Painting Over Plaster

[jmanjmanj]

Hi
I've just had my walls skimmed about a week ago and now want to paint them.

Someone mentioned that I need to paint over the plaster with something to kill off 'bacteria' first and others have said that i should water down emulsion (add 20% water) and put a coat of this on first.

Can someone give me advise on what I should do?

thanks

 

[Zampa]

Whoever said you need to paint it to kill off bacteria has been eating to many orange coloured smarties!

All you need to do is...

Thin the first coat by about 25-30%

Rub the walls down...

appy two more coats thined by about 15% rubibng down betwen each coat.

Use matt not silk emulsion

 

[AndersonC]

Sorry if this is a bit of a hijack...........Zampa do the three coats that you describe in their various states of dilution need to be the same colour as the final top coat? Could you apply the first coat in, say, white then apply two coats of your desired colour over that?

Also would you thin down really cheap paint like B&Q value which has probably already been thinned?!

 

[Zampa]

The first (mist) coat can be anything really.

B&Q value paint is really a bit of a false economy..if you already have then you may as well use it but otherwise if the plaster is just a skim id personally go for a vinyl matt.

Bear in mind you ownt be able to thin value paints as much as decent ones..no more than about 20%...as a comparision I have thinned dulux supermatt, which is the trade name for the 'paint for new plaster' by 50%

 

[LucyMoo]

when you say rub the walls down, pls can you explain? newbie at painting

i heard its better to use a pva sealer rather than thinned emulsion for first coat? true?

 

[Zampa]

when you say rub the walls down, pls can you explain? newbie at painting

i heard its better to use a pva sealer rather than thinned emulsion for first coat? true?

Rub the walls down with 100 grade abrasive paper....fold into a square and rub the walls with the rough side..in a circlular motion, but dont rub the bare plaster you will scratch it to pieces....rub down after you have done the first (mist coat) of emulsion

Forget about the PVA its an old wifes tail put about by people who dont know what they are doing of,...its not standard practice and you wont find ity decorating literature...your not 'sealing' the walls your priming them.

 

[LucyMoo]

thanks, so just normal white matt emlusion watered down will suffice for the initial coat

how do you measure how much water you are using when watering it down?

 

[Zampa]

What I would do is pour the tin into a bucket and then fill the tin up a quarter full of water

 

[Third_Eye]

thanks, so just normal white matt emlusion watered down will suffice for the initial coat

how do you measure how much water you are using when watering it down?

There is no such thing as "normal white emulsion" "LucyMoo". Beware of Dulux Rich Matt and Onecoat Emulsions.

 

[AndersonC]

The first (mist) coat can be anything really.

B&Q value paint is really a bit of a false economy..if you already have then you may as well use it but otherwise if the plaster is just a skim id personally go for a vinyl matt.

Yes I think a more appropriate word would be "cheap" since value is related to the product doing a good job at a reasonable price, something that B&Q value does not do - the coverage is horrendous.

I've bought some decent trade vinyl matt - might as well do the job properly.

 

[LucyMoo]

thanks guys, you are great help !

so am i right to understand this for my smooth skimmed walls..

1. mist coat in vynl matt trade watered down 25%
2. quick rub down
2. another coat of desired colour in vinyl matt trade watered down 15%
3. final coat of desired colour in vinyl matt trade watered down 15%

is this right?

so for the initial mist coat il be fine with the dulux trade matt paint in white then?

how much will i need for a lounge which is 22 ft x 10 ft - not high ceiling as its failry new property - the walls have been skimmed and smooth as a babys bum, something i want after painted aswell

also colour guard dulux matt ok for desired paint (they say its 10 times tougher) or shall i stick with dulux matt trade?

thanks m8

 

[trotter]

thanks guys, you are great help !

so am i right to understand this for my smooth skimmed walls..

1. mist coat in vynl matt trade watered down 25%
2. quick rub down
2. another coat of desired colour in vinyl matt trade watered down 15%
3. final coat of desired colour in vinyl matt trade watered down 15%

is this right?

so for the initial mist coat il be fine with the dulux trade matt paint in white then?

how much will i need for a lounge which is 22 ft x 10 ft - not high ceiling as its failry new property - the walls have been skimmed and smooth as a babys bum, something i want after painted aswell

also colour guard dulux matt ok for desired paint (they say its 10 times tougher) or shall i stick with dulux matt trade?

thanks m8

First of all, the paint you are after for your mist coat is 'Dulux trade vinyl matt'. It's hard to believe but leaving out / getting wrong one word - vinyl, or trade or matt - could make all the difference !!! I would go for white then whatever you paint on top, however light the shade, will be OK.

Secondly - I thin Dulux trade vinyl matt by 50%. It's amazingly thick. You don't want to apply it thick for your a mist coat, you wil have trouble later if you do.

Third I would say 5 litres will just about do a room that size - £25 or so for that much.

 

[LucyMoo]

thanks trotter,

so would it just not makes sense then to get thin paint for the mist coat e.g some cheap brand.. then no need to water down if the vinly matt trade is really that thick?

best place for dulux trade vinyl matt? b+q where they mix it for you?

i cant wait to get started.. what roller shall i get guys, new skimmed walls

thx

 

[jmanjmanj]

Brilliant replies thanks very much!

Now where is teh best place to buy 'Dulux trade vinyl matt'?

Thanks
Nick

 

[trotter]

thanks trotter,

so would it just not makes sense then to get thin paint for the mist coat e.g some cheap brand.. then no need to water down if the vinly matt trade is really that thick?

best place for dulux trade vinyl matt? b+q where they mix it for you?

i cant wait to get started.. what roller shall i get guys, new skimmed walls

thx

Well, I would advise getting the Dulux trade vinyl matt. Cheaper paint is a false economy, you'll use more paint (and hence buy more) and you may end up having to do another coat - for the sake of an extra tenner you may as well get the job done properly, first go!

Bear in mind if you do buy cheaper, you need to water down whatever you buy, as the plaster will be thirsty. You will just need to thin it down less than Dulux trade. Maybe 25% to be safe.

The mist coat should look 'misty' (surprise surprise!!) or 'patchy', you do not want it looking like a top coat when applied. It's too thick if it does. Stop and water down more.

In terms of where to get the Dulux paint, you'll find it in B&Q, Dulux decorator centres, it's widely stocked to be honest... don't need to buy a 'mix' for your mist coat...it comes in tins !! I honestly don't know the cheapest source of Dulux trade paints. Have a google...