Drying out wet plasterboard

[b14]

Long story but our house is being fully renovated. New everything basically, inc roof. It is heart-breakingly expensive, and a high-end build. Builders got their schedule a bit wrong and the final bits of the roof haven't been finished before the plasterboard went on, skimmed and mist coat. Now of course, it's been raining and some bits have got pretty damp, with some added mould growing for good measure.

Builder says they'll dry it out, we're saying take out the wet stuff and replace. We're in the final stages of the build and moving in at start of November so we just don't want to have them do a rush job on drying it, paint it etc then find it causes problems and has to be replaced after we move back in.

Am I being unreasonable and drying rain-soaked plaster, removing mould etc is legitimately not going to cause us an issue, or am I right that this should really be replaced? It's not massive areas, one corner of a room and spreading plus some other bits that are looking a bit damp. Feels to me like it should be done right and we shouldn't have it hanging over us that the plaster might need to get ripped down and replaced after we've moved back in, which would be v disruptive, dusty and potentially damaging to the finishes that we've spent £££ on.

[BigRickus]

Unless it’s very superficial it needs replacing.

https://www.british-gypsum.com/documents/technical...

[119]

Yep, i wouldn’t have it as I think it will warp as it dries out.

Insist it is replaced!

[sfella]

Who made the call to plasterboard and skim before watertight,builder or client? So long as you didn't push and highlight penalty clause or something that forces them to skim before watertight its on them, if you backed them into a corner it's more grey who's liable.

For finish I'd replace but it'll need wet board cut out and replaced and whole ceiling skimmed or it'll never be right

[John D.]

The mould will keep coming back forever. Get it replaced.

[b14]

Thanks all. V interesting to hear that it's unlikely to come good. The builders are driving the schedule and they decided to plaster and skim before the roof was done, so it's all on them. They've agreed to replace but of course the next fun will be how far they go in replacing.

Frustrating, our builders. The finish is superb but they just aren't very organised, which is illustrated perfectly by this debacle. In a rush to get things done, they might have got away with it for a week or so of dry weather but it's been weeks since they boarded and skimmed it and only tomorrow is the roof finally getting finished.

[119]

You’ll soon see if they have patched it as the new plaster will dry differently over the patches.

[miroku1]

Plasterboard once wet is finished as I understand it .
Having worked for insurance companies whilst their contractors removed hundreds of metres

[nute]

I run construction sites (as well as doing other things) for a living. Unless it was very localised or superficial I would want it replaced.

[Jeremy-75qq8]

I appreciate I am an outlier here.

I would wait a week and see how it dries out.

If you touch it when wet it will fall to bits.

It also depends how wet is wet.

If just reasonably damp then I would give it week ( without rain on top ) and see.

I have just finished a very large build and it is hassle all the way so I feel for you.

[OutInTheShed]

You'll have dry rot spreading from the manky cardboard on the hidden face of the plasterboard.

It's fooked.

[WyrleyD]

If it's got wet it's f**ed and it will never be right , ask me how I know!

[GasEngineer]

WyrleyD said:

If it's got wet it's f**ed and it will never be right , ask me how I know!

How do you know?

[WyrleyD]

Had a stack of new boards get wet after delivery driver left them stacked up against a wall below the eaves uncovered and it rained, heavily and we were off-site. The boards just fell apart along the edge when we came to try and use them, these were Knauf square edge boards.

[wildoliver]

Only adding what everyone else has said. We had a kitchen all boarded out and I had to hack it all off after a roof leak as it had got wet. In that case water had got behind the boards too and was never going to dry out.

[dhutch]

miroku1 said:

Plasterboard once wet is finished as I understand it.

This is my thoughts too, slightly damp for a day or two is ok, but dripping wet for long enough to form mould its going to be knackered.

[John D.]

It's not so much the integrity of the board, more that the mould will never go away IME. It will keep coming back through any paint (even stain block!).