primer, pva sealer for new house

R

rdeasy

Guest
Can someone recommend a pre-paint procedure for painting a new house that has a smooth gyproc finish.

what exact products and/or sealers if any are the best to use, and links would be helpfull,

Thanks,
 
Inside -- Normally a very diluted paint and water as new plasterboard absords it.
Outside -- You can mix a bit of Pva with an external paint but not neccessary.
 
Inside as said dilluted paint ...cheap trade white for a mist coat, then your quality colurs. (An imperative necessity)
Externally never use pva in any circumstances, (breathing of walls not being one of the reasons not to use though)
 
yes, its for internal walls, anyone ever heard of people using pollyfilla and water on new internal gyproc plastered walls before painting

Thanks,
r.
 
dont use watered down paint,get some acrylic primer sealer for your first coat especially on block walls,this stops mapping.
 
Could someone please clarify just why PVAing is such a bad idea. I am particularly concerned with disadvantages of PVA for internal plastered walls, if there are any?
 
Jab1,
Any idea on what causes mapping? Had it in my own house in nearly every room few years back.
 
Hacker, how did you solve the mapping problem. Just keep applying more coats or should I do something else??
 
rmdt,
The worst thing you can do is keep applying more coats, this is what I did!!! I ended up getting a mouse sander and sanding all the paint off the wall as the mapping kept coming thru. A truly horrible job. I sanded all the walls that had mapping on them it was the only way I could get around it. If you want to test the plaster to see if it has mapping get a v wet cloth and wipe the wall with it, and if it comes up as if it has oily patches thats mapping. I dont know what causes it and the plasterer at the time said give the walls a light sanding but a light sanding didnt do it, I ran the mouse sander over all the walls. Still dont know the cause of it, was told over troweling, too smooth a finish. Tried PVA and that didnt work either. Have seen it in another house since, different plasterer though.
 
IMO, no expert, just a victim.
If mapping happens you will see it straight away when you apply the first or mist coat to newly plastered walls. It is as if there is an oily film on the wall and the paint won’t stick to it. The word mapping comes from (I think), the patches that take the paint as normal and patches that are affected and you end up with shapes that look like islands on a map. No amount of paint will get rid of this and the paint will eventually flake off the affected area. I sanded the walls and this got rid of it. note: my house was block build, dont know if it happens on plaster board.
 
In our house one of the walls was polished by the plasterer at my request. I just wanted to see a very shiny finish. He advised me against it but I went ahead. Beautiful to look at but the painter had an awful job. The rest of the rooms were painted as normal but the polished wall had to be sanded and re-skimmed after these patches appeared. I assume that the polishing was the problem.
 
I encountered the same mapping issue. In reply to hacker, the issue does not happen on Plasterboard / Dry lined walls only block work. I overcame the problem by allowing first coat of paint to completely dry out ie 2 weeks between coats and the 2nd and 3rd coat seems to have overcome the mapping issue