Renew base coat plaster on an old barn

Hello everyone,

in the course of building the terrace, I would like to redo the base of an old stable.
Many years ago, the area was leveled up a bit and the soil was just dumped against the building with [Noppenbahn].
An excavator was there and dug out down to the strip foundation.
Now a drip edge strip is being made.
Before that, I want to remove the paint and loose plaster from the base because it is already coming off.
How exactly should I proceed here and which materials would you use?
Priming, slurry waterproofing, plastering, [Noppenbahn]...
I am grateful for any help.

Best regards, Tom

Hi Tom,

looks like you have already done good preliminary work with the excavation – now you can really make something out of it.

As for the base, I would proceed as follows:
First, thoroughly remove all loose material, such as old plaster, paint, crumbly substrate – preferably with a spatula, wire brush, and possibly a small rotary hammer with a plaster milling cutter. Then sweep thoroughly and prime with a deep primer or bonding primer for mineral substrates.

Next comes the waterproof slurry – depending on the product, applied in 2–3 layers, crosswise. Be especially careful at transitions and edges. This is absolutely advisable in the splash water area.

Then you can plaster neatly with base plaster (e.g. cement or lime-cement plaster). If you want it especially robust, base plaster with reinforcement or additional fabric embedding is also possible.

If you want to install a studded membrane again: leave a gap to the wall (approx. 1 cm), studs towards the wall, and finish neatly at the top with a closing profile – then no moisture will accumulate behind the membrane.

Good luck – looks like a nice project!

Thank you in advance for your reply. Since I hadn’t received any answers so far, I took matters into my own hands. I removed all loose material and paint with a grinder. Then I replastered with cement plaster and mesh. However, I didn’t use any sealing slurry but would apply bitumen coating in the earth-contact area (simply because I already bought it). One more question about the studded membrane. I have a studded membrane with fleece. Would you not recommend that? As far as I know, the fleece (which is attached to the studs) should face the soil, correct?

Thanks in advance and best regards, Tom