedrock, and a dug well (grävd brunn, rengaskaivo), which is shallower and more sensitive to surface water and dry summers.

If there is no recent test, have the water analysed by an accredited laboratory before you buy, or make the purchase conditional on it.

The wastewater system

Rural houses typically have a septic tank (slamavskiljare, saostuskaivo) followed by a soil infiltration system or a small treatment plant. Municipalities in Sweden and Finland set rules for these systems, and older systems may not meet current requirements.

Radon

Radon is a radioactive gas from the ground (and, in Sweden, from some building materials such as blue lightweight concrete, blåbetong). It has no smell or colour and long-term exposure increases the risk of lung cancer. Both Sweden and Finland have areas with high radon levels.

The radiation safety authorities (SSM in Sweden, STUK in Finland) publish the reference levels and advice on measuring.

Who checks what?

In Sweden, the buyer has a legal duty to inspect the house, so problems you could have discovered are usually your responsibility. A standard building inspection does not always cover the well, sewage or radon, so ask for these specifically. In Finland, a condition inspection (kuntotarkastus) is common; again, check what it covers.

Read the Sweden and Finland buying guides, or browse cheap houses in Sweden.

Official sources