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Questionhow to paint onto new plaster
apparently i need to do a mist coat or 2 to seal the plaster. have been told to use white watered down emulsion to do this. i have a full tin of magnolia matt paint lying around, can i use this or does it have to be white
Hi, A mist coat is essential when preparing fresh plaster for decoration. DIY stores will sell you an expensive product specifically for this purpose, but any light colour of water based emulsion is absolutely fine, so using up spare magnolia is a good idea. I mix up the paint and water in a bucket, and apply with a large brush to minimise the splatter. I know others use rollers, which is quicker, but also messier!
Once the mist coat has been applied, you cando any filling required, and then get on with the emulsion of choice. I hope this has answered your question. Regards, David Clarke (DS Clarke Building Services)
DS Clarke Building Services 29th Jun, 2011
As a plasterer this is the advice i would give the 1st coat can be any colour as long as u water it down this will kill the suction of the new plaster then further 2 coats of the colour u wish to use
M&M Plastering 29th Jun, 2011
1 Consult the plaster container to see how long it takes to dry. Plaster is dry to the touch several hours before it is fully cured and ready to paint.
Go over the plaster with 150-grit sandpaper. This medium-grit sandpaper helps remove rough patches from the new plaster surface.
Sand the plaster again with 300-grit sandpaper. This extra-fine sandpaper takes off a very thin layer of plaster to create a smooth surface.
Wipe down the surface with a damp rag. Don't saturate the rag, as excessive moisture will damage new plaster. Get it barely wet enough to remove the fine sandpaper dust.
Brush general-purpose interior primer over the plaster patch. Use a paintbrush for small surfaces or a roller for larger areas. In most cases, primer isn't needed for the whole wall if it's already covered in latex or oil-based paint.
Paint the primed plaster after it is fully dried. Don't use the same brush or roller that you used with your primer. A fresh brush will be free of unwanted residue, helping you achieve a more accurate color match. Primed plaster patchwork and existing painted walls may need just one coat, but you can apply a second coat if necessary after the first one dries.
GPG home improvement limited 29th Jun, 2011
So long as its emulsion its ok, white is normally used as it shows up any imperfections etc better prior to any filling, plus its easier to cover over.
B J D BUILDING/ROOFING 29th Jun, 2011
All the answers you have received are quite correct, the only exception is if you chose to use vinyl silk as your finish coat you will end up with a shinny ceiling that will show up every imperfection no matter how small, this kind of paint is not light friendly and in my opinion just does not look right on ceilings, but as said this is just my opinion, others may think differently. Best of luck hope all goes well
R.H. Property Maintenance 2nd Jul, 2011
That is fine and i imagine the plasterer/builder was just making a point to water down!
Matt is 100% ok but never use Vinyl silk.
2 coats watered down 50/50 will be fine.
Cannon Preservation 29th Jun, 2011
You can use magnolia or as white emulsion, preferably matt finish to seal new plaster in what we call a mist coat, This should be mixed at a ratio of roughly 40% water and 60% paint so its fairly wet as this coat will soak straight in. It will then require 2- 3 further coats of emulsion.
Artwell Plastering & Tiling 29th Jun, 2011
Idealy you should allow the plaster to dry for at least a couple of weeks. You can paint the new plaster earlier but use a latex paint that allows the plaster to breath. Water down the first coat and then apply further neat coats.
A. D. Services 30th Jun, 2011
That would be fine.
STM & Daughters 29th Jun, 2011
No it does not need to be white the mist coat is to allow the first coat of paint to be absorbed into the plaster new paint is to thick and dries before it has time to adhere to the plaster colour is irrelevant although if you are painting the walls white using a white mist coat would then make sense only for easier coverage
Trident Damp 29th Jun, 2011
i always ease the emulsion with a little drop of water just to let it seal the plaster making it easier for the next coat of paint
Dartnote Ltd 29th Jun, 2011
So long as its a light base colour watered down. Will be fine. 1 coat will prove ok.
NLC Carpentry & Joinery 29th Jun, 2011
you can use any colour you like, obviously wouldnt recommend black if you painting the walls white as a finished colour! but any neutral colours are fine, its just the finish.... it needs to be a matt finish paint.
TB Timber Construction 29th Jun, 2011
You can use it, it just means more top coats if a different colour is needed. Use a contract trade matt to seal. And a vinyl matt for top coats
NORTH WALES DECORATING 30th Jun, 2011
Yes you can use magnolia, it doesnt need to be white paint to do a mist coat.
Hope this helps.
Dannys Decorators 30th Jun, 2011