Paint Opacity on thirsty Plaster or Artex

[gettingbetter]

I was having artex peeling problems in this thread:
//www.diynot.com/forums/viewtopic.php?p=1455012#1455012

I'm now on to the issue not of peeling, but of making a topcoat actually show up as white ... and this seemed like a different topic that may affect a lot of people painting ceilings that have either artex or fresh plaster, so I've posted it here as a new topic.

I painted my newly artexed ceiling using B&Q Colours Pure Brilliant White Matt Emulsion. After several coats, the ceiling still looks off-white, with the artex colour showing through somewhat. I take this to mean that the covering power of the B&Q paint is poor, OR that the artex is too thirsty for any paint and requires sealing first.

I'm changing paint in the hope of getting better whiteness (opacity).

I've now bought Dulux Trade Supermatt thinking it is ideal for new artex as I read that you shouldn't cover new artex in a matt containing vinyl. But, I'm a bit worried about using the Supermatt now because it is just White (everything else is Pure Brilliant White). So my questions are these:

1. If I seal the whole ceiling in Uncercoat or BIN, can I use a vinyl matt without any problems?

2. In fact, for future reference when painting over artex or plaster, instead of mistcoating and being restricted on paint to non-vinyls, isn't it better just to seal the whole ceiling with Undercoat/BIN and then use any paint you like on top (including vinyl) because the sealing prevents the thirstiness of the artex from causing problems?

If the seal+choose any paint you like option is best, I think I'll go for Dulux Trade Vinyl Matt or Flat Matt or something else that is available in Pure Brilliant White instead of just white, and also that forms a neater film rather than what I've read re Supermatt as being a chalky finish that will come off with a wet sponge(true?).

Cheers.

 

[LJW61]

A couple of coats of Crown or Dulux Brilliant White vinyl matt will cover that c****y B&Q no problem ..Dont worry about BIN or primer as the watery old DIY stuff will have acted as a 'mist' coat

 

[opps]

I agree that B&Q is crap.

I would not want to paint an artex ceiling with BIN- it is too runny and will go everywhere.

All emulsions have vinyl but you are correct that the Supermatt has less.

I used to use it but the lower acrylic content means that it smudges extremely easily.

Also make sure that the artex is really dry and not just touch dry. I once painted new cornice not realising that it was only made a couple of days earlier- two days after painting it was pink.

 

[gettingbetter]

Thanks for the replies.

So I've read many times advice to use Supermatt on new plaster or artex, because the low vinyl means it won't form as much of a film that can peel off ... but what I'm saying is, surely if the plaster/artex were to be sealed beforehand using an oil/shellac based paint (like undercoat or Bin), you could use absolutely any emulsion on top with no peeling problems, even a high vinyl one.

Is that a correct assumption?

 

[LJW61]

Overkill - It would be complicating (& more expensive)what is normally a simple mornings work to apply 2-3 coat of emulsion ...

 

[gettingbetter]

So I can use e.g. Dulux Trade Vinyl Matt directly onto new artex with no problems as long as the first 1 or 2 coats are watered down?

There's no problem using a high vinyl-content paint on new artex?

 

[opps]

Thanks for the replies.

So I've read many times advice to use Supermatt on new plaster or artex, because the low vinyl means it won't form as much of a film that can peel off ... but what I'm saying is, surely if the plaster/artex were to be sealed beforehand using an oil/shellac based paint (like undercoat or Bin), you could use absolutely any emulsion on top with no peeling problems, even a high vinyl one.

Is that a correct assumption?

So long as the paster/artex is fully cured/dry then yes you could use most paint types.

BIN is not ideal as a primer for plaster, water based products are better.
I recommend bin over problem emulsion not as a primer. It would also be extremely expensive.

There are other products that you can use on problem gypsum/cement based products

eg owatrol EB

http://www.igoemailorder.co.uk/v2/i...ategory_id=16&option=com_virtuemart&Itemid=71

Peeling on dry plaster is often however a function of suction (excessive absorbancy). That is why you need to thin the first coat- otherwise the paint dries too quickly and fails to soak in properly- then leading to peeling.

 

[opps]

So I can use e.g. Dulux Trade Vinyl Matt directly onto new artex with no problems as long as the first 1 or 2 coats are watered down?

There's no problem using a high vinyl-content paint on new artex?

Ok- so long as the artex is really dry

 

[Growler]

Dulux trade supermatt can be used on plaster/artex that's still drying out.
This does not mean that you can put a vinyl over this and then expect it to be good if the original surface isn't yet dry.

You can use Dulux trade vinyl matt on new plaster as long as it's snuff dry.

You cannot use Dulux rich matt/silk over new plaster, without sealing it first and it must be dry before you seal it.