Skim coating - help required.

[Firkin]

Hi guys, wee while since I posted last

1.
I'm preparing a room for plastering (Skim coat) and the room is already boarded out and taped at the joints. Do I need to use PVA or not? Reading through the posts here it seems there are two camps of opinion but none that seems definitive. Should I PVA or not before skimming

I've already tried skimming the face of a 4 foot wide projecting part of the wall on the dry board and the skim coat (Thistle board finish) appears to have stuck really well to it. It isn't 100% dry yet so when it is I should know if okay or not.

2.
Do you folks recommend using a derby or just working with the trowel on its own?

Look forward to your responses.

Firkin

 

[roughcaster]

I've never used PVA on new plasterboard,whether it was onto the big sheets, or onto the small sheets of plasterboard lath, and plasterer's that I've worked with in the past never did either...... As regards to using a darby for skimming.... no, just use the trowel. The darby is a great bit of kit, but is used more for thicker floating/render coats.

Roughcaster.

 

[roy c]

I tend to scrim- tape all my joints first with skim or adhesive and if I have to leave them for a few days before getting around to skimming them I brush them over with unibond before I start skimming. Sometimes if i am going on to an "old wall" I will put a straight edge over it to see if there are any high or low spots and then get an idea if it needs straightening a bit,,,, I find by doing the joints first you don't have to put too much more skim on the tapers when skimming the lot...

 

[Richard C]

I'm preparing a room for plastering (Skim coat) and the room is already boarded out and taped at the joints. Do I need to use PVA or not?

PVA is not normally used on new boards as they are classed as low suction; but if you’re still learning & need a bit more time on larger areas, it won’t do any harm!

If you’ve made your stud well so adjoining boards are true & flat, the thin skim coats will (should!) be self levelling if you’ve mastered your trowel action; Derby is really for levelling much thicker float/render backgrounds as already stated.

,,,, I find by doing the joints first you don't have to put too much more skim on the tapers when skimming the lot...

Why use taper edge boards if you’re going to skim? That’s what square edge boards are for, saves all that messing about!

 

[joe-90]

The important thing is that the ivory side is face out. You shouldn't be able to see any writing on the boards. If that's so - then no PVA required.

 

[Richard C]

You shouldn't be able to see any writing on the boards.

Which quiet thoughtfully says "plaster other side"!

 

[roy c]

Where I live and work you can't get "Square edged" Boards!!!All our boards are "Tapered edged"It makes for a better job and guaranteed no "hairline" cracks. Its no trouble!!!!

 

[joe-90]

You shouldn't be able to see any writing on the boards.

Which quiet thoughtfully says "plaster other side"!

If you are wallpapering direct - then you use the side with the writing on.

 

[Richard C]

Where I live and work you can't get "Square edged" Boards!!!

Blimey; where the hell is that then As for hairline crack's on square edge boards; properly supported & taped they are no problem; I've never had one!

 

[Firkin]

Thanks for all the replies folks

I've skimmed straight on to the board and so far it is sticking like glue Need to touch up a few bits here and there but overall I surprised myself

Used way too much water and plaster mix for the area I wanted to cover which - I seem to recall - was a problem when I tried plastering before. Ah well better too much than not enough.

Thanks guys