A property I need to do some work in has water stains on some walls, from penetrating damp (failed pointing). I have sorted the pointing and now want to touch up the emulsion on the effected areas indoors.
Should I use a stain block paint first? Will something like Johnsons Alkali Resisting paint work? Should I just touch up with emulsion and hope the stain does not bleed through?
Ta,

Ta, I will keep an eye out for it.

woodsmith wrote on Aug 4^th, 2009, 7:25pm:

'Use with all paints' it say's on the tin. I painted it on a new wall in the bathroom & overpainted it with Dulux b'room paint.
It can also be used as knotting, which is nice as it's white!

Really if you must paint matt emulsion over silk it's best to really rub down the silk to provide a 'key'.

Putting flat paint over shiny paint is not too good, shiny over matt, not so bad.

What's all this about 'gloss emulsion' Woody, it's a new one on me.  

Quote:



And the reason I was using it in the first place, was that the bathroom paint peeled off! It was like wallpaper, I've never seen anything like it in my life.
The walls had had a fresh skim (2 coats) of plaster about 2 or 3 weeks prior, then a VERY wet & messy mist coat with about 20-25% water added as it was very hot at the time. Next a coat that was probably about 10% thinned, then a finish straight from the tin. The paint was ICI/Dulux Bathroom paint (with the little yellow duck on it), which I have used loads of times before.
After the tiling (I painted before the tiling as the mist coat is so messy) I taped over the plastic edging & a bit of wall with masking tape to keep it clean from grout. As soon as the grouting was finished I removed the masking tape..........and most of the paint! I had sheets of it hanging over the shower door!
I contacted the ICI/Dulux Customer Advice Centre & spoke with  a very helpful young lady who asked me to send in a sample.
Today I got the feedback that it was nothing to do with the paint, but as a goodwill measure they would compensate me with 5l of a paint of my choice.
I'm more than happy with the the result, but am curious as to what others would have done for priming / mist coat?

I think I would have done the same as you TB.
You waited two or three weeks for the plaster to dry out, no problem there.

You thinned the mist coat well so it would sink into the plaster, OK.
Subsequent coats, OK.

I would hazard a guess that when the paint came away from the plaster that it came clean away and left the original bare plaster, ie, the mist coat came off as well.

If that is the case it suggests to me that the plasterer has shone the plaster up to a hard finish and as thin as it was, the mist coat just sat on the top rather than soaked in.

Paint's OK.  Your painting's OK.

Find the plasterer and kill him.

Over-skimming can cause your problems, TB. By that I mean the plasterer going over and over and over the final skim layer.

Give the walls a rub with some sandpaper, wipe off the dust and start again...