Plasterboard type for bathroom ceiling?

[les_danger]

Hi all,

Sorry if this isn't the right place! I've got an old lath and plaster ceiling in a soon-to-be bathroom that needs to come down. I was planning on just boarding it with moisture resistant plasterboard and getting it skimmed. However google led me to this thread from years ago: https://www.diynot.com/diy/threads/plasterboard-ceiling-in-bathroom.74691/ which mentioned duplex board, and also considered the insulation in the space above. For me the space above is a very very uninsulated loft space. Not sure if that makes any difference?

 

[noseall]

Hi all,

Sorry if this isn't the right place! I've got an old lath and plaster ceiling in a soon-to-be bathroom that needs to come down. I was planning on just boarding it with moisture resistant plasterboard and getting it skimmed. However google led me to this thread from years ago: https://www.diynot.com/diy/threads/plasterboard-ceiling-in-bathroom.74691/ which mentioned duplex board, and also considered the insulation in the space above. For me the space above is a very very uninsulated loft space. Not sure if that makes any difference?

A VCL in this location may make a modest difference, but you'd have to consider lifestyle and the rest of the upstairs ceilings. It wouldn't hurt to use Duplex.

 

[endecotp]

the space above is a very very uninsulated loft space.

While you're in Wickes buying the plasterboard, get a few rolls of loft insulation and fix that problem as well!

 

[^woody^]

Moisture resistant plasterboard is a waste of time in this situation. You're better off fitting foil backed plasterboard as a means of controlling vapour entering the cold roof void. Adding quilt insulation above will prevent condensation and pattern staining to the finished ceiling.

 

[Murdochcat]

Lots of Insulation AND a decent extractor fan?

 

[robinbanks]

For me the space above is a very very uninsulated loft space. Not sure if that makes any difference?

makes a huge difference; your warm moist air in the bathroom will condense easily on the freezing cold plasterboard, soaking it damp (it'll never dry properly) and making it a breeding ground for black mould

Even if you painted the ceiling with impervious latex paint, it would be slick with condensation for protracted periods and go mouldy

Insulation is more important than plasterboard type here; if all your local build shop had were standard PB and rolls of wool, you'd buy that rather than drive to the next town over to get some more specialist moisture/foiled PB and skip insulation

Mould control means keeping moisture evaporated in the air until it can be purged from the building, and that means keeping it away from cold surfaces