Hearth

[PerpetualLeakingRoof]

Hi,

I'm about to start fitting our decorative hearth but I was wondering about how to best go about it.

I've fitted a constructional hearth (at least 6" thick) and made sure the top is fairly level and at joist height. I realize now the constructional hearth should be level with the top of the floorboards but the decorative hearth is 50mm thick so once it's in place the top of the hearth will be heigher than the floor.

Since the hearth stone is very heavy (big front piece, two smaller back pieces) I was thinking an easy way to fit it might be to pour leveling compound in to the recess I still have for the constructional hearth and just slide the hearth stone in on top once it's set. Optionally I could put a very thin bed of mortar between the leveling compound finish and the hearth stone to take out any final bumps.

What do you think? Would I be better to just put in a good thick bed of mortar?

 

[noseall]

What do you think? Would I be better to just put in a good thick bed of mortar?

I can't think of a better/simpler way.

 

[PerpetualLeakingRoof]

Thanks, I'm still tempted to stick some levelling compound in there but one thing I've learnt is 99.9999% of the time the professionals already do a job the easiest way it can be done so mortar bed it is

Got a follow up question though...

Our plaster got a bit carried away while doing the living room and has plastered inside the fireplace. We are going to be fitting a wood burning stove in there and I'm a little concerned about the plaster cracking behind the stove where it will be almost impossible to fix. Would be be best to just tile in there now before the stove is fitted? If so are there any particular requirements for the tiling such as special tile cement or a certain thickness of tile? I was thinking of maybe using stone floor tiles.

 

[Richard C]

Gypsum plaster (base & finish coats) is specified up to a max. temperature of 49 C. unless he’s used a specialist heat proof plaster (which seems unlikely) it will in all probability crack, blow & fall of in a very short time. Tiling over it will provide very little protection as the heat will still permeate through the tiles into the plaster behind & then the whole lot will fall off! I would sort it out now while you still have easy access.

 

[squarepeg]

Thanks. OK, so our next step is obviously to take the plaster off. Once we've done that there are two questions: firstly, what should we use to cover the brickwork? and secondly, is it possible to do it ourselves? In this regard, it may be useful to know that if it were gypsum, we would be happy to do so, but other materials may require a bit more skill! Essentially, the stove is due to be fitted in a couple of weeks, and as the area is only approx 2 square m's we will likely struggle to get anyone to do it.

 

[stuart45]

Use a lime render, as this will cope with the heat.

 

[Richard C]

This is supposedly the proper stuff;
http://shop.vitcas.com/vitcas-heat-resistant-plaster-16-p.asp

I used a lime sand/cement/lime render mix on mine as Stuart 45 suggests. It rather depends on what sort of finish your after; if render is sufficient or if you want a smooth plaster finish. You could always tile directly over the render base & a cement powder adhesive should withstand the heat pretty well, again it's what I used to fabricate a black granite surround. The plaster is no more difficult to use than conventional plaster but lime render can be a bit of a challenge for the inexperienced; I suspect the Victas screed is much the same but have not tried it.