Brissiewoman

The walls must be sealed before painting. Once you have settled on the paint you are going to use find out what the appropriate undercoat and sealer is for the paint type. Your paint shop should be able to help as will reading the instructions which should contain the details you are after. The company will have spec sheets etc on their website as well.

Ive talked to few painters while working on new houses - as you do when you are all under the one roof - and they just water down the first coat ( called a "piss coat" - there term not mine ) and spray it on, then go over with two top coats of the same paint with no thinning, back rolling the final coat for texture. Most paints that Ive seen and bought recently are primer/sealer/top coat in one.

.....possibly the same guys who would never dream about using a tack rag on anything......

Thanks to all of you for advice...

Tack rag ?

I would apply a coat of acrylic sealer undercoat on before applying any top coats. Then pole sand the sealer once completely dry removing any humps, bumps and grit that had surfaced. Then apply top coats.

I'm not a painter but have painted plenty of houses and find if walls aren't sealed first then the plaster joints always look a little flat even after 2 topcoats. I always use a sealer/undercoat despite nowdays paint saying it is all in one.

Agree.

Still want to know what a tack rag is though

A tack rag is for picking up fine particles of dust, its the equivalent of a lint roller but with a little bit of varnish soaked into the cloth , gives a super smooth finish ! I have never used it on walls but on tables etc.!

Ummm, what ? you rub painted walls with a rag soaked with varnish to pick up dust ? I better google it

Ok, googled it - all clear now, used in furniture refinishing, not for walls. Sounds pretty good actually, I normally just used compressed air

Used on dusty material such as plaster after sanding etc. Works a little better than just giving it a blow job. Can get away without it - but more important for a good finish on architraves after sanding or refinishing.

Can buy them is little packs from "better" paint shops. I am anal retentive and a coat of paint is not good enough for me - do it once do it properly.

"Works a little better than just giving it a blow job"

Theres something I'd like to see