Fri, 01 May 2026 02:58:15 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=233741#Comment_233741 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=233741#Comment_233741 Tue, 15 Dec 2015 17:47:55 +0000 bot de paille
If you want to put a skim lime plaster on to plasterboard this is a tried and tested solution. Also works on any wall surface that you want to skim as part of a renovation. I came up with it because Multifinish plaster doesnt exist in France and the local plaster is shite for skim finishing because it sets very quickly.

Prep the plasterboard or existing wall with 9 parts water and 1 part PVA glue which has sand mixed in. This will seal the wall and provide a mechanical fix. I wait until the PVA has set but still a bit tacky...

then plaster on the skim coat of lime/sand plaster. Mix 1 part NHL3 lime with 1 part sand and mix together using the same PVA/water mix used for the primer.
Use a fine, nice colored sand as it is this which will determine the final color of the plaster. Quartz sand can also be added.

And thats it. Finish the plaster as you want, either flat finish with a trowel or bring out the sand using a sponge when the plaster starts to set after a few hours.

If you live in one of those countries that uses gypsum plaster that sets within 20 mins, the missing ingredient you need to add to increase working time is trisodium citrate, a form of citric acid. You can also squeeze some lemon juice into the water as you mix the plaster. If you add too much the plaster wont set.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305574#Comment_305574 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305574#Comment_305574 Tue, 19 Mar 2024 21:59:58 +0000 Mike1 Posted By: bot de pailleIf you want to put a skim lime plaster on to plasterboard this is a tried and tested solution.A long time since this was posted, but I may give it a try!
Just wondering how thin you were able to apply it and how it's held up since?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305575#Comment_305575 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305575#Comment_305575 Tue, 19 Mar 2024 23:03:12 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305577#Comment_305577 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305577#Comment_305577 Wed, 20 Mar 2024 11:20:22 +0000 djh Posted By: fostertomI'll guess this converts lovely breatheable lime plaster into a vapour barrier?Depends whether you use vapour permeable plasterboard or not!

BTW, if you don't want the yellowish colour of sand, you can use chalk instead. Various merchants sell bags of it.

edit to add: "The gypsum core is inherently porous, but the plasterboard's facing layers contribute to its vapour resistance."]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305578#Comment_305578 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305578#Comment_305578 Wed, 20 Mar 2024 12:13:54 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305579#Comment_305579 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305579#Comment_305579 Wed, 20 Mar 2024 15:09:40 +0000 djh Posted By: fostertomThat's an alert - I've always 'known' that pbd is vap permeable.You're the one that said it would make lime a vapour barrier?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305580#Comment_305580 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305580#Comment_305580 Wed, 20 Mar 2024 16:39:27 +0000 Peter_in_Hungary https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305584#Comment_305584 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305584#Comment_305584 Thu, 21 Mar 2024 00:50:25 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305585#Comment_305585 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305585#Comment_305585 Thu, 21 Mar 2024 09:58:57 +0000 owlman ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305586#Comment_305586 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305586#Comment_305586 Thu, 21 Mar 2024 12:52:33 +0000 djh https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305587#Comment_305587 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305587#Comment_305587 Thu, 21 Mar 2024 13:10:45 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305618#Comment_305618 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305618#Comment_305618 Tue, 26 Mar 2024 12:44:25 +0000 Mike1 Posted By: djhIs PVA a vapour barrier? I see lots of reports of additives that can be used to increase its vapour resistance?Good question - and I can't readily spot an answer. Anyone?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305643#Comment_305643 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13890&Focus=305643#Comment_305643 Wed, 03 Apr 2024 18:19:46 +0100 kristeva