Moisture through leaking ground level zone

The biggest cause of moisture problems in houses is not occupants behaviour, but the not waterproof ground level zone.

The imperfect waterproofing of the ground level zone, this is the first 20 – 30 cm under the level of the pavement or garden, is the biggest cause of all moisture problems in all buildings, worldwide.

With a simple calculation in quick maths we quickly get a lateral flow of rainwater of 1L/minute with a house of 10 x 1m (= 40m circumference), with a continued rain poor. 1L/minute x 60 minutes x 24 hours = 1.440 litre rainwater per day that streams horizontally into the house.

Reserved this gives an average of 0,25L/min x 24h. So with a rowhouse of 5 metres wide this gives a lateral infiltration of minimally 10m (2x5m) x 60 minutes x 24h = 360 litres per day.

If you compare this to the maximal own moisture production of 2 litres per day, per person, you see that you have to forget occupants behaviour and deal with the ground level zone immediately.

A lateral (horizontal) infiltration of rainwater in a quantity of 1L per minute is a very careful estimate. With a greasy soil or a totally saturated ground level zone this will obviously be much more.

You can visualize this by poking a hole in a water bottle of 1,5L. See how much water runs through the not waterproof ground level zone.