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Plastering over paint

Im plastering over a painted surface, dont know what paint it is all i know is that its old, how should i treat the surface befor plastering

24 Answers from MyBuilder Plasterers

Best Answer

Firstly make sure it’s a sound surface with no blown plaster if it’s an old building then remove all lose paint make sure it’s dust free then apply a mix of unibond a little sbr and a hand full of building sand keep mixing and apply to wall,or buy pre mixed expensive grit, the guy that taught me has been using that method for over 25 yrs so it’s tried and tested


Answered 10th Dec 2017

The best option is to try and get as much of the paint off, sand the wall, cover the area with PVA glue allow to dry and pain over it. Add some PVA to the paint as well and you will have great results///


Answered 5th Nov 2017

Scrape all lose parts of paint and brush it down to remove dust etc and apply thistle bond it additive with a roller,leave to soak in for 24hrs then your ready to plaster.


Answered 16th May 2020

In my personal opinion and experience, scrape any lose and blue/green grit the wall, leave it to dry then plaster, jobs a gooden 👍🏼


Answered 13th Nov 2017

Always scrape back any flakey bits of paint and brush away dust. Also make sure the plaster hasn’t blown in any places. Follow it up with 2 coats of Pva.


Answered 20th Dec 2017

Scrape any loose paint, scrim any air line cracks, give the walls two coats of PVA, when dried apply two coats plaster.


Answered 11th Jan 2018

Clean wall down then apply a coat of p.v.a over the wall you don't need to put 2 coat on just one coat


Answered 9th Jun 2018

Make sure all old flaky paint is removed, 2 coat pva the wall, make sure none of the wall is loose, then when plastering look for cracks and Skrim tape before skimming


Answered 18th Mar 2019

I personally would scrape the surface thoroughly to remove any loose paint, then scratch the surface with wavy lines (cracks always travel in a straight line) to provide a key for the plaster to adhere to and then either to coats of pva the night before or one coat of a plasterers primer such as thistle bond-it, sovereign plasprime or feb bond blue grit as this this will seal the surface and also provide a mechanical key which you will not get with pva.


Answered 16th Nov 2017

Any painted walls , you would have to make sure all flakey paint has been removed , add a jey if necessary possibly a sand down or a light scratching to give a suction , two coats of pva untill tacky sometimes adding a small amount of sand to the pva can help for a key , then two voats of multi finish should do the job


Answered 1st Feb 2018

Personally I would suggest removing any loose paint then a bonding agent applied.. thistle bond it for example then skim


Answered 12th Apr 2018

Scrape any loose paint flakes off, give the wall a coat of pva if the wall sucks up quickly give it another coat of pva, if not one coat will do because its been painted.


Answered 15th Jan 2019

Prepare painted wall by scraping any loose paint then pva 2 coats be careful if you are disconecting any electrical sockets and switches you dont get any pva glue on any terminals this could trip electrics also i find it best to use a wide paint brush rather than a roller when priming old flakey walls if walls are really bad you can also used thistle bond but this product is exspensive suitible for bad walls celings hope this helps city plastering


Answered 30th Jan 2019

You or the person that will be doing the job will need too remove all flakey paint off &other material that might be sticking out check for old nails in wall that be bidding that might rust through.the wall before pva and pva 50/50 a empty the pva tub in a bucket then re-fill the empty pva tub with water all the way shake it empty it into the buckets with pva and mix it.and apply one coat onto background
Make sure holes are be done and cutting in too don’t let pva get on any non plasterd painted wall if so wash off with water before the fist coat has been put on leave for 10/15 minutes then apply a second coat same again leave intel the wall is sticky tacky. Any hair line cracks you see apply with scrim tape only when the pva has gone off the wall.if not sicking ones mixed plaster up use some plaster too help the skrim say in places .2coat plaster ready to start.


Answered 21st Apr 2019

Pretty much the same as what everyone has said scrape loose paint off and sand slightly I prefer thistle bond it to pva as you get a nice key to work to but 2 coats of pva will do nicely give it one allow to dry then a second a plaster when pva gone tacky but not too wet that the plaster will slide off


Answered 17th Nov 2017

The wall scraped free from flaky paint sanded down and two coats of PVA before plastering


Answered 4th Nov 2017

Scrape flakey paint,
Rub down with a piece of sandpaper to ensure nothing flakes off the wall then two coats of pva


Answered 4th Nov 2017

In my opinion it is always best to clear the wall off any loose paint and dust. Some plasterers will do two or even three passes of pva. but backgrounds like this with no key are best treated with a gritted stablising primer. This primer will not just stop the suction to allow for plastering but will also other a mechanical key for the plaster to grip to. There are lots of choices of these primer's out there all ranging in price from £25 to £70. Always be sure to read the lable and follow the manufacturer instructions and use the proper PPE


Answered 5th Dec 2017

When plastering over old painted walls you should allways make sure the walls are free from flakey paint scrape well if needed and I'd allways advise thistle bond it (blue grit ) on old walls as this will make sure the walls are sealed and give you a good key to plaster over make sure any cracks are taped over using scrim and any blown spots you might come across hack off and bond in .. hope this helps you kind regards akplastering


Answered 30th Jan 2018

Your best bet is to give the wall a light scrape to get any excess paint/ dust etc off. Give it good coat of Pva mixed with a splash of water.


Answered 15th Mar 2018

If it’s glossy paint I always use thistle bond it, if matt paint I pva twice


Answered 23rd Mar 2018

Rubb down with sand paper give it a good scrap making sure there no lose paint and my personal preference is to use a special gritty PVA alow to dry for 24 hours


Answered 22nd May 2018

Make sure all flakey paint is taken off, cover all major cracks with fibre tape (skrim tape) to make sure the finished plaster doesn’t crack. mix up some pva and water together not too thick or runny, apply an even coat over the wall so it is sticky/tacky with either a brush or a roller. Wait until the pva has dried and this would fully prepped for plastering over.


Answered 5th Feb 2019

All paint should be removed and sanded down fully before skimming.


Answered 5th Feb 2019

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