Dampness problems in your (semi-)basement

How can you recognise humidity or dampness problems?

• brown stains on the walls (mould)
• peeling wallpaper
• tearing or cracking drywall
• damp or wet basements

Basements which are not used as a living space do not have to be waterproof. However, it is still important that there is an ample flow of fresh air.

Causes

Dampness or leakages in basements can have various causes:

• The groundwater level is temporarily higher, causing dampness in your basement. This is how you will find out that your basement wall is not, or no longer, waterproof.
• The basement walls have tears, allowing ground water to enter. Subsidence (the sinking or settling of the ground surface), vibrations or ageing can cause these tears.
• A window or door in your basement is leaking. This allows rainwater to enter.
• Dig a trench or install a trench drain system to collect and drain rainwater away from your home. Or install a sump pump in your basement. A sump pump is a pump used to remove water that has accumulated in a water-collecting sump basin. It can pump the water away from the building so the water flows into the sewer system.

What actions can you take?

You can change the layout of your basement, read the tips given by Amsterdam Rainproof () here. You can also decide to waterproof your basement. This option can be very complicated and costly. Ask a contractor for information or contact your landlord.

Advice on groundwater problems

Waternet gives advice on groundwater problems. Therefore, we measure the groundwater level in many spots in Amsterdam. Groundwater levels vary: sometimes they are higher than normal and sometimes they are lower.