Hi, I'm a DIY plasterer with some experience doing float & set, skimming with usual plasters but not sand/cement/lime rendering. If the answers are already out there on this forum, please accept my apologies in advance but I have done a search to no avail.
1) Chimney breast. I don't want to dot 'n' dab plasterboard and would rather float and set as the rest of the room. The chimney breast plaster was previously hacked off (inc. sides), to accommodate a wood burner - soon to be fixed. The background has been PVAd, so for the scratch coat I intend to use Bonding. However, I've never used Hardwall (only Browning) before and would like to have a go.
Q1) Do you think I could safely use Hardwall final float coat on a Bonding scratch coat or just go Bonding all the way?
2) Beading for arch. Obviously for the chimney breast sides, the usual angle beading is no problem, but the arch is proving a headache. I could buy a pair of arch formers and marry these up to the vertical bottoms of the arch with some normal angle bead but being metal, I've read that the expansion and contraction due to heat variations might cause the plaster (breast side) and render arch inset sofit side to crack. So I then thought of the flexible plastic beading you can buy, but the stuff I've researched seems too narrow for float and set and would have to be built out somehow.
Q2) What would experienced plasterers suggest for beading around an arch where a wood burner is to eventually go?
3) Rendering of the internal arch and inset area. Okay, so as the scenario above suggests, I have to render the inside of the arch (including the curved bit above) with a lime s/c mix to account for the heat extremities of the wood burner (< 50 kW). I've never done a render coat before but would like to have a go. I've read on this forum and others that the lime will add flexibility and probably should go up on a 7:1:1 mix of sand:cement:lime.
Q3) Could people please advise whether the proportions above are correct?
Q4) Can people please recommend a suitable consistency, bearing in mind that I'd have to render the inside arch above the hearth to a square aperture for the fluepipe's register plate (the perimeter of which I intend to stop bead).
Q5) I'm unsure if the background to the arch inset area has been PVAd in places, so am wondering if s/c render will go over a low suction background and if not, should I apply PVA to the mix and background to ensure a firm footing?
Once again, thanks for any help in advance, regards Ian
1) Chimney breast. I don't want to dot 'n' dab plasterboard and would rather float and set as the rest of the room. The chimney breast plaster was previously hacked off (inc. sides), to accommodate a wood burner - soon to be fixed. The background has been PVAd, so for the scratch coat I intend to use Bonding. However, I've never used Hardwall (only Browning) before and would like to have a go.
Q1) Do you think I could safely use Hardwall final float coat on a Bonding scratch coat or just go Bonding all the way?
2) Beading for arch. Obviously for the chimney breast sides, the usual angle beading is no problem, but the arch is proving a headache. I could buy a pair of arch formers and marry these up to the vertical bottoms of the arch with some normal angle bead but being metal, I've read that the expansion and contraction due to heat variations might cause the plaster (breast side) and render arch inset sofit side to crack. So I then thought of the flexible plastic beading you can buy, but the stuff I've researched seems too narrow for float and set and would have to be built out somehow.
Q2) What would experienced plasterers suggest for beading around an arch where a wood burner is to eventually go?
3) Rendering of the internal arch and inset area. Okay, so as the scenario above suggests, I have to render the inside of the arch (including the curved bit above) with a lime s/c mix to account for the heat extremities of the wood burner (< 50 kW). I've never done a render coat before but would like to have a go. I've read on this forum and others that the lime will add flexibility and probably should go up on a 7:1:1 mix of sand:cement:lime.
Q3) Could people please advise whether the proportions above are correct?
Q4) Can people please recommend a suitable consistency, bearing in mind that I'd have to render the inside arch above the hearth to a square aperture for the fluepipe's register plate (the perimeter of which I intend to stop bead).
Q5) I'm unsure if the background to the arch inset area has been PVAd in places, so am wondering if s/c render will go over a low suction background and if not, should I apply PVA to the mix and background to ensure a firm footing?
Once again, thanks for any help in advance, regards Ian
