Filling cracks and gaps before painting - help

[b4drad]

Hi,

I need to re paint the whole of my house - some of which has had professional work so is fine and other rooms that are as brought. There are occasional cracks on walls/ceilings. most small but some a couple of cm (where plaster has come loose).

I was told by a plasterer that I should use silicone for the cracks as poly filla would just recrack. Reading online there is also Caulk...Not sure of difference. So my questions are:

1) to make good the old walls with small cracks do i use silicone (which?) or caulk (which?)?

2) I i need to make crack bigger to get a good fill?

3) do I need to prime these with pva / plaster paint before painting?

4) for rest of house plastered by professionals do I prep with watered down paint (50:50), watered down PVA (what mix), or just get dulux plaster sealant?

Cheers all.

H

 

[Robbie uk]

1/ Don't use silicon on the walls or you paint won't stick, use a decent caulk as long as the crack isn't too wide or deep.

2/ Sometimes it is better to rake out a crack so that the filler has something to grip to

3/ Never put PVA on a wall that you intend to paint or you will have problems later.

4/ On raw plaster or anywhere that you have filled a thinned down coat of matt emulsion is needed to act as a base coat prior to the finishing coats. 30 % dilution is all that is needed.

5/ Don't listen to plasterers giving decorating advice..