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How 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?

29 Answers from MyBuilder Painters & Decorators

Best Answer

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)


Answered 13th Mar 2019

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


Answered 30th Jun 2011

Use any light matt emulsion to seal new plaster in what we call a mist coat, This should be mixed at a ratio of roughly 20% water and 80% paint, this coat will soak straight in. You can apply with a brush or roller. It will then require a further 2 coats of whatever colour you choose.


Answered 3rd Jan 2016

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.
2. Go over the plaster with 150-grit sandpaper. This medium-grit sandpaper helps remove rough patches from the new plaster surface.
3. 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.
4. 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.
5. 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.
6. 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.


Answered 11th Apr 2019

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.

Good luck.
Scott Cannon.


Answered 30th 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


Answered 3rd Jul 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.


Answered 30th 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.


Answered 30th 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


Answered 30th 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


Answered 30th 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.


Answered 30th Jun 2011

Yes you can use magnolia, it doesnt need to be white paint to do a mist coat.
Hope this helps.


Answered 30th Jun 2011

Hi there for best results in this case for painting over freshly plasterd walls is let the plaster dry for anything up to a week your first two coats of paint should be mixed with water so it can take to the wall after that it should be fine to paint as normal hope this answers your question good luck.


Answered 22nd Jul 2016

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


Answered 30th Jun 2011

So long as its a light base colour watered down. Will be fine. 1 coat will prove ok.


Answered 30th Jun 2011

A mist cost is a must as the , you can buy a product from most DIY stores but the cheapest way is to water down that old tub of emulsion you've had in your shed for a while magnolia works aswell brush for thicker coat 2-3 coats on fresh plaster 😬 Thanks Craig (Ccraigiedecorators)


Answered 28th Feb 2017

A coat of fog is essential for the preparation of fresh plasters for decoration. Do-it-yourself stores sell you an expensive product specifically for this purpose, but any light color of the water-based emulsion is absolutely fine, so using a stock magnolia is a good idea. Mix the paint and water in a bucket and apply with a large brush to minimize splashing. I know others use the rollers, which is faster, but even crazier!
Once the anti-fog coating has been applied, it is necessary to fill any filler, then proceed with the emulsion of choice. I hope this has answered your question. Sincerely, MCI Paynting & Decoration


Answered 1st Feb 2018

We've just had our walls skimmed, and we're now ready to paint them. Some places are recommending sanding the walls before painting. Is this necessary if they've just been skimmed? Or can we go straight to the water down emulsion as a primer for the walls?


Answered 6th Feb 2019

The mist coat isa base coat of watered down emulsion paint it is essential to apply a mist coat because if you just paint standard consistency emulsion on newly plastered walls the chances are that the paint will peak off as it won’t have a chance to properly sink into the plaster however in my view you should make it as watery as you can to give the paint the maximum chance of sinking into the plaster so I go for a ratio of 50:50 paint to water this also saves you money as the paint you’ Using for the mist coat goes a lot further make sure your plaster has dried out completely before painting on your base coat and again mark sure the mist coat has completely dried before applying the fi


Answered 29th Sep 2018

Hi, To paint a new Plaster first off all you will need prepare the new plaster, sanding down if required you need to see if the plaster is like a mirrow you must need sanding down gently, for the wall absorve the the first coat(mist coat) mist coat that,need be quiet liquid to have a good absorvation. after that you can one normal coat. than repair where is necessary,than touch up the patch and give the top coat.


Answered 5th Jan 2018

Hi. First What u will have to when plaster is Dry is a SANDING DOWN All surface and edges. Use 80 grid sand paper. After this brush of dust and Then u can mix paint with water ;) for a mix coat can be Any cheap paint . After this u can fill All holes and sand this down again. Then ur surface will be prep. For Top coats. ;)


Answered 14th Mar 2019

To paint new plaster you should let the plaster dry and settle first so there’s no dark patches then mix water with paint 30% water 70% paint and mix thoroughly this is called a mist coat one the mist cost has dry you can paint the walls with normal paint the point of the mist coat is that it seals the new plaster it sucks the water from the paint the water and seals the plaster


Answered 3rd Jan 2019

As a plaster 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 coat of the colour u wish to use


Answered 4th Jun 2022

Use any light matt emulsion to seal new plaster
Use a ratio of 50/50 paint to water


Answered 15th Sep 2022

Use a 50/50 mix of paint and water for the 1 coat then normal paint


Answered 7th Dec 2022

Mix 50/50 paint to water, it’s also called a mist coat

thanks Jack


Answered 20th Mar 2023

Paint with watered down emulsion


Answered 30th Apr 2023

One part water one part paint. Worked for me in the past


Answered 28th Sep 2023

Yes mist coat.


Answered 5th Nov 2023

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