I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he
http://www.makewrite.demon.co.uk/GasFittingStandards

On Fri, 11 Aug 2006 22:11:19 +0100, Ed Sirett
wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Was the concrete/plaster new? If so it's alkalinity could have caused
the peeling. Also caustic strippers would have the same effect.

Maybe worth trying an alkali resistant paint/primer/sealer. Eg:

http://www.decoratingdirect.co.uk/viewprod/t/TORARP/

Or could the ceiling be painted with distemper? This is too powdery to
paint over and needs sealing with PVA or stablilising solution.

cheers,
Pete.

Ed Sirett wrote:
I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Tha cause is lack of sufficient adhesion, but that has more than one
possible cause. Eg dirt or grease on the ceiling, or a glossy oil
painted surface. Also emulsion will come off under the influence of
some detergent type things, especially ecover. I'd try a thorough
surface wash, and maybe a very quick run over with a fine sander to
ensure a good key. If all else fails there are problem primers, but I
prefer to avoid them as theyre bulky, and usually unnecessary time and
expense.


NT

wrote:
Ed Sirett wrote:
I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Tha cause is lack of sufficient adhesion, but that has more than one
possible cause. Eg dirt or grease on the ceiling, or a glossy oil
painted surface. Also emulsion will come off under the influence of
some detergent type things, especially ecover. I'd try a thorough
surface wash, and maybe a very quick run over with a fine sander to
ensure a good key. If all else fails there are problem primers, but I
prefer to avoid them as theyre bulky, and usually unnecessary time and
expense.


NT


Dulux often does this IME.

On Fri, 11 Aug 2006 21:11:19 UTC, Ed Sirett
wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

Classic reason is that it's been distempered. I speak from bitter
experience...

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

On Fri, 11 Aug 2006 22:11:19 +0100, Ed Sirett wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Thanks for the help guys.
The ceiling was old and covered with black mould. So I scrubbed it with an
anti-fungal wash. Then I painted it with two coats of matt vinyl emulsion
(which was a specialist antifungal paint - McPhersons IIRC).

Reading your posts it looks like I might have left alkaline deposits
(cleaning materials) on the surface.

Anyway to cure (when the time comes - the tenant is OK about it ATM) looks
like:
1) Scrape all loose and flaking off.
2) Scrub with plain water.
3) Lightly sand.
4) Rinse down with water again.
5) Oil based Alkali resisting primer.
6) Two coats of bog standard vinyl matt emulsion.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

Ed Sirett wrote:
On Fri, 11 Aug 2006 22:11:19 +0100, Ed Sirett wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Thanks for the help guys.
The ceiling was old and covered with black mould. So I scrubbed it with an
anti-fungal wash. Then I painted it with two coats of matt vinyl emulsion
(which was a specialist antifungal paint - McPhersons IIRC).

Reading your posts it looks like I might have left alkaline deposits
(cleaning materials) on the surface.

Anyway to cure (when the time comes - the tenant is OK about it ATM) looks
like:
1) Scrape all loose and flaking off.
2) Scrub with plain water.
3) Lightly sand.
4) Rinse down with water again.
5) Oil based Alkali resisting primer.
6) Two coats of bog standard vinyl matt emulsion.


What's a CORGI doing buggering about with all this? I thought you guys
had more lucrative things to do :-)

On Mon, 14 Aug 2006 08:59:22 +0000, Stuart Noble wrote:

Ed Sirett wrote:
On Fri, 11 Aug 2006 22:11:19 +0100, Ed Sirett wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Thanks for the help guys.
The ceiling was old and covered with black mould. So I scrubbed it with an
anti-fungal wash. Then I painted it with two coats of matt vinyl emulsion
(which was a specialist antifungal paint - McPhersons IIRC).

Reading your posts it looks like I might have left alkaline deposits
(cleaning materials) on the surface.

Anyway to cure (when the time comes - the tenant is OK about it ATM) looks
like:
1) Scrape all loose and flaking off.
2) Scrub with plain water.
3) Lightly sand.
4) Rinse down with water again.
5) Oil based Alkali resisting primer.
6) Two coats of bog standard vinyl matt emulsion.


What's a CORGI doing buggering about with all this? I thought you guys
had more lucrative things to do :-)

My core job is to run several flats both for myself and others. In fact
the CORGI thing was more a matter of necessity (some years ago) when my
erstwhile trusted gas fitter retired. I could not find anyone to do
the job that wo0uld answer my calls. I guess, it's a pretty sound business
policy that if you can't find someone to do something then you should
start a business doing it for yourself and offering the service to others.

Indeed I could fill up all all day everyday for the rest of my (somewhat
shortened) life doing gas and heating but that isn't the target.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

On Sun, 13 Aug 2006 22:15:57 +0100, Ed Sirett
wrote:

On Fri, 11 Aug 2006 22:11:19 +0100, Ed Sirett wrote:

I painted a concrete/plaster ceiling last year with do coats of white
matt emulsion. This year it has curled up and flaked off.

What did I do wrong?
The location is a bathroom with a shower?

Thanks for the help guys.
The ceiling was old and covered with black mould. So I scrubbed it with an
anti-fungal wash. Then I painted it with two coats of matt vinyl emulsion
(which was a specialist antifungal paint - McPhersons IIRC).

Maybe the paint wasn't suitable for high humidity areas, could be
worth a quick call to them to check.

Reading your posts it looks like I might have left alkaline deposits
(cleaning materials) on the surface.

Anyway to cure (when the time comes - the tenant is OK about it ATM)

A friends bathroom ceiling has been like this for some years... it's a
flat in a fairly old block again with concrete/plaster ceiling.

looks
like:
1) Scrape all loose and flaking off.
2) Scrub with plain water.
3) Lightly sand.
4) Rinse down with water again.
5) Oil based Alkali resisting primer.
6) Two coats of bog standard vinyl matt emulsion.

I'd tend to agree, if the old paint continues to peel, it's not worth
overcoating with something expensive.

Even so, a bathroom paint should be more resistant to humidity, you
don't want the new paint to peel off the above.

Also check it's OK over oil based, might need keying with a paint prep
pad.

Still, if mildew reoccurs, it might be worth using mildew resistant
bathroom paint, eg:

http://www.decoratingdirect.co.uk/viewprod/z/ZINPWBP/

I'm sure I've seen a Dulux version much cheaper tho.

cheers,
Pete.