How to prepare dusty Walls and floor

[fosbie]

I've got a dusty brick garage that I'm trying to tidy up with a new lick of emulsion paint on the walls and some floor paint on the concrete floor.  The dust on the walls is mainly brick dust from building work that we've had done, but the concrete floor has always been dusty. 
 
Whats the best way to prepare the walls and floors before painting?  Should I just paint a coat of PVA / water mixture onto everything beforehand?  I think the floor paint I've got says it seals as well so maybe this will be alright on it's own.

 

[TheDec]

Whatever you do don't use pva.

Dec

 

[fosbie]

Whatever you do don't use pva.

Dec

Why not?

 

[TheDec]

Because your paint will not stick to it, give it a good brush down with a stiff bristle brush and seal the walls with a coat of thinned emulsion, and just follow the instructions with regards to the thinning of your floor paint.

Dec

 

[fosbie]

Is that also the best way to paint a newly plastered wall? I always though it should be sealed first.

 

[TheDec]

Yes you should use a thinned emulsion to seal plaster skim, and a matt emulsion is the
better choice, on no account ever use PVA.

Dec