Repair or cover bathroom ceiling?

[acmedone]

The existing bathroom ceiling is plasterboard covered in lumpy paint applied with roller (maybe artex) with a repair patch (1'x1') over where I removed some boxwork. Jointing tape is peeling in parts. Apart from the cosmetic finish the ceiling is basically level and in good condition.

I thought I would try and level it out using one of those DIY smoothing products after knocking bigger lumps off and cleaning with sugar soap. First attempt over a couple of square feet gives terrible result because there are patches where it just doesn't stick when smoothed over.

Questions.
1) Is there a preparation that might get it to stick? Even then, is this exercise basically futile anyway?
2) Would a plasterer attempt to skim it?
3) Should overboarding & skim be considered? 3 pieces of 1800*900 will cover it.

On the 3rd point, I think the new plasterboard can go snug to the existing without battens. Correct? (Battens at 450 intervals are already in place between rafters and existing board. Obviously screws need to reach into the rafters to take the weight.)

 

[Richard C]

1) Is there a preparation that might get it to stick? Even then, is this exercise basically futile anyway?

It’s god awful stuff, chuck it in the nearest skip

2) Would a plasterer attempt to skim it?

I you’ve got patches of that god awful stuff that hasn’t stuck properly then you cant plaster over it or loose joint tape, your best bet is to remove it. If it’s Artex underneath you can successfully skim it but it needs the right prep. get a spread in to look at it, he will soon tell you.

3) Should overboarding & skim be considered? 3 pieces of 1800*900 will cover it.

Possibly but get someone to look at it & see if the situation can be saved. If you do overboard your better off using full size 2.4m x 1.2m boards, less joints less chance of cracking; use 12.5mm board not 9.5mm.

On the 3rd point, I think the new plasterboard can go snug to the existing without battens. Correct? (Battens at 450 intervals are already in place between rafters and existing board. Obviously screws need to reach into the rafters to take the weight.)

Yes fix straight over the top, no battens; don’t really understand where the battens are, is it packers between the plasterboard & the joists? Make sure the existing PB is well secured to the joists using additional screws. Screws for the new PB must go through into the joists, maximum spacing 230mm, stagger board joints long edge across the joists.

 

[acmedone]

On the 3rd point, I think the new plasterboard can go snug to the existing without battens. Correct? (Battens at 450 intervals are already in place between rafters and existing board. Obviously screws need to reach into the rafters to take the weight.)

Yes fix straight over the top, no battens; don’t really understand where the battens are, is it packers between the plasterboard & the joists? Make sure the existing PB is well secured to the joists using additional screws. Screws for the new PB must go through into the joists, maximum spacing 230mm, stagger board joints long edge across the joists.

The existing battens are 2x1 running perpendicular to the joists ie, there is a gap between joist & existing ceiling.

 

[Richard C]

The existing battens are 2x1 running perpendicular to the joists ie, there is a gap between joist & existing ceiling.

Why are the battens there, what purpose do the serve? Might be a weight issue if you overboard & only fix to the battens; is the 2” dimension the width?

 

[acmedone]

The existing battens are 2x1 running perpendicular to the joists ie, there is a gap between joist & existing ceiling.

Why are the battens there, what purpose do the serve? Might be a weight issue if you overboard & only fix to the battens; is the 2” dimension the width?

Yes they are 2 inches wide and are spacers, not weight bearing. I don't know the original reasoning but my thought is that it allows the pb edges to be joined accurately without having to meet at the joists. In other words, new board would similarly be mechanically attached to the joists but the edges tweaked into alignment by screws into the battens.

 

[Richard C]

I’m not really sure why the battens are there; ceiling boards should be close butted long edge across the joists with the short edges staggered & meeting in the centre of a joist; providing the joist pitch is no greater than 450mm 12.5mm board when plastered needs no additional support with noggins or battens. I’m still not clear what you have as you say there a 1” gap between the joists & the ceiling (boards) but the boards are fixed into the joists! So are they just hanging there on the screws or are the fixings only located where the battens cross the joists? Fixings should be into each joist, around every 200mm & no greater than 230mm.

 

[acmedone]

I’m not really sure why the battens are there...

The house was built in the 70's. They did weird things then.

 

[AlanHamill]

Before goig through the needed steps for prepping and painting , you need to address the concern of why is the bathroom holding this much moisture. Why is it not being drawn out. From what you are describing I must wonder whether you have an exhaust fan system in the room. If you don't, I would highly recommend one be installed. (Don't buy the cheapest on either.) If you do have one then we must find out if it is actually removing the moist air or just running. I have repaired several which were installed but were never hooked up to ductwork running to the outside envirionment. Instead they were buried in the insulation and of course not removing anything , just running. One thing most people don't think of is where is the replacmeent air coming from when the fan is running. If the bathroom door is closed the only air to come in is from under the door . Not much volume. Leave the door open after showering with the fan on a good half hour or more. Takes a while to remove the large build up of very moist air.
Zinnzer Paints makes an excellent mildew proof paint called Perma White and it's tintable. (that's right ! Mildew Proof!) I have a bath that has no ventilation in it and use to have the same problem, Mold and spotting, constant washing of the ceiling etc. It has been five years since I used the Perma White and I haven't had that first problem pop up! Also, I used the Satin finish and it still looks great.