In order to get a downlight in the centre of our shower, it will need to be installed very close to a join in the plasterboard (handily shown by a hairline crack)
Will I get away with bracing the plasterboard across the join (from above/behind)? Or do I need to patch in solid section of plasterboard to span the join?
If it's a plasterboard join along that line doesn't that mean your proposed light position would be hitting a joist?
My approach in this situation would be to ask myself why I needed the light absolutely central to the bath.
If you get the angle right it'll illuminate your crack perfectly!
If the crack is where the join is, where does the ceiling joist run, does it span the crack by any chance?
Is there a joist nearby, spanning the joint?
As others have said, I'd assume there would be a joist. It's a bit unusual to have floating joints.
If you get the angle right it'll illuminate your crack perfectly!
Not the bath image anyone wants.
If the join is where the joist is (likely), then I'd go two downlights spaced evenly either side - maintain symmetry despite not being centred.
The joist is perpendicular to the crack line, so no joist behind the crack. Joists/trusses run front to back, the crack runs side to side of the house (hopefully only within the shower, not the whole house!).
Will the joist a) get in the way and b) support the joint adequately?
The ceiling joist is 160mm away so won't get in the way. I suppose the question I'm asking is will the joint be supported adequately
Is the cracking the result of how they are currently supported? Is there already another bit of plasterboard across the join at the back?
Is the cracking the result of how they are currently supported?
Could be. I don't yet know if anything is across the back already yet. If there isn't, even if I put the downlight elsewhere, putting support in will probably help the cracking
The join is already not supported properly as it’s cracked so drilling a hole next to it won’t make much difference.
I’d go with drill the hole for the light then cut two bits of timber as long as possible to fix along the length of the crack, fix through the plasterboard andrake the join out so you can get some filler in
If the downlights can cope with a double layer of plasterboard, then perhaps I can put a piece in above, over the joints and screw through from underneath. Then the downlight hole can be cut through both layers of plasterboard.