Hi all

I have a freestanding wood stove in a room corner. The walls are solid, plastered. Cement board was fitted to the two walls to prevent the plaster from cracking and has performed well, but it has come unstuck. The installer fixed it with dot and dab blobs of what I think was CT1.

So I'm looking to refix them and wondered what's best?

• Cement board screws (or would other types of screws work, and if so what's best)?

• Some type of appropriate no nails type adhesive?

• Fire cement? Plasterboard adhesive?

• Or a combination of some of these?

Would much appreciate any thoughts and advice.

Many thanks

Is an air gap required?

I put skamotec boards up around and over our's stuck and fixed to the wall with some vitcas adhesive, then a number of hammer in fixings per board. It was tiled over, rather than plastered though.

CT1 dabs on their own are the weak point here. The board heats and cools every time the stove runs, so a few blobs end up taking all the movement and eventually let go. I'd refix it mechanically and use the adhesive as backup rather than the main fixing.

Check the plaster behind first. If any of it has blown or sounds hollow when tapped, cut that back, because the fixings need to pull the board tight to something solid.

Then I'd back butter the board with a heat resistant tile adhesive (Vitcas do one, or a decent flexible cementitious adhesive) using a notched trowel so you get near full contact rather than dabs. Drill through board and plaster into the masonry and fix with masonry screws or hammer in fixings with a washer head, roughly 300mm centres and 50mm in from the edges, countersinking slightly so the heads sit flush.

I wouldn't use fire cement, it's brittle and meant for sealing joints, and gypsum based plasterboard adhesive isn't ideal that close to the stove either.

On the air gap, if the wall is solid masonry it's non combustible anyway, so the board is really just protecting the plaster finish. Still worth checking the clearances in your stove manual. Finish with tiles in heat resistant adhesive and grout, or a skim, and leave a small gap at the corner and edges for movement.