Rendering the back of a fireplace

[nephilim]

We are about to put into our fireplace a free standing woodburner but before that I would like to tidy up the back of it to hide the occasional repair and also where the existing render has come away. I was thinking to applying a thin render/skim over the whole rear of the fireplace with somekind of lime mortar mix. I want a creamy finish to it. Just wondered what the mix would be, would it be just like cement, maybe a 3-1 sand/lime mix, would it stick well to the back of the soot covered wall? Any ideas or comments welcome. Also, would I apply it using some kind of plasterer's trowel/float?

[jondeau]

I doubt very much that a thin layer of mortar will stick for very long to a soot covered wall.

How about using a board of some kind to cover up the back of the fireplace...maybe even plasterboard would do, then you can paint it whatever colour you like.

[Jonzjob]

How hot is it going to get? What is the distance between the back of the burner and the wall? If it's too close any paint that isn't a specialised paint will scorch at least...

[Patf]

If you do use board there is a special fire-resistant type. Leroy Merlin sell it.

Husband covered ours with imitation brick facing.

[Eos]

We too used the special fire proof plaster board, skimmed and then painted.

Jotul specified distances from all surfaces were used and indeed exceeded but I am a pyromaniac and while the paint has not discoloured, the plaster has cracked!

[BIG MAC]

Without knowing what the fireplace /chimney is made of it's difficult to comment however there's another couple of possibles....

1) Expanded metal lath afixed to inside of chimney then rendered to provide a smooth surface

2) Brick slips (Slices of brick fastened with adhesive similar to ceramic tiling but giving the appearance of brick)

Hope this helps

 

[Dave&Olive]

hi OK

   the soot will always burn through in time ...... however there is a remedy but not a cure ... bit messy .. you need to find very fresh cow dung greener the better mix to a runny paste with water and paste onto the wall ,when dry cover with lime wash .

 Dave

[Jo]

Won't that whiff a bit when it warms up?[blink]

[nephilim]

Thanks for all your thoughts on the fireplace, I actually did it yesterday, had to sort something out quick as the fire is due to be installed tomorrow. Hopefully the first poster is wrong but I ended up applying a lime based mortar (a couple of centimeters thick) to cover the whole area at the back. It has come up ok and covered the mess that was there. It is not that smooth, but I wanted the rustic look, well that is my excuse. Just waiting for it to all fall off now!