What Is Efflorescence? How to Remove It? How To Prevent It?

What Is Efflorescence? How to Remove It? How To Prevent It?

[markrowland]

I have to confess that I had never heard of Coo-Var. Very interesting video, thanks. Clever stuff.

[ChrisGamble]

Surely using steel wire is a no-no with salt presence. Anti Alkaline Primer isn't going to be effective if efflorescence is still occuring behind it. First need to neutralize the salts with muriatic acid like lemon juice or distilled vinegar until it stops fizzing. Then all this to evaporate as, quite correctly, washing off will only reactivate the salt crystalization. Brush down surfaces with a non-metal stiff brush. The Coovar will stick to the prepared surface. Occasionally there will be a show through which can repeat process. For any saturated plaster then best practice is to remove back to brick...then the above treated before replastering/rendering with a breathable waterproof additive. (PVA is water soluble so this will be counter productive on it's own). Once plaster has dried out fully a moisture meter...then repeat with. Coovar Anti Alkaline Primer BEFORE any finishing Vinyl Emulsion Coatings. After years of salt-water WC supply ingress repairs this is the most effective system l have found & proven. Any additional advice welcomed

[peteramond]

Good vid as always I decorated an old cottage about 4 months ago with lime plaster which had the same problem it had been plastered over in places with modern gypsum plaster causing it to blow and painted over lime with vynil Matt in places the walls were wet with damp it was an absolute nightmare I had to use alki primer then used McPhersons eclipse water permissible emulsion so the areas that were not sealed could breathe

[RebeccaEvans-wcks]

Do you use this primer before plastering? Or can you use it on top of dry plaster?

[hoochone]

Does the Alkali Resistant Primer allow the substrate to continue "breathing"...

[elizabethdarlow]

Does the alkali primer mean you don't need to use a salt neutraliser?

[boneonn]

Would this stop salt coming back through

[DurangoRT]

If you don't seal it from the outside the efflorescence will just come back.