Concrete cellar plus bitumen?

Hello and a happy first Advent!

Our shell is about to have its roof covered, the WU concrete basement is still open, meaning the soil has not yet been backfilled. We have integrated a drainage system from the company Drytech in the basement.

Yesterday the neighbor suggested that we should have our residential basement painted with bitumen on the outside, as this would make the climate in the residential basement more pleasant. (Through concrete, moisture would normally diffuse, which would be harmless for a storage basement, but rather unpleasant for a residential basement.)

What do you think? Is that true? How expensive could that be?

Thank you very much and best regards!

Hello,

Our shell is about to have the roof covered, the WU concrete basement is still open, meaning the soil has not yet been filled in. We have integrated a drainage system from the company Drytech in the basement.

You probably mean drainage laid around the basement

Structural waterproofing: watertight / impermeable to water

The required waterproofing measures result from the watertightness of the existing soil or individual soil layers as well as from the height of the groundwater level. This information can be obtained through appropriate soil investigations (soil reports). It should be noted that the long-term (over several years) highest groundwater level is determined for the groundwater level. For a first assessment, some responsible authorities also provide information about the groundwater level.

Regarding loading, a distinction is made between:

Soil moisture and non-accumulating seepage water in sufficiently permeable soil as well as the highest groundwater level below the foundation level, accumulating seepage water in soils with lower water permeability (cohesive soils) and without drainage, if the highest groundwater level is at least 300 mm below the foundation level (i.e. if soil type and terrain form only suggest stagnant water) and for a foundation depth up to 3 m,

or

pressing water in buildings whose foundation level lies below the highest groundwater level or in the perched water, regardless of foundation depth, immersion depth, and soil type.

Yesterday the neighbor said we should have our living basement painted with bitumen on the outside, which would make the climate for the living basement more pleasant. (Moisture would normally diffuse through concrete, which would be harmless for a utility basement but rather unpleasant for a living basement.)

If it is a WU concrete basement, it will be waterproofed according to the results of the soil report; then no further measures are necessary and you can forget your neighbor’s statement.

What surprises me more is your statement "living basement" – does your builder know about this? Because then insulation materials must be installed in the soil around the basement according to statics/thermal protection verification. The normal waterproofing according to DIN for WU concrete is certainly not sufficient here; by the way, the neighbor’s statement in this context is also worthless

Kind regards

Thank you first of all for the response!

I have looked up the following data again.

1. We have a soil report stating that earth-contacting building components must be protected against temporarily accumulating seepage water according to DIN 18195-6. Alternatively, the installation of a drainage system according to DIN 4095 is possible.

2. Our energy consultant has specified for the WU concrete cellar
a) cellar walls with 10cm insulation outside 035,
b) floor slab with 12cm below 035, 5cm insulation above 035, 5cm insulation above 025. The general contractor has adopted the energy consultant’s specifications. We have also submitted the soil report and cited it as a requirement in the contract.

Are the conditions for a habitable cellar therefore met?

Best regards!