Messy ceiling

[chriselevate]

Hi,

I've got a ceiling that's in a real mess where it's slightly bulging in places, got joins, and generally a mess!

I'm planning to re-plasterboard it as this will be a heck of a lot easier for me to plaster and was wanting advice for how you would board the old stuff?

Is there any advantage of trying to get some insulation trapped between the old plasterboard and the new stuff and how would this be done if it's worth it? (I have lagging in the loft so this is helping heat loss but as it's a solid construction house added insulation is always appreciated!)

Thanks

 

[mointainwalker]

Is there any advantage of trying to get some insulation trapped between the old plasterboard and the new stuff

Absolutely not. Crazy idea.

Take down the old plaster-board and renew, otherwise how do you hope to get it flat if you are following contours of the old bulging stuff ?

Add more insulation if required.

 

[chriselevate]

Thanks for your quick reply - appreciate it so much.

Ahhh right, easiest was would be to rip down the old stuff and put new up? This will be VERY messy I guess but the best way of doing it?

Isn't it a good idea to batton off the old and the screw to this or this a lot of hassle to do?

I agree with you about the insulation.... crazy idea I guess!!!

Thanks

 

[roughcaster]

I'd agree with M/Walker. Either take down the old plasterboard, straighten the underside of any twisted /bent joists and re-board,(awkward, messy),,
or,, construct a new straight/flat ceiling just below the existing,,, which is what i would do,, very little mess either. Once it's done, tape it all up and skim.

 

[chriselevate]

Construct a new one just below? By using battons screwed through then and into the joist and the plasterboard onto the new battons?

Or how would you get a fix 8 x 4 on the original ceiling?

I favour this option as if I remove the ceiling a couple of the Walls I've already plastered will need doing again as the new boards won't cover the marks left on the walls.

Thanks

 

[BBSBuilding]

Taking the ceiling down is the best job but to need to weigh up the pro's and con's.
If the ceiling is not too uneven then you could board over.
- Use long dry lining plaster-board screws.
you will need to locate the joists on both sides of the room and draw a line between them.
I do this by drilling holes....you'll know when you've hit a joist.
Pulling down ceiling, especially lathe and plaster is normally extremely dusty and you will be cleaning up ages.
I have pulled down ceilings and not been able to see my hand in front of my face. You will need a good quality dust mask also.
In my opinion....only pull it down if you have to.
As far as insulation is concerned. if there is a loft above then just add to it.
If not you could use thermal board - polystyrene backed.

 

[chriselevate]

Thanks for the reply, really appreciate it.

I think I'll go with the overboarding as the ceiling isn't awful it's just rough. What thickness plasterboard would you use? You'd go for tapered edges I guess?

Every joist there is you'd screw the PB to it? What do you do where the PB ends and there's nothing screw it to where they join? Does this not matter as the joists are relatively close together?

Thanks

 

[BBSBuilding]

For best results you would cut the boards to the joists once you know where they are.
I have in the past just butted them and put in a dry-lining screw through the board above at an angle.
The scrim will hold it strong once the plaster has gone off.
All joints and edges need to have scrim tape over them otherwise they will crack.
If you've never plastered before you should test on a small wall.
It takes a lot of practice to learn plastering!!

 

[roughcaster]

For best results you would cut the boards to the joists once you know where they are.
I have in the past just butted them and put in a dry-lining screw through the board above at an angle.
The scrim will hold it strong once the plaster has gone off.
All joints and edges need to have scrim tape over them otherwise they will crack.
If you've never plastered before you should test on a small wall.
It takes a lot of practice to learn plastering!!

Another thing you could do to save you cutting the sheet/s if the sheet lands between the joists, is to put a bead of "sticks like sh*t" or similar, along the end of the sheet, plus the angled screws.
I've seen joiners reboard over a ceiling and put a bead of "sticks like sh*t"" all around the perimeter of the room,, but screw fixing into timber joists along the way, as and when they line up.

 

[chriselevate]

Thanks both of you.... you've both been really generous with your help and I really appreciate it.

Don't panic too much, I'm an ok plasterer, but have only plastered my own walls - people are amazed at what I can do with my marshall town trowel though! I went on a 2 day course and paid a fortune but as I don't do it very often I lose the confidence and especially when there's a tricky situation coming up (like the messy ceiling) I like to get advice first.

I think a really skilled plasterer could possibly take out the bumps with bonding and then skim the whole lot but I'd much rather plaster onto new plasterboards to make it easier for me. I'll do as you've suggested and dry wall screw through all the board and into the joists and then use some adhesive at the joints with an angled srew if needs be.

The only thing I'm not going to be able to tape up are the edges that meet some of the walls as I've already plastered them. I'll try to make sure that I get the board to fit snug up against these walls so I don't have much of a gap.

I'm guessing I should go for the 10mm plasterboard as this will help reduce the weight of the boards to be put up? Or is it best going for the thicker stuff so it handle the bumps in the exisiting ceiling a bit better?

As it's a large ceiling (and I'm not a lover of ceiling plastering!!!) I'll be using stop beads so I can do it in 2 sections. That way I can take my time plastering it rather than rusing to get my second coat on and then trowlling it off etc!

 

[BBSBuilding]

yes 12 mm would be better for feathering out bumps but i think id still use 9mm and let the plaster take out the bumps.
Probably need 3 coats.
No real need to use stop bead though.
just stop half way and feather the edge as thin a possible into the plaster board. When plastering the other side apply 2 coats of watered down PVA to the plasters edge to prevent it drying to quickly.
You will need to feather this joint by trowling and brushing with a wet paint brush....spend some time here and you should get it more or less perfect.
A light rub with sand paper helps when dry too.
You should scrim the edges but just lap it only very slightly over the adjacent wall, double it up to cover large gaps.
another tip...working off steps is difficult on large areas.....staging of some kind will make it easier.