Cornice Cement or Wet Area Compound

Welcome to the forums Matt

I'm no expert but as a chippy I've done a lot of plastering jobs, and as far as I'm concerned they're interchangeable. I've used cornice as base, and base as cornice.
I think cornice cement goes off a bit quicker, and has a better initial grab, so you can push a cornice into place and it will stay there after holding it in place for a few less seconds, but I've used base before and I haven't had any call backs.

For a small job, rather than buying two products, I'd just get a 20kg of cornice and use it for everything. You can put a bit of citric acid (lemon juice or orange juice) in it to slow it down, or as our resident expert Rod has told me, you can use salt to speed it up.

He'll probably be along shortly, and he'd have all the right information on this one I'd say. I'm interested myself.

I would not use basecoat to put up cornice any time. In the years I have been plastering I have never used base coat to put up cornice. Pawn head is right about the initial grab etc. and once it has set it may well stay in place without cracking, personally I would not use it.

As pawnhead says the best oprion is to get cornice adhesive and use it for the whole job.

Cheers Rod

There you go.
I'll know better next time, although I did whack a few clouts in them as well, and I'm sure they're still up there as we speak.

But then again, I like fibreglass tape as well, and that's a bit of a no no around here.

I would go with the cornice cement any time as I would assume it is much easier to use.

I bought some of that Gyprock Wet Area base coat and used it for my bathroom joins. Personally I hate all of the ready mixed base and top coats I have bought. They shrink amazingly (especially the top coat). Also the base coat dries very hard and will be difficult to remove excess if it dries. It does not sand well at all. Cornice cement, on the other hand, can be easily sanded down.

Originally Posted by Gooner

Cornice cement, on the other hand, can be easily sanded down.

Yeh, that's all I use most of the time. Forget about the topcoat, and just put three coats of cornice on. Top coat is softer, and more hassle to apply I reckon, but it is easier to feather the edges.