Second coat of multi finish weak and poorly adhered to 1st coat

RJW91

New Member
Afternoon everybody, just after a bit of insight as to why I’m having this problem.

So, I recently re-skimmed my spare bedroom, it’s almost all dry now, just a few damp patches here and there.

I wanted to get the new electric radiator all fitted so that after painting I can just re-fix the brackets and connect everything back up and not potentially scratch the paintwork or leave pencil marks.

I drilled my first hole for the brackets and the skim coat around it blew and cracked apart. The immediate area around it can also be hacked off fairly easily with just a filling knife and a bit of elbow grease.

This wall was the last surface in the room to be skimmed and although as I said there were some damp patches, the spots where I had to drill for the brackets were all dry.

I decided to drill another hole in the first wall I skimmed, which had no damp patches at all. The wall with the brackets is also an external wall and I thought that maybe it was still a bit damp below the surface and with the cold and wet weather maybe that just needed to dry out a bit still.

But no, same problem on the other wall which is only a partition! Please see the attached pictures.

A bit of background info:

the walls are 3” block internally, 2” cavity filled with some white insulation foam and then a single skin brick wall externally. I believe the house was built in the early 70s and the blocks almost look as though they have small pieces of wood fiber in them. Not as soft as a modern thermalite but easy enough to drill through without a SDS on hammer drill.

The walls were rendered with what looks like a somewhat coarse mix, quite a few big chips of stone and chalk in there.

They were them skimmed with a gypsum finishing plaster. When I first moved in it became clear early on that this would be a problem for me, as again it was very poorly adhered in places and could be scraped off without much effort at all. It wasn’t that bad everywhere, but as I had no way of telling where it would be like this I decided to hack it all off and re-skim everything.

So I initially coated the walls with a mix of 1/3 watered down PVA. This was really just to keep the dust at bay while I got on with other things like door linings and window boards.

When it came time to start skimming, I took the advice of a Youtube plasterer and coated them in neat PVA. I let it all dry completely and I figured this would be okay as the PVA would re-emulsify when wet and stick quite well to the old render that was still fairly porous after the initial 1/3 coat of PVA. Some areas I had also blue gritted, as I had parts of the render to patch up with bonding and after letting them dry. I gave them another coat of blue grit and then a coat of neat PVA, as I felt this would rough them up a bit and be a similar match in terms of suction (or lack thereof) to the rest of the walls that has 1/3 PVA and then neat.

So again, all the PVA and blue grit had dried, gave everything 2 coats of multi finish and it all went on okay, no problems there. Again, everything seemed perfectly okay when drying, it wasn’t until I drilled a hole in the wall that I noticed this problem.

I’m trying to think why this has happened, the theories I can come up with so far are:

The neat PVA/blue grit have formed a film, as expected and drilling into the wall is de-laminating this and also the skim. The only problem with this is the 1st coat of skim isn’t going anywhere and as I had hoped is stuck to the old render really well.

Another idea is that, because the walls were very well sealed up, the 1st coat couldn’t dry out without pushing against the second coat, causing it to adhere poorly.

As mentioned previously, with the weather being the way it is at the moment I have thought that maybe that has in some way contributed? I’m renovating the house quite a bit and for heating at the moment I’ve just got a few plug in electric radiators. It hasn’t felt freezing inside, but again not much in the way of heating. I have done all the mixing in this old lean to thing outside, not fully outdoors but near enough and at times the weather was almost freezing, if not actually freezing. I used water from the storage tank in the loft for mixing as I thought using the outside tap would be colder and possibly more problematic. The tank in the loft and all the pipework aren’t even a year old so no chance of contamination. They’re all well insulated as well so it was the warmest (without being actually warm) source of water I had available. Having said all that, unless I’m missing something I still can’t understand why this has only happened to the second coat.

Maybe I’m just expecting too much from multi finish? It’s not as if it’s cracking or blowing anywhere and it doesn’t exactly come off without a little persuasion. But still, all it takes is one hole to be drilled and the immediate 3/4” diameter around it will crack and blow, is that normal for fresh multi finish?

Haven’t tried rolling paint on it yet and I’m a little apprehensive about doing anymore until I can figure out why this is happening.

Even where I’ve cut back some of the excess plaster from around the socketback boxes, no blowing or cracking around there.

If any of you actual plasterers can advise me on this matter I would be most appreciative. I haven’t checked if the ceiling has the same problem just yet, that was blue grit and neat PVA over old paint and then 2 coats of multi. Would that be worth checking to see if it’s havthe same problem?

On a side note, does anyone know how thin foam adhesive can set and still successfully hold plasterboard to a block wall? I ask as I’m contemplating doing this and just taping/jointing everywhere instead. I’m very much a complete amateur plasterer and although I’m happy enough with the finish I can achieve I would rather do that than carry on like this if I’m going to have to put up with this kind of a ballache everytime I try and skim!

It’s frustrating, because as I said I’ve already fitted new door linings and I fitted these so that they would be as wide as the existing walls and render, plus a little extra for a new skim coat to finish flush with them both sides.

This amounts to around 1/2” - 3/4” between the blockwork and the face of the door linings, which could make dot and dab, batten&board or foam adhesive difficult to use without bringing the plasterboard proud of the door linings.

Anyway, you have my thanks if you’ve read all this way and again, any advice on these matters I would be very appreciative of. Thanks!

*Edit:

Just tried the ceiling, same 8mm masonry drill used in the same
combi drill, not on hammer, same as the walls. Not had the same problem there although in fairness I only attempted this in one spot.

If it makes any difference, I gave the ceiling a coat of bonding before 2 coats of multi finish because it’s very wavy. Otherwise it was prepped practically the same as the walls. One coat of blue grit and one coat of neat PVA.
 

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Last edited:

RJW91

New Member
Plastering not as easy as it looks is it
If I watch snooker on tv I don’t expect to be able to do a 147 break, neither if I watch Bruce Lee do I expect to put any man down in 2 seconds.
Plastering - people think you slap on PVA and your all set?
Neat PVA is for woodwork
It sure isn’t easy. I don’t expect to watch a few YT videos and be an expert, but it’s something I enjoy for some reason and I’m happy to give these things a go, learn through my many, many mistakes and deal with the inevitable consequences of them.

Do you think it is the neat PVA that’s the problem then? As I said the 1st coat isn’t going anywhere, solid as a rock. The second coat though, it’s hardly adhered at all.

It’s just like the original skim coat really, comes off effortlessly. Although as far as I can tell there was only ever 1 coat of the original finish plaster.

Is it also possible that although it all appears dry it actually isn’t and maybe that’s the problem?
 

tapit

Well-Known Member
Afternoon everybody, just after a bit of insight as to why I’m having this problem.

So, I recently re-skimmed my spare bedroom, it’s almost all dry now, just a few damp patches here and there.

I wanted to get the new electric radiator all fitted so that after painting I can just re-fix the brackets and connect everything back up and not potentially scratch the paintwork or leave pencil marks.

I drilled my first hole for the brackets and the skim coat around it blew and cracked apart. The immediate area around it can also be hacked off fairly easily with just a filling knife and a bit of elbow grease.

This wall was the last surface in the room to be skimmed and although as I said there were some damp patches, the spots where I had to drill for the brackets were all dry.

I decided to drill another hole in the first wall I skimmed, which had no damp patches at all. The wall with the brackets is also an external wall and I thought that maybe it was still a bit damp below the surface and with the cold and wet weather maybe that just needed to dry out a bit still.

But no, same problem on the other wall which is only a partition! Please see the attached pictures.

A bit of background info:

the walls are 3” block internally, 2” cavity filled with some white insulation foam and then a single skin brick wall externally. I believe the house was built in the early 70s and the blocks almost look as though they have small pieces of wood fiber in them. Not as soft as a modern thermalite but easy enough to drill through without a SDS on hammer drill.

The walls were rendered with what looks like a somewhat coarse mix, quite a few big chips of stone and chalk in there.

They were them skimmed with a gypsum finishing plaster. When I first moved in it became clear early on that this would be a problem for me, as again it was very poorly adhered in places and could be scraped off without much effort at all. It wasn’t that bad everywhere, but as I had no way of telling where it would be like this I decided to hack it all off and re-skim everything.

So I initially coated the walls with a mix of 1/3 watered down PVA. This was really just to keep the dust at bay while I got on with other things like door linings and window boards.

When it came time to start skimming, I took the advice of a Youtube plasterer and coated them in neat PVA. I let it all dry completely and I figured this would be okay as the PVA would re-emulsify when wet and stick quite well to the old render that was still fairly porous after the initial 1/3 coat of PVA. Some areas I had also blue gritted, as I had parts of the render to patch up with bonding and after letting them dry. I gave them another coat of blue grit and then a coat of neat PVA, as I felt this would rough them up a bit and be a similar match in terms of suction (or lack thereof) to the rest of the walls that has 1/3 PVA and then neat.

So again, all the PVA and blue grit had dried, gave everything 2 coats of multi finish and it all went on okay, no problems there. Again, everything seemed perfectly okay when drying, it wasn’t until I drilled a hole in the wall that I noticed this problem.

I’m trying to think why this has happened, the theories I can come up with so far are:

The neat PVA/blue grit have formed a film, as expected and drilling into the wall is de-laminating this and also the skim. The only problem with this is the 1st coat of skim isn’t going anywhere and as I had hoped is stuck to the old render really well.

Another idea is that, because the walls were very well sealed up, the 1st coat couldn’t dry out without pushing against the second coat, causing it to adhere poorly.

As mentioned previously, with the weather being the way it is at the moment I have thought that maybe that has in some way contributed? I’m renovating the house quite a bit and for heating at the moment I’ve just got a few plug in electric radiators. It hasn’t felt freezing inside, but again not much in the way of heating. I have done all the mixing in this old lean to thing outside, not fully outdoors but near enough and at times the weather was almost freezing, if not actually freezing. I used water from the storage tank in the loft for mixing as I thought using the outside tap would be colder and possibly more problematic. The tank in the loft and all the pipework aren’t even a year old so no chance of contamination. They’re all well insulated as well so it was the warmest (without being actually warm) source of water I had available. Having said all that, unless I’m missing something I still can’t understand why this has only happened to the second coat.

Maybe I’m just expecting too much from multi finish? It’s not as if it’s cracking or blowing anywhere and it doesn’t exactly come off without a little persuasion. But still, all it takes is one hole to be drilled and the immediate 3/4” diameter around it will crack and blow, is that normal for fresh multi finish?

Haven’t tried rolling paint on it yet and I’m a little apprehensive about doing anymore until I can figure out why this is happening.

Even where I’ve cut back some of the excess plaster from around the socketback boxes, no blowing or cracking around there.

If any of you actual plasterers can advise me on this matter I would be most appreciative. I haven’t checked if the ceiling has the same problem just yet, that was blue grit and neat PVA over old paint and then 2 coats of multi. Would that be worth checking to see if it’s havthe same problem?

On a side note, does anyone know how thin foam adhesive can set and still successfully hold plasterboard to a block wall? I ask as I’m contemplating doing this and just taping/jointing everywhere instead. I’m very much a complete amateur plasterer and although I’m happy enough with the finish I can achieve I would rather do that than carry on like this if I’m going to have to put up with this kind of a ballache everytime I try and skim!

It’s frustrating, because as I said I’ve already fitted new door linings and I fitted these so that they would be as wide as the existing walls and render, plus a little extra for a new skim coat to finish flush with them both sides.

This amounts to around 1/2” - 3/4” between the blockwork and the face of the door linings, which could make dot and dab, batten&board or foam adhesive difficult to use without bringing the plasterboard proud of the door linings.

Anyway, you have my thanks if you’ve read all this way and again, any advice on these matters I would be very appreciative of. Thanks!

*Edit:

Just tried the ceiling, same 8mm masonry drill used in the same
combi drill, not on hammer, same as the walls. Not had the same problem there although in fairness I only attempted this in one spot.

If it makes any difference, I gave the ceiling a coat of bonding before 2 coats of multi finish because it’s very wavy. Otherwise it was prepped practically the same as the walls. One coat of blue grit and one coat of neat PVA.
Say again mate?
 

RJW91

New Member
Say again mate?

I did some skimming recently. The second coat doesn’t seem to have adhered well to the 1st which I first noticed after drilling a hole in the wall and the new plaster around it blowing and scraping off without much effort.

Any ideas why this might have happened?
 

bobski

Well-Known Member
Plastering not as easy as it looks is it
If I watch snooker on tv I don’t expect to be able to do a 147 break, neither if I watch Bruce Lee do I expect to put any man down in 2 seconds.
Plastering - people think you slap on PVA and your all set?
Neat PVA is for woodwork


I disagree with 1 of them.

 

Vincey

Private Member
Omg pva is to be diluted down it says it on the back of the tub, just read the tub it will tell you
I’m similar to the others haven’t a clue what is going on at this job but I do know plastering should never be this hard mate if it’s this hard sometimes it’s best to admit this maybe isn’t the right thing for you
 

Monkey Boy

Well-Known Member
I said the 1st coat isn’t going anywhere, solid as a rock. The second coat though, it’s hardly adhered at all.
Are you sure just the second coat is coming away? Not rather all your multi both coats are coming away?
Whatever you put on the wall before the multi I don’t think would cause a fail between the two coats? You don’t just place it on the wall but work it in somewhat..
I’m just apprentice standard and know Jack squat anyway
 
Last edited:

themucky1

Well-Known Member
Afternoon everybody, just after a bit of insight as to why I’m having this problem.

So, I recently re-skimmed my spare bedroom, it’s almost all dry now, just a few damp patches here and there.

I wanted to get the new electric radiator all fitted so that after painting I can just re-fix the brackets and connect everything back up and not potentially scratch the paintwork or leave pencil marks.

I drilled my first hole for the brackets and the skim coat around it blew and cracked apart. The immediate area around it can also be hacked off fairly easily with just a filling knife and a bit of elbow grease.

This wall was the last surface in the room to be skimmed and although as I said there were some damp patches, the spots where I had to drill for the brackets were all dry.

I decided to drill another hole in the first wall I skimmed, which had no damp patches at all. The wall with the brackets is also an external wall and I thought that maybe it was still a bit damp below the surface and with the cold and wet weather maybe that just needed to dry out a bit still.

But no, same problem on the other wall which is only a partition! Please see the attached pictures.

A bit of background info:

the walls are 3” block internally, 2” cavity filled with some white insulation foam and then a single skin brick wall externally. I believe the house was built in the early 70s and the blocks almost look as though they have small pieces of wood fiber in them. Not as soft as a modern thermalite but easy enough to drill through without a SDS on hammer drill.

The walls were rendered with what looks like a somewhat coarse mix, quite a few big chips of stone and chalk in there.

They were them skimmed with a gypsum finishing plaster. When I first moved in it became clear early on that this would be a problem for me, as again it was very poorly adhered in places and could be scraped off without much effort at all. It wasn’t that bad everywhere, but as I had no way of telling where it would be like this I decided to hack it all off and re-skim everything.

So I initially coated the walls with a mix of 1/3 watered down PVA. This was really just to keep the dust at bay while I got on with other things like door linings and window boards.

When it came time to start skimming, I took the advice of a Youtube plasterer and coated them in neat PVA. I let it all dry completely and I figured this would be okay as the PVA would re-emulsify when wet and stick quite well to the old render that was still fairly porous after the initial 1/3 coat of PVA. Some areas I had also blue gritted, as I had parts of the render to patch up with bonding and after letting them dry. I gave them another coat of blue grit and then a coat of neat PVA, as I felt this would rough them up a bit and be a similar match in terms of suction (or lack thereof) to the rest of the walls that has 1/3 PVA and then neat.

So again, all the PVA and blue grit had dried, gave everything 2 coats of multi finish and it all went on okay, no problems there. Again, everything seemed perfectly okay when drying, it wasn’t until I drilled a hole in the wall that I noticed this problem.

I’m trying to think why this has happened, the theories I can come up with so far are:

The neat PVA/blue grit have formed a film, as expected and drilling into the wall is de-laminating this and also the skim. The only problem with this is the 1st coat of skim isn’t going anywhere and as I had hoped is stuck to the old render really well.

Another idea is that, because the walls were very well sealed up, the 1st coat couldn’t dry out without pushing against the second coat, causing it to adhere poorly.

As mentioned previously, with the weather being the way it is at the moment I have thought that maybe that has in some way contributed? I’m renovating the house quite a bit and for heating at the moment I’ve just got a few plug in electric radiators. It hasn’t felt freezing inside, but again not much in the way of heating. I have done all the mixing in this old lean to thing outside, not fully outdoors but near enough and at times the weather was almost freezing, if not actually freezing. I used water from the storage tank in the loft for mixing as I thought using the outside tap would be colder and possibly more problematic. The tank in the loft and all the pipework aren’t even a year old so no chance of contamination. They’re all well insulated as well so it was the warmest (without being actually warm) source of water I had available. Having said all that, unless I’m missing something I still can’t understand why this has only happened to the second coat.

Maybe I’m just expecting too much from multi finish? It’s not as if it’s cracking or blowing anywhere and it doesn’t exactly come off without a little persuasion. But still, all it takes is one hole to be drilled and the immediate 3/4” diameter around it will crack and blow, is that normal for fresh multi finish?

Haven’t tried rolling paint on it yet and I’m a little apprehensive about doing anymore until I can figure out why this is happening.

Even where I’ve cut back some of the excess plaster from around the socketback boxes, no blowing or cracking around there.

If any of you actual plasterers can advise me on this matter I would be most appreciative. I haven’t checked if the ceiling has the same problem just yet, that was blue grit and neat PVA over old paint and then 2 coats of multi. Would that be worth checking to see if it’s havthe same problem?

On a side note, does anyone know how thin foam adhesive can set and still successfully hold plasterboard to a block wall? I ask as I’m contemplating doing this and just taping/jointing everywhere instead. I’m very much a complete amateur plasterer and although I’m happy enough with the finish I can achieve I would rather do that than carry on like this if I’m going to have to put up with this kind of a ballache everytime I try and skim!

It’s frustrating, because as I said I’ve already fitted new door linings and I fitted these so that they would be as wide as the existing walls and render, plus a little extra for a new skim coat to finish flush with them both sides.

This amounts to around 1/2” - 3/4” between the blockwork and the face of the door linings, which could make dot and dab, batten&board or foam adhesive difficult to use without bringing the plasterboard proud of the door linings.

Anyway, you have my thanks if you’ve read all this way and again, any advice on these matters I would be very appreciative of. Thanks!

*Edit:

Just tried the ceiling, same 8mm masonry drill used in the same
combi drill, not on hammer, same as the walls. Not had the same problem there although in fairness I only attempted this in one spot.

If it makes any difference, I gave the ceiling a coat of bonding before 2 coats of multi finish because it’s very wavy. Otherwise it was prepped practically the same as the walls. One coat of blue grit and one coat of neat PVA.
Park life
 

RJW91

New Member
Are you sure just the second coat is coming away? Not rather all your multi both coats are coming away?
Whatever you put on the wall before the multi I don’t think would cause a fail between the two coats? You don’t just place it on the wall but work it in somewhat..
I’m just apprentice standard and know Jack squat anyway

No, it’s definitely just the 2nd/top coat. If I was to dig into the plaster with a filling knife or whatever, the top coat will scrape off very easily and as I first discovered, will delaminate if drilled through, even slowly on a standard/non hammer drill setting.

It’s clearly just the top coat, I can scrape away at it but it leaves the 1st coat there for the scraper to run across. Gonna try and upload a short video of this.

I have tried scraping away at the 1st coat but like I keep saying, it just isn’t shifting, not without a great deal more effort. Maybe it’s the PVA doing as I had hoped, or the fact that it went onto the old render which is a very rough surface, possibly both.

I’m interested in what you all think, regardless of your skill level/experience. Part of me wants to blame it on the plaster itself but I’ll consider the possibility that I have made a mistake somewhere along the line before I resign to that excuse.
 

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RJW91

New Member

Does this happen quite regularly? Again, I don’t want to just blame it on the plaster and call it a day, but it makes me wonder...

I got this stuff from Wickes in Newmarket, just in case anyone else has happened to have stuff from there.

I’ve put more faith buying it from Wickes than most other places. I bought some from Travis Perkins a few years ago now but that seemed to go off quite quick, or so I thought. If I remember correctly they kept it in the open warehouse area so I thought maybe that was why.
 

RJW91

New Member
Omg pva is to be diluted down it says it on the back of the tub, just read the tub it will tell you
I’m similar to the others haven’t a clue what is going on at this job but I do know plastering should never be this hard mate if it’s this hard sometimes it’s best to admit this maybe isn’t the right thing for you

My thinking behind using the PVA neat was something along the lines of:

The old rendered walls are very porous, so this will kill off all suction and give a rookie like me as much time to work with it as possible.

As the old render is providing a good physical key, I can rely on this to help keep the plaster adhered to the wall.

As well as that physical key, I can also rely on the fact that the PVA will liven back up when plastered over and this will also provide a chemical key of sorts to the plaster.

So, with a strong physical and chemical key, the plaster will stick to the walls no problem whatsoever. That’s what I thought anyway and it does seem to have worked, although only with the 1st coat.

It is a pain in the arse, but I’m not going to give up over it, just one of those things. It’s not like I’m buggering up someone else’s house so it really isn’t the end of the world, just an experience to learn from which is why I’ve come here.

I apologise to everyone for my original post being so longwinded, I just wanted to include as much detail as possible. If anyone has picked up on anything that might have caused this problem then please do highlight this so I can avoid this happening again.
 

paulf

Well-Known Member
My thinking behind using the PVA neat was something along the lines of:

The old rendered walls are very porous, so this will kill off all suction and give a rookie like me as much time to work with it as possible.

As the old render is providing a good physical key, I can rely on this to help keep the plaster adhered to the wall.

As well as that physical key, I can also rely on the fact that the PVA will liven back up when plastered over and this will also provide a chemical key of sorts to the plaster.

So, with a strong physical and chemical key, the plaster will stick to the walls no problem whatsoever. That’s what I thought anyway and it does seem to have worked, although only with the 1st coat.

It is a pain in the arse, but I’m not going to give up over it, just one of those things. It’s not like I’m buggering up someone else’s house so it really isn’t the end of the world, just an experience to learn from which is why I’ve come here.

I apologise to everyone for my original post being so longwinded, I just wanted to include as much detail as possible. If anyone has picked up on anything that might have caused this problem then please do highlight this so I can avoid this happening again.
I wouldn't be to sure that neat pva was the best way to go and suction control is something plasterers deal with all the time but you don't want to kill completely with pva.
 

RJW91

New Member
I wouldn't be to sure that neat pva was the best way to go and suction control is something plasterers deal with all the time but you don't want to kill completely with pva.

Is it best to aim for a good balance between physical key, chemical key and suction? Being as inexperienced as I am, if I can eliminate the whole concern of suction control then I just figure it’s going to make it easier for me.

I see products like blue grit advertise themselves as allowing you to plaster over even ceramic tiles, so I just presume that if you can plaster over them or glossy paint for example, then eliminating suction isn’t a big deal?

Say I did control the suction rather than eliminate it, would it make a lot of difference with regards to working time for the plaster? That’s the only reason I thought it would be of benefit to me.
 

RJW91

New Member
Did you PVA on top of your first coat before putting second on?
No, I would wait until the 1st coat is somewhat firm, not so much that it’s set hard, but enough that it is say, putty like. Then on with the second coat, a noticeably wetter mix than the first, could this have been the issue? Making the second mix too runny?

Or are you supposed to PVA the 1st coat before the 2nd?

Also, did you see the video I posted? Can you see what I mean by it scrapes off very easily? Surely multi finish isn’t supposed to be like that?
 

carl-the-plasterer

Well-Known Member
I didn’t want to name them as I gathered the whole neat PVA thing might not go down well.

They certainly seem like they know what they’re doing in their videos.
they all think they know what they're doing pal....nothing could be further from the truth

They're all ego w ankers with not a fkin clue between them
 

paulf

Well-Known Member
Is it best to aim for a good balance between physical key, chemical key and suction? Being as inexperienced as I am, if I can eliminate the whole concern of suction control then I just figure it’s going to make it easier for me.

I see products like blue grit advertise themselves as allowing you to plaster over even ceramic tiles, so I just presume that if you can plaster over them or glossy paint for example, then eliminating suction isn’t a big deal?

Say I did control the suction rather than eliminate it, would it make a lot of difference with regards to working time for the plaster? That’s the only reason I thought it would be of benefit to me.
Grit gives you a mechanical key, pva doesn't, thats why a pre grits get used on tiles.
 

carl-the-plasterer

Well-Known Member
Come on Carl-the-????
Tell @RJW91 why second coat failed out are you scared to publicly comment in case you’re wrong
Out ye jus gonne post a gif?

Napoleon Dynamite Fighting GIF
Come on Carl-the-????
Tell @RJW91 why second coat failed out are you scared to publicly comment in case you’re wrong
Out ye jus gonne post a gif?

Napoleon Dynamite Fighting GIF
I know exactly what he's done wrong, surprised no one else has said it to be honest as it's pretty obvious which actually brings into question do you yourself actually know what the fk ye are doing?
 

MakeItSmooth

Well-Known Member
@RJW91


Bear in mind that cheap contrator-grade PVA is manufactured with a higher water/lower solids content than premium Unibond etc., but even so, as others have remarked, whatever PVA you use should clearly state on the label what the product Manufacturer's recommended dilution ratio is for plastering purposes.

I do dip into youtube every now & then, when I'm bored, and I know of at least one well-known channel that mentions using PVA neat, for plastering purposes (I won't name names, but there is an '.org' somewhere in the name, if I'm remembering correctly).

I don't think you'll find many spreads agreeing with that approach.
 
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