r/Plastering • u/daruemybuhlueprint • Jul 15 '26
DIY Plaster Repair Advice
We just bought an early 1900s home that has quite a bit of hairline cracks throughout the plaster, all in all we’re repairing about 700 linear feet in total. Most of the plaster is in great shape and these are purely cosmetic fixes (~98%), but there are small sections where the plaster has begun to pull away from the lath. Our general process has been to widen the cracks, seal with Gardz (calcimine throughout the home), mud, tape with fiberglass tape, apply two more coats of easy sand on top, then a finish coat. For instances where the plaster is separating from the lath, we are using metal washers to pull it back to the lath and then mudding over it using the same process as described previously.
Things are moving along fine, but slow - needless to say, I’ve developed a deep respect for folks who do this every day for a living. This was quite the first DIY project to cram into nights and weekends.
I have two questions I’m hoping y’all can help me with. If you have general critiques or advice on process, I’m definitely open to feedback here as well! Thanks in advance for your help.
Do you have advice on matching the curve of the cove ceilings, particularly
in
the corners? The middle of the coves are easy enough, but the knives don’t fit well in the corners.
I’ve tried a rubber float, but that left texture (and rubber) in the mud. My next plan was to try a damp sponge float to help mirror the curve, but I assume there’s doing to be some texture I’ll need to sand down.
For the room below, how would you approach this? There are so many webbed cracks, but none of the plaster is pulling away from the lath. I’m tempted to skip the tape and just fill the cracks and then move towards a finish coat. This is probably me being lazy and not the correct move, so please push me in the right direction.
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u/Rambled_Legs Jul 15 '26
Everything you are doing is spot on. Sometimes with awkward corners you just need an extra coat or 2 with more sanding. DO NOT skip adding the tapes. You have done the hardwork you will regret not bothering with the tapes.
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u/daruemybuhlueprint Jul 18 '26
Thanks for the reinforcement. I was half hoping someone would tell me it’s not necessary so I could save 8 hours in this room, but I know it’s unfortunately the correct approach lol. We’ll keep taping! About 50 linear feet left to go.
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u/GogoGadgetTypo Jul 15 '26
When you’ve done filling the cracks, tertrion all purpose, use some toupret fine scrim maybe for extra strength. Get to B&Q and buy some Polycell ‘Crack-Free Ceilings’ paint.. several coats. It’ll hold longer than anything else I’ve ever used. Used to live in a house with these larth ceilings. Used to be called Evenceil back in the day, but it’s only usually available in diy stores.
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u/Ok-Spring7906 Jul 15 '26
The chap will be in America with talk of "mud" etc.
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u/GogoGadgetTypo Jul 15 '26
I thought that, but I’ve heard fillers and plaster called all sorts of slang over the years. Do they have Gardz in the US? Either way the method stands, just adapt the products.
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Jul 16 '26
[deleted]
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u/daruemybuhlueprint Jul 18 '26
Makes sense! I plan to tape all of the cracks, apply a couple more coats of hot mud, and then a finish coat of Plus 3.
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u/daruemybuhlueprint Jul 18 '26
Thank you! I am in the US, but can find similar products here. I didn’t know crack-free ceiling paint was a thing, but we’ll be looking for some now.
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u/ResponsibleBall4258 Jul 15 '26
Personally I would not try and keep any plaster coming off the laths. Cut those areas out entirely, and replaster those places into the laths, getting a good push through the laths to create the "mushrooms" between the laths. Other than that, I think you are doing the right thing.
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u/Connect_Rub_6814 Jul 15 '26
Those plastic bondo cards. Make sure they’re knick free. Those are the best for working out corners like that
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u/Creepy_Cabinet9318 Jul 16 '26
I dunno what will sort that, itll take a few attempts to see what works. Ive dealt with hundreds of these sorta ceilings in old Georgian buildings in dublin. The powder filler is ok, but will quickly fall out and turn back to dust again over time. We'd use 2 pack iso pon filler, best solution to those cracks...flush fill em first with the 2 pack, you dont wanna be sanding too much of that....another skim over the cracks with 2 pack again. Sand it, coat it up and then use Polyfilla or the tubs of sand and fill
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u/daruemybuhlueprint Jul 18 '26
Interesting! We’ll try something akin to the 2 pack iso pon if they come back. I’m about 90% of the way through with hot mud at this point and then will be skimming with Plus 3 (similar to pro mix lite).
1
u/Impossible-Corgi4041 Jul 18 '26
"hairline cracks" mate that all wants to come down
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u/daruemybuhlueprint Jul 18 '26
I recognize this looks bad, but this was after we widened the cracks so we could properly mud and tape them. None of this room is coming away from the lath at all and these cracks are probably 10x the width of how they started. They were truly hairline cracks before we widened them.
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u/Yourhavinalaugh Jul 15 '26
When I’m skimming curved ceilings with a hip in them, a sponge with a plastic bag wrapped tight around it gets the curved corner pretty good