I have cut into some retaining walls made of concrete. The walls are currently plastered with a thin layer, say ~10mm. The plaster is ridiculously hard, indicating a very high cement content. I estimate the sand size to be 0-2mm. Now I need to plaster the surfaces where I have cut and wonder what type of mortar I should use and any potential preliminary work?
I've searched through some old threads and there are many suggestions. I've also called Weber's customer support (which I find usually very competent) and got a hold of a guy who couldn't provide straight answers either.
I've previously repaired smaller plaster areas on the house's base with cement mortar A since that plaster is also very hard (similar to the one on the concrete walls). Those plasterings turned out well but there were very large and ugly color shifts between the old and new plaster.
What are your suggestions?
I've searched through some old threads and there are many suggestions. I've also called Weber's customer support (which I find usually very competent) and got a hold of a guy who couldn't provide straight answers either.
I've previously repaired smaller plaster areas on the house's base with cement mortar A since that plaster is also very hard (similar to the one on the concrete walls). Those plasterings turned out well but there were very large and ugly color shifts between the old and new plaster.
What are your suggestions?
Seems like it is plastered with A bruk so the best is to continue with the same type of bruk that you already have.
There tend to be adhesion issues if the concrete is very smooth, so it's common to apply a red primer and netting. But since it's about repairs in your case, use Cementbruk A (Weber's has a 0-2 mm fraction, others 0-3).
The color variations are often due to the sand in the mortar coming from different places. To counteract this, you can thin plaster everything (apply with a steel trowel and spread out) with 0-1mm B-mortar (Weber 133 plaster mortar b hand). If you choose to do this, you can also make the repairs with the same mortar.
The color variations are often due to the sand in the mortar coming from different places. To counteract this, you can thin plaster everything (apply with a steel trowel and spread out) with 0-1mm B-mortar (Weber 133 plaster mortar b hand). If you choose to do this, you can also make the repairs with the same mortar.
A Cementbruk A you can do everything with except put it on your sandwich for the most part, works for almost anything..
Combimix C bruk is great stuff to finish with, very small aggregate.
Combimix C bruk is great stuff to finish with, very small aggregate.