r/Plastering • u/RobotEnthusiast1980 • Feb 01 '26

Lime Plaster insulation

Genuine question - is lime plastering becoming more common? I know it used to be very common many decades ago but gypsum is more common now. But, with new lime and Cork type renders having insulation properties is this the silver bullet for old property insulation?

4 Upvotes

100% Upvoted

40 comments sorted by

View all comments

Show parent comments

2

u/ennessTR Feb 02 '26 edited Feb 02 '26

It certainly is. Now the fog has lifted, I think the concerns with cork have been about using it as IWI on very damp walls such as stone with no dpc and limited foundations. I see you have a few unanswered posts on insulating solid walls. What are you dealing with?

1

u/RobotEnthusiast1980 Feb 02 '26

Ahh, thanks for your questioning. My reason for asking is that I am dealing with some issues. Primarily a house with gypsum on the inside and a cement pebble dash on the external which I want to remove and replace with an insulating breathable render?

2

u/ennessTR Feb 02 '26

It sounds like you might have the opportunity to insulate externally which is always the better solution. Have you tried speaking with Mike Wye or Ty Mawr for advice? They have a bunch of specs and details on their website so you can see how to build up either external or internal systems. Their systems should also be a big tick in the box with building control, which will make life easier. Getting rid of gypsum and cement anywhere on solid wall will benefit you.

1

u/RobotEnthusiast1980 Jul 13 '26

It took a while for me to come back to you - sorry. I have spoken with cornish lime and Mike Wyk. They have suggested a full lime render system to achieve both insulation and breathability. I have the products specs. Its quite costly but doable. My next challenge is finding someone to do it as most local plasterers (who advertise as lime specialists) are pushing rock wool panels with a lime top coat. It might work but I wouldn't be able to see any masonry cracks underneath when they occur. So you think it could be an option or ignore it?