Which plaster for interior basement wall in Leca?

[Prosit]

I was thinking of trying to apply some plaster on the inside of our basement walls which are made of Leca blocks. The walls are uninsulated, if that matters.

From what I understand, most types of plaster work on Leca, but can someone recommend something that has a good chance of turning out well?

I want as smooth a surface as possible.

 

[wickerman]

If there is no plaster where you should apply a serpo 103 red primer first. Then use an a or b mortar type serpo 222... lastly, apply a c mortar... serpo 133 and make the surface fine.

The mortars are divided into abc classes where a mortar weighs the most and c the least. If you apply a c mortar at the bottom and then a b mortar on top of this, it will come off within a couple of years.

 

[Prosit]

OK, thanks.

If I can now imagine not having it so smooth and fine - is it then sufficient with just rödgrund and then painting over it with silicate paint?

 

[Prosit]

My basement walls are currently not insulated from the outside, but will likely be in the future when I redo the drainage. I'm considering Isodrän or something similar.

The question then is, should I go for cement-based plaster (which I believe the aforementioned are?) or gypsum plaster?

 

[Prosit]

I have read some instructions that say you should put mesh in the first layer after the scratch coat, is it a good idea or overkill?

In that case, what type of mesh? Stainless steel? Fiberglass?

 

[anaitis]

My basement walls are currently not insulated from the outside but will likely be in the future when I redo the drainage. I'm thinking about Isodrän or something similar.

The question is, should I go for cement-based mortar (which I suppose the aforementioned are?) or gypsum plaster?

Not gypsum on basement exterior walls.

 

[anaitis]

I have read some instructions that say you should set mesh in the first layer after the red base, is it a good idea or overkill?

If so, what type of mesh? Stainless steel? Fiberglass?

Probably overkill.
Otherwise, the most common is galvanized mesh for "real" plaster and fiberglass for "plastic plaster".

 

[Prosit]

Is it OK to apply B-mortar directly on Leca? From what I can see, it seems to be mostly outdoors where you need red primer...

...or maybe C-mortar directly on the Leca?

There are some small holes/irregularities that need to be filled, are the above mortars sufficient for that as well?

 

[källare]

I've replastered my recreation room, where the walls consist of leca and concrete blocks. I knocked down all existing plaster and cleaned it with a wire brush and vacuum cleaner. Then I brushed on primer and set up guide strips and galvanized plaster mesh. The next day, I plastered with C-mortar, Serpo 244. After a month, the walls were painted with silicate paint. I'm very satisfied with the result.

I am now preparing to replaster two other rooms in the basement. Since these will be tiled, I'm using primer, plaster mesh, and B-mortar, Serpo 222 this time.

I can recommend using plaster mesh, as it protects against future cracking and increases durability. It's also easier to apply plaster with the mesh than without. There’s a bit of work involved in setting up the mesh, but it's worth it.

Yes, you repair the holes with the same mortar you use for plastering.