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amiller73 12-08-2005 08:15 AM

Painting disaster - help!
 
We have painted a number of rooms in my house with few problems, but have now come to painting my son's room. All the rooms have been freshly plastered before painting and previously we have sealed the plaster with PVA and then applied two coats of dulux paint.

A number of workmen who have worked on my house, however, have advised us not to use PVA and instead to use a coat of watered down white paint (50-50) before applying the two coats of normal paint. This is what we tried on my son's room, therefore. We painted the ceiling with few problems, but we have encountered an odd problem with the walls.

We used B&Q paint in my son's room as we wanted to use "Real life" paint for its washability and resilience and the B&Q range did the colour we wanted. The first coat we applied looked fine - slightly patchy but only what you would expect for a first coat. The second coat looked even patchier. We applied a third coat to one wall last night and this is the worst. It is very patchy in terms of light and dark patches and also you can see where we have painted in sections which have slightly overlapped.

Can anyone explain why this has happened? Is it the paint or the fact we have not PVA'd?? Should we PVA now and apply a new coat of the same paint? Or should we just buy new dulux paint and put a coat of this over the top? Should we sand it down before doing either of these (my boyfriend thinks we may have a build up of paint in certain areas??)

We are now on a tight deadline for getting this finished before Christmas and don't know what to do. Please help!

Teetorbilt 12-08-2005 09:44 AM

I'm thinking that the 50/50 was a bad idea and that the plaster is still soaking up paint like a sponge.

I'd apply one of these http://www.zinsser.com/ primers, you can have them tinted close to your wall color and possibly straighten everything out in 2 coats (1 primer & 1 topcoat).

r0ckd 01-12-2006 02:23 AM

If I understand the problem correctly, these patchy parts are roller marks.

You may not be using the "wet edge". You must always you the wet edge of the paint. You have to work quickly and cannot go over what you've painted if you've painted it more that a minute or two ago. What happens is what is called "dragging", this happens mostly when brushing paint. However, this can happen with a roller as well. "Dragging" is painting over paint that isn't fully dried or paint that has been drying for more than a minute or so it causes these marks. When you cause dragging, it will look like the color of the paint has been changed, but in actuality the texture of the paint has been changed. This will cause the light to refract off the paint and create the illusion of the paint being a different color.

To prevent "dragging", you can use these following processes:
1. Always use the "wet edge"
2. Always paint in vertical strips, never paint spuratically
3. Do not paint the upper half of the wall, then paint the lower half. It must be painted from floor to ceiling at the same time.
4. You can also try to control the temperature and humidity of the room that you're painting. The colder and more humid you can get the room, the more time you have to work with the paint without "dragging"
5. There is also a product called "FloTrol". It's a latex paint conditioner that slows the drying time.


Hope this helps,
Dan


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