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What type of paint should I use on wood fibre internal wall insulation systems?

4 Posts
3 Users
Posts: 80
Member Admin
Topic starter
Any paint finishes that are applied to the lime plasters should be classed as breathable. This is usually a pretty vague description but I would suggest that any clay, lime or silicate paints would be plenty vapour permeable enough. Additionally, products such as acrylic supermatt are fine but do not use any vinyl based paint. A single coat would not be a problem but successive coats would begin to reduce the permeability of the surface too much, particularly on insulation covering brickwork or porous stonework.
Companies such as Keim and Baumit do nice silicate paints (although Baumit are more set up for commercial users rather than domestic as the smallest tub they do is 5 litres). Earthborn do nice clay paints but equally there are many other suppliers out there that have a good offering.
Hope that helps.
Posted : 09/02/2021 5:36 pm
Vickie Ward
Posts: 1

I used a natural paint from AURO and it is beautiful to use and apply - can stop painting a wall and go back the next day and there are no 'overlap' marks, it joins up beautifully.

There is a distributor who does their own range of colours using Auro as its base, which includes 40% and 60% colours.


Photos of the paint on my house here:

Posted : 10/03/2021 9:45 am
Posts: 1

Hello Chris,
Do you have experience with Climate Coating paints for internal applications (ThermoPlus, ThermoVital)? They claim the paint is breathable and capillary active and, thus, can even regulate room humidity. If its declared properties were valid, it would make a great addition to the internal insulation.

Posted : 24/04/2023 11:38 am
Posts: 80
Member Admin
Topic starter

Thanks for your comment @heike 

Whilst I don't know the paints specifically, there is very little impact that a coating so thin is going to have over the surface of the wood fibre systems, which are already vapour permeable and extremely capillary active. I suspect you'd get a noticeable benefit on uninsulated masonry but I'm not sure you'd perceive any benefit over the plastered wood fibre.

Hope that helps.

Posted : 24/04/2023 1:52 pm
Heike reacted

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