Plasterer didn't tape joins

[carl1t0]

The guy who skimmed the plasterboard in our utility room last week doesn't seem to have used scrim tape on the walls or on any of the internal corners (but he did put tape on the ceiling joins). Now we have hairline cracks in the walls along many of the board joins. The corners around the ceiling haven't cracked yet but I expect them to before long. He needs to come back and finish two walls but first I need to decide whether I really want him to continue and how to fix things.

He's already skimmed the ceiling and two walls but two more walls remain. Is it worth scraping off the skim around the edges of the ceiling and in the corners so that I can tape before the final walls are skimmed?

I've come up with the options below for fixing the cracks but none of them seem ideal. Any further suggestions? Is this even worth worrying about?

• 
  a) Scrape off a few mm of skim each side of the cracks the width of the scrim tape, stick the tape on, PVA, multifinish. I've done this for small holes that needed filling with a small square of board. No cracks yet but the skim is hard to scrape off.
  
  b) Use a belt sander or angle grinder or drill with a flap wheel or disc instead of scraping, then do as above. Very dusty.
  
  c) Use some magic filler and hope that the cracks don't appear again. Is this even worth trying when I know that the joins haven't been taped?
  
  d) PVA the whole wall and ceiling, tape, and get everything skimmed properly. Extra time and expense.
  
  e) PVA, tape and overskim just the cracks. Sounds like there would be a visible bulge in the wall.

For the internal corners I could just forget about taping them and put a bead of decorators caulk before painting. Hopefully if it cracks, the caulk will flex and it won't show.

Full story for what it's worth. We took a bit of a risk and had a friend do the work. We'd heard he was good at plastering and he needed the work, plus the finish of the room isn't critical. I plasterboarded the room myself but I've tried skimming before and it didn't go too well so I thought I'd get someone else in. Turns out this friend is pretty good with a trowel and to be fair he got a nice smooth finish but he doesn't know or doesn't care about "details" like tape. My wife was around while he was working and she saw him tape the ceiling before he started but I can tell that he hasn't taped any of the internal corners and I can't see any sign of tape on any of the walls that are cracking. It's possible that the boards have moved a bit but I really don't think that's the problem here. No cracks in the ceiling where I would expect the most movement.

 

[roughcaster]

Sorry mate, i think your friend is a chancer!! Don't mess about with sanders, angle grinders, magic fillers or any other so called "fixes". Start off by getting a plasterer who knows his job. As has been said before on here, skimming is the "simplest" form of plastering in the world,, easy, but to plaster plasterboarded walls without taping the joints is un-forgiveable. Start again,, get a real plasterer in, TAPE ALL THE JOINTS, pva all the walls to seal them, let them dry, pva them again as you go, then re-skim each wall while the pva is still wet/tacky. You can have the best finished walls in the world, but if the prep underneath is missing, the jobs a dud.

 

[stevethespreader]

No need to reskim everything again tape and joint will be good enough

 

[carl1t0]

Thanks, roughcaster. I was afraid of that. I'm tempted to give it a go myself as I'd like to learn. I know enough to do the prep work properly but I don't think I'd be much good at getting a smooth finish. Probably just pay to get it done. The guy who did the rest of the house did a great job and not a crack in sight.

 

[roughcaster]

I'd tape and re-skim the 2 affected walls and here's why,,,,, a far better job than just tape and joint the cracks, far quicker, all done in one go, no sanding down.

 

[carl1t0]

Steve, I didn't see your post earlier. What would you use to join over the tape? East fill then sand down? Will it stick to the skim coat ok? Won't it leave a visible ridge on the wall?

I'm sure roughcaster is right about getting the best finish but if I can fix it myself I'll give it a go. To be honest I'd rather have my walls a bit uneven but with no cracks.

 

[NickB_99]

I plasterboarded the room myself ........
It's possible that the boards have moved a bit but I really don't think that's the problem here. No cracks in the ceiling where I would expect the most movement.

Hi Carl.
Whichever route you go to remedy, your boards must be well fixed. Any movement in the boards will be bad - you would get cracks even with scrim tape.
How were the boards fixed to the walls of the utility room?
If using drywall screws into wood, then may be put some more screws in to be sure. Check for any board edges that give at all.
If using dot/dab adhesive, you must support the board edges all the way round with a decent amount of adhesive in the middle too. If it was d&d and there is spring in the boards at the edges, then your options are more limited to repair.

No sense in perhaps paying for a full re skim if it's not sound underneath.

 

[stevethespreader]

Steve, I didn't see your post earlier. What would you use to join over the tape? East fill then sand down? Will it stick to the skim coat ok? Won't it leave a visible ridge on the wall?

I'm sure roughcaster is right about getting the best finish but if I can fix it myself I'll give it a go. To be honest I'd rather have my walls a bit uneven but with no cracks.

yes easifill tape the joints (paper tape) is best for ceiling lines but mesh scrim can be used in your small room get a taping knife or trowel and apply 2 coats feathering out the second coat very easy job , go in my profile there is a 100m lid I done that was taped after I skimmed it at Southampton fc training ground 90% of the plastering was done this way on that job because there was a mixture of taping and jointing and plastering so most ceiling lines were taped

 

[carl1t0]

yes easifill tape the joints (paper tape) is best for ceiling lines but mesh scrim can be used in your small room get a taping knife or trowel and apply 2 coats feathering out the second coat very easy job , go in my profile there is a 100m lid I done that was taped after I skimmed it at Southampton fc training ground 90% of the plastering was done this way on that job because there was a mixture of taping and jointing and plastering so most ceiling lines were taped

OK. Thanks for the idea. Can't see your profile though. It says it's private.

 

[carl1t0]

Hi Carl.
Whichever route you go to remedy, your boards must be well fixed. Any movement in the boards will be bad - you would get cracks even with scrim tape.
How were the boards fixed to the walls of the utility room? ...

No sense in perhaps paying for a full re skim if it's not sound underneath.

Good point but I couldn't see any movement before it was skimmed and even now I can't see any movement in the cracks when I push on the wall. The walls with the cracked skim are solid, not stud walls, so doors slamming shouldn't cause any movement, and nobody has touched the boards since they were skimmed. Of course, if I bump into the wall or shove a washing machine into it I wouldn't be surprised if it cracked but I'll do my best to avoid that

On the two walls that have been skimmed I stuck the boards on with adhesive foam because the wall underneath was reasonably flat and smooth (but had cracks in them and holes in places). I used the same foam in our bathroom a year ago and haven't had any cracking there. It's denser and harder than regular expanding foam. The remaining walls are battened and with plenty of screws along the edges I'm sure those will be fine.

I think the cracks happened in this case because the skim shrinks a bit as it dries and the untaped joins are the weakest spot, not because of movement. If the taping had been done properly and the walls had cracked, I'd have been happy to take the blame myself

 

[stevethespreader]

yes easifill tape the joints (paper tape) is best for ceiling lines but mesh scrim can be used in your small room get a taping knife or trowel and apply 2 coats feathering out the second coat very easy job , go in my profile there is a 100m lid I done that was taped after I skimmed it at Southampton fc training ground 90% of the plastering was done this way on that job because there was a mixture of taping and jointing and plastering so most ceiling lines were taped

OK. Thanks for the idea. Can't see your profile though. It says it's private.

sorted

 

[carl1t0]

I've got a plasterer coming in to overskim everything. He asked me to paint Thistle Bond-it over all the old skim. It took the best part of a 10kg tub to cover the ceiling and both walls. Cost £45 which is the cheapest I've seen it.

For those who haven't used it before, it's like a blue PVA with sand in it. I believe there's something similar called Blue Grit that can be ordered online and is quite a bit cheaper. Mix well before use or all the sand stays at the bottom. I'm glad I taped over the cracks first because it's quite thick and I can't tell where they are anymore.

 

[stevethespreader]

Thistle bond it is green , blue grit has a lager aggregate than bondit did you tape the joints first before you put the bond it on?

 

[roughcaster]

I've got a plasterer coming in to overskim everything.

Definitely the best way to go,, all done in one, finished.

 

[carl1t0]

Steve, green or blue, let's call it turquoise. I taped the joins on the wall before putting the Bond-it on but not the corners where the walls meet the ceiling.

Roughcaster, yeah, it's the simplest and best solution but also the most expensive. At least I know this plasterer will do a great job because he did the rest of the house. I haven't been convinced by the work some other trades have done and figure I could have done better myself at tiling, running pipes, and fitting the flue for the boiler.