Rendering a Firplace, suitable for a woodburner.

[StartAtTheBegining]

Hi all, I'm new to this.

I have a plasterer coming in to do my living room & render my fireplace.

What mix is best to use, does 7:1:1 sound right? sand/cement/lime.
I have to level the back out before he comes on monday as there is a large crevice down the middle, so was going to get it started asap.

I've had a wire brush to the back & pva & water mix applied.

My plasterer has told me if I get it level he will apply the under coat and then come back and apply the finnishing coat.

Should I also add PVA to my mix

Any advice is welcome.

 

[StartAtTheBegining]

Another question what sand is best to use?
Rendering or Plastering, we want to paint on to the render so which ever gives the best finnish without cracking!

 

[Richard C]

I use 6:1:1 but 7:1:1 render will be fine; apply in two coats, initial scratch coat & float coat over that which should be slightly weaker than the initial scratch coat. You will never get sand/cement render to look like finish plaster but ONLY use heat proof plaster (Vitcas) in the area 800mm above & 300mm either side of the stove; Gypsum plaster base coat, finish or boards won’t stand more than 49 degrees & will fail. This topic comes up so often now, I’ve put together this list of links; you will probably find all the info you need in there but not all may be relevant to you but come back if you need more info.

You can DIY but you need to know the Building Regs (which changed in October), submit a Building Notice & pay a fee. Your LABC will inspect &, assuming everything is OK, issue a compliance certificate; the BI may want to witness smoke & spillage tests.

Lots of archive threads on this, & other things you have to watch out for, here a few links for you to read:
http://www.stovesonline.co.uk/stove_building_regulations.html
http://www.hetas.co.uk/public/certificates.html
http://www.solidfuel.co.uk/pdfs/buidling_regs_consumer leaflet.pdf
//www.diynot.com/forums/viewtopic.php?t=183614
//www.diynot.com/forums/viewtopic.php?t=211524
//www.diynot.com/forums/viewtopic.php?t=242738
//www.diynot.com/forums/viewtopic.php?t=224751

& some more sobering just in case you think it’s all a load of old tosh:
http://www.solidfuel.co.uk/main_pages/news.htm
http://www.dailymail.co.uk/news/art...wood-burning-stove-leaks-carbon-monoxide.html

Also get at least 3 quotes from local independent HETAS installers:
http://www.hetas.co.uk/nearest_member

You might be pleasantly surprised if you get quotes from independent HETAS installers (stove shops will generally charge you a fortune) & you should ask yourself if you really want all the hassle & risk getting it wrong; climbing onto the roof with an 8M stainless steel snake on your back is not for the feint hearted!

 

[Richard C]

Just noticed a couple of bits I didn’t answer; I have used PVA under render in the past but was told by another spread with far more experience than me that it wasn’t a good idea. I now just give everything a good dousing with water, twice & then let it dry off for a ½ hour. Some use PVA in internal render (never mix it with external render, use SBR) but I don’t. It will act as a plasticiser but you don’t really need it with a sand/cement/lime mix as the lime has the same effect.

What’s “a large crevice”? If you’ve got cracks in the blocks/bricks you will need to carry out remedial work & steel lath reinforcement before rendering; render on its own wont hold it together & it’ll just crack again.