Which interior plaster to use for a concrete basement

Hello Tobi,

we are still considering whether to take a concrete cellar or just a black tank. The soil report recommends at least a black tank. However, in the neighborhood, almost only concrete cellars have been built.

You are mixing up the terms. Take a look here:

Which waterproofing tank is the right one for which sealing?

In waterproofing technology, two basic types are currently distinguished:

Surface waterproofing, where materials applied on the earth-facing side of the construction are supposed to prevent moisture intrusion. Since in the past almost exclusively bituminous materials were used, the term Black Tank has become established for this type. Recently, sealing materials based on plastics are also used.

Rigid waterproofing, where the supporting structure itself, in addition to its actual function of load-bearing, also takes on the waterproofing tasks. For the production of the required watertight concrete, blast furnace cements are often used, which produce very light-looking building materials. This appearance has given the so-called "concrete cross-section waterproofing method" the name White Tank. It should be mentioned in passing that additional plasters and slurries applied on the earth-facing side can also perform the waterproofing function. However, this method is hardly widespread or is used as a supplement to the White Tank.

Another well-known, but forgotten and now rediscovered form of waterproofing is the bentonite waterproofing. This is a surface waterproofing where the components in contact with moisture such as walls and floors are wrapped on the earth-facing side in bentonite mats. Bentonite is a naturally occurring, highly swelling clay that already exhibits a strong waterproofing effect against water even in thin layers. Due to its brown color, this form of waterproofing is accordingly called the Brown Tank.

While in the USA buildings have been protected from groundwater ingress using bentonite for many years, this material is so far mainly used in landfill construction in our country. Only through the idea to produce and lay bentonite in sheets does this material gain importance again for building waterproofing. This product is made by pre-hydrating (pre-moistening) the bentonite. Through the patented process, an extremely highly sealing, plastic bentonite clay is produced. The building material has, in addition to a very high swelling capacity, very good mechanical resistance. The sealing effect remains even under repeated frost, thaw, and dry/wet cycles. It is resistant to chemical attacks and biologically non-degradable.

Source: my homepage

Our builder initially assumed a black tank and gave us an offer for the interior plastering of the cellar. This amounts to just under 3000,-. Is it the same price or cheaper with a concrete cellar?

You should not consider building a different cellar than the one recommended in the soil report. There is a reason for that, and you certainly want dry rooms, too, right?

Why should plastering on concrete walls be more expensive/cheaper than on masonry? The work is the same

Regards from the Rhineland

Actually, I wanted to avoid the discussion about the construction of the basement.
To clarify once again.
The soil survey recommends at least a masonry basement with improved waterproofing, so probably a fabric-reinforced bitumen layer. I thought that meant a black tank, which it apparently is not.
However, in the neighborhood, concrete basements have increasingly been built. We are currently considering that. It is just much more expensive in terms of price.

What I care about, however, is the interior plaster.

Therefore, the question again:

Is interior plastering in a concrete basement simpler and more cost-effective than in a masonry basement, or does it not matter?

Just get a quote for both types of basements, then you'll know. I think it's hard to say that in such general terms.

So once again the question:

Is an interior plaster in a concrete cellar easier and cheaper than in a masonry cellar, or does it not make a difference?

Since we will have both concrete walls and "regular" masonry walls in our house, I can tell you that the difference lies only in a primer for concrete walls = about 50 cents to one euro per sqm = negligible. That’s how we received the quotes from plasterers.

Hello,

....The soil survey recommends at least a masonry cellar with improved sealing, probably a fabric-reinforced bitumen layer....

Your planner will have to assume liability for the "water tightness," after all, that is what he gets paid for!
The interior plaster has at best an optical effect. Certainly appropriate for residential use of the cellar, but for secondary use, any additional plaster is certainly dispensable

...I thought a "black tank" was meant, which apparently it is not....

What one thinks personally usually contradicts offers, contractual relationships

Best regards