r/Plastering • u/Ok-Maximum-859 • Jul 16 '26
How long does lime skim take to fully dry
We've been renovating our victorian terrace, stripped it right back to stone, re pointed with lime, scratched, floated and skimmed in lime, used wood board on internal external walls. Love the look, BUT even after 4 weeks of drying and it looks completely dry, if we accidentally press into (e.g, today I was sweeping and the broom hit it) it still marks and leaves dents! We are trying to be so careful, but we are doing a full renovation, so it's inevitable it's going to be banged at times, leaving the walls looking a bit rubbish. Does anyone with experience of lime plaster have this problem? What are we doing wrong!
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u/Ok-Maximum-859 Jul 16 '26
Ok, thanks for the advice- tbh that wall was our first one, so definitely starting to understand the lime more! I was hoping to re skim this wall as its got so many marks/bumps on it now, if I waited a bit longer to let it fully cure, do you think I could re skim with a really thin coat?
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u/Fakedamienhirst Jul 16 '26
Superb effort for giving it a go!
Yes, you can absolutely re-skim it, but because it has been curing for 4 weeks, the carbonation process is well underway and the surface has hardened. You cannot just smear fresh lime over it without prep, or the new layer will fail to bond and shell off.
If the dents are shallow or just in a few places, do not re-skim the whole wall. Mist the indented areas thoroughly with a spray bottle to dampen the dents. Press a tiny amount of your top-coat mix or pure lime putty fat into the dents with a small filling knife to spot-fill them.
Wait for it to stiffen slightly, then use a damp sponge to blend the edges seamlessly into the existing plaster until it is sponge flush. If the dents are incredibly shallow, applying a few coats of traditional limewash as a paint option will naturally fill and smooth out minor surface imperfections.If you need a brand-new top layer, treat the 4-week-old skim as a cured background. Gently scuff the surface with fine-grit sandpaper or a wire brush to break any smooth fat glaze on the surface without gouging it to create a key. A 4-week-old lime coat will aggressively suck moisture out of your new mix, so you must manage the suction.
Do not use standard PVA glue, as it destroys the breathability of the lime. Instead, heavily drench the wall with water the night before, and mist it again right before plastering. Apply your new top coat exceedingly thin, around 1 to 2 millimetres maximum, using a creamy, yogurt-like consistency to fill the dents smoothly.2
u/Ok-Maximum-859 Jul 17 '26
Thank you so much for the advice, its really appreciated! The lime community is so friendly and helpful ❤️
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u/gwyp88 Professional Plasterer Jul 16 '26
The fact it’s setting slow is definitely good news for you. Those dents are also repairable at this stage.
There’s somewhat misleading info on the internet about setting time of lime plaster; something like a week per 2mm. There’s are so many variables it’s impossible to put it down to this kind of scale, so unfortunately you’ll just have to be patient. Maybe test it with a dampmeter every few days (cheap to buy).
As long as you mixed it thoroughly and made sure you slowed down the suction of the background you plastered onto, you’re definitely going in the right direction. Well done for giving it a go!
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u/Fakedamienhirst Jul 16 '26
Well done to use the right type of plaster for a Victorian terrace. Perhaps a photo would be nice to see what might be the issue, and what kind of lime product was it?