Painting straight over plasterboard ceiling.

[geoffishere]

I am replacing a ceiling in a bedroom. The need for this was a leak which has fixed bowing the existing plasterboard. I have plasterboard a few ceilings but have always had them skimmed and have just filled in the gaps/joints with filler. However from reading articles on the web, if the job has been done well i can just paint over this using water downed matt paint.

Firstly i wanted to check, is this correct??

and secondly it talks about taping the joints, do i need to do this or is filler enough??

Many thanks

 

[roughcaster]

Hi Geoff,
If you don't put tape over the joints in the p/board and just flush them off with filler, you will get cracks in the ceiling along the joints. Always tape the joints especially in rooms in your house.... So with a trowel or a taping knife, put the tapes over the joints,(paper tape or self adhesive mesh tape), cover the tapes with filler, flush them off with Gyproc joint finish, (ready mix), when dry, sand down and you're ready to mist coat and then emulsion..... I would go for self adhesive mesh tape if I were you.

Roughcaster.

 

[geoffishere]

cheers for that.

Do i fill the gap in between the boards before i tape or do i just tape then fill on top of the tape. Are these joints visible one sanded and painted. Is the finnish any worse than if skimmed then painted

Cheers

 

[roughcaster]

If you use self adhesive "mesh tape", stick that over the joint/s first and then cover over the tape with Gyproc Joint filler to bring the joint flush with the surface of the plasterboard. Let it all set and dry. Next day, you would then put on a coat of Gyproc joint finish over each joint. This comes in a tub as a creamy ready mix, that gives a smooth finish to the joints, all they need when dry (day after), is a light sand down with a "very" fine sandpaper. To be honest,nearly all joints in plasterboard done this way are visible once sanded and painted if you look closely enough or the light shines across them, but some people are better than others at doing the job. Speaking as a plasterer,there is no comparison between a well skimmed plasterboard wall, and a well taped plasterboard wall.......

If you use "paper" tape on the joints in the plasterboard, you will need to put on a layer of filler down the joints first, and then bed the paper tape into it, making sure it is well bedded, remove the excess with the scraper/trowel and make sure there are no air bubbles under the tape. Let that set, and then flush of the joint with more filler. After that, go over it with the ready mix etc as mentioned above. Alway go out a few inches (3 or 4 ish) either side of each joint to feather away edges.... This is the rough basics of Taping, but as with most trades/skills, there is a lot more to it.

Roughcaster.

 

[kilo_4que]

geoff, what you need to do is something called tape joining. As roughcaster has said, you need to tape the joints with drywall tape and then neatly a coat of joint filler or easi fill (easier to use). Once it dries you can give it a light rub down and then add a top coat i.e. a second coat. This would need rubbing down and feathering in with some fine grit paper.

Once done, add a mist coat followed by two neat coats or two mist coats followed by a single neat coat.