I just installed a new plasterboard ceiling (phew - that was a
challenge!). I'm now going to do some jointing and have a few questions

for those more experienced than I....

1) I'm going to use Gyproc Joint Cement. Is this OK as a finish (i.e.

I don't need any additional finish layer on top)?


2) I recently did a little bit of patching up on a wall. At the
joints I used joint tape (the paper kind). It seemed okay. A builder
friend told me to use self-adhesive scrim tape on the ceiling. Which
should I use - paper tape or scrim?


3) When I did the wall, I found it really difficult to get a smooth
result over the joints. I sanded by hand as much as I could but the
dried-on joint cement always had an edge to it which is still visible.
How can I avoid this on the ceiling? Should I spread the joint cement
differently? (I'm using the Gyproc guide as a basis). Should I use a
power sander to get a better result? what sort of abrasive paper would
be best suited??


As always any advice most welcome and appreciated.


Scott.

Tony wrote:
1) I'm going to use Gyproc Joint Cement. Is this OK as a finish (i.e.
I don't need any additional finish layer on top)?

Yup.


2) Which should I use - paper tape or scrim?

Scrim.


3) When I did the wall, I found it really difficult to get a smooth
result over the joints. I sanded by hand as much as I could but the
dried-on joint cement always had an edge to it which is still visible.
How can I avoid this on the ceiling?

Use a flat wide tool, don't overfill.


Should I spread the joint cement
differently? (I'm using the Gyproc guide as a basis). Should I use a
power sander to get a better result? what sort of abrasive paper would
be best suited??

Use a wide flat hand sander. Make sure the filler is really dry.

"Tony" wrote in message
oups.com...
I just installed a new plasterboard ceiling (phew - that was a
challenge!). I'm now going to do some jointing and have a few questions

for those more experienced than I....

1) I'm going to use Gyproc Joint Cement. Is this OK as a finish (i.e.

I don't need any additional finish layer on top)?


2) I recently did a little bit of patching up on a wall. At the
joints I used joint tape (the paper kind). It seemed okay. A builder
friend told me to use self-adhesive scrim tape on the ceiling. Which
should I use - paper tape or scrim?


3) When I did the wall, I found it really difficult to get a smooth
result over the joints. I sanded by hand as much as I could but the
dried-on joint cement always had an edge to it which is still visible.
How can I avoid this on the ceiling? Should I spread the joint cement
differently? (I'm using the Gyproc guide as a basis). Should I use a
power sander to get a better result? what sort of abrasive paper would
be best suited??


After having just done my kitchen ceiling this weekend (+3 helpers as used
15mm soundbloc, heavy.......) my advice is, use the ready mixed Gyproc (£11
B&Q), I find it has much superior properties than mix your own, use self
adhesive cloth scrim for speed, after second filling of joints (use a proper
wide metal Marshaltown dry joint filler), let dry, sand vigorsously till
"quite good and flat" and paint with a "mist coat" of matt emulsion (very
wet mix, about 2 water: 1 paint or more).

This coat serves two purposes, enables you to see the "edges" and holes
easier and stops the ready mix filler being sucked dry by the board/filler
enabling you to fine fill the "edges" easily. After this sand again and mist
coat any exposed filler and board. Do not use a power sander, will create
undulations, I used a pole and hand sander with 80 grade paper. Keep doing
this fill, sand and mist until happily flat or your arms are knackered .
Then paint with lightly diluted matt (10-30% water) for first coat, as it is
still lightly absorbant. Finally final matt paint, use Dulux Trade matt (yes
its more expensive at £17/5l compared to £9/5l normal matt) but it is
thicker so it is done it just one final coat and being thicker fills all
those tiny edges, holes, scrapes and other imperfections you missed in all
the a*sing around filling, sanding and misting.

Also using a bright 150W spot light at head height (or the halogen spots
dangling from their wires) looking along the ceiling enables all the little
imperfections to be seen. Be carefull, it reveals all !!!!, even things that
won't be seen by people not having a 150W spot and head on the ceiling when
in the room!!!. I once saw a decorator who had a 12V halogen spot and
trasformer bolted on short length of wood doing just this to spot
"imperfection".

Ceiling (all 25sq m) went up Saturday and tonight will be putting the
halogen spots back in the ceiling tonight, job done.

The best board to use if you are not going to skim the whole ceiling is the
taper edge stuff. You get a good finish with the scrim and filler. With flat
edge board, you have to be really good not to show a hump at the joints.

ken

On Wed, 26 Apr 2006 18:03:25 +0100, "Ken"
wrote:

The best board to use if you are not going to skim the whole ceiling is the
taper edge stuff. You get a good finish with the scrim and filler. With flat
edge board, you have to be really good not to show a hump at the joints.

ken


I will probably have a short join where the ends of two pieces butt together .

Is it likely to be more successful if I taper the edges at that join...maybe use
a small plane or somesuch ..it'll be a join of about 12-14"


Stuart

Ken wrote:
The best board to use if you are not going to skim the whole ceiling is the
taper edge stuff. You get a good finish with the scrim and filler.

IMO that's the only sort to use. if you're not skimming. The "bumps"
always show to some extent.

Thanks for all the advice. I'm going to use self-adhesive scrim tape
and gyproc joint cement applied with a 6" metal jointing knife. I also
got a pole sander and some 80 grit paper.

I used tapered edge boards, but will have problems where the boards
meet on the untapered edges (the short edges top and bottom). I'm just
going to do my best there.

I did the job a week ago as described above and have since sanded,
primed, painted and cutout spotlights. I have to say it looks bloody
brilliant. It's the smoothest ceiling in the house, and repeated
filling, sanding, sanding again and more sanding really makes all the
difference.

In the end I used three (or maybe even four) coats of primer (because I
had some much and didn't want to waste it) and I think this had
something to do with the final result. I also applied about three coats
of white paint which again covers any fine imperfections.

With spotlights in place pointing downwards, the focus and attention is
drawn away from the ceiling anyway and any remaining imperfections are
not at all noticeable.

I did need to fit coving to cover up the gaps around the edges of the
ceiling, but otherwise job done.

Thanks for all your help.