Mould on new plaster - what should we do?

[tokyotecubate]

Hello all!

 

Happy New Year - Wishing you all a great year ahead with trouble-free builds.

 

We have been undergoing a full house renovation over the the year, where our builder has plastered our walls at around early December. 

 

We have been away for around 2 weeks in December to visit family, and when we came back to see the house and the work that was conducted, we were shocked to find the new plastered walls in our utility space ridden with mould ( see attached)

 

The wall behind the plasterboard is the original brick wall, where the plasterboard is being dot and dabbed onto the existing wall. 

 

I wonder what could have caused the mould, especially since it is a freshly plastered wall? Is it because the plaster was not dried well ( the builders might not have applied enough heat and ventilation to dry the plaster), or is it because of some inherent problem, like rising damp? Would it be a leak? ( there should not be any pipes behind but on top of this wall is where the new extension meets the existing wall - see attached joint detail of the flashing above that wall)

 

I've read that the plasterers should apply the primer onto an existing brick wall before applying the dot and dab to prevent existing damp to transfer to the plasterboard - does this seem the plasterers might have skipped this step? 

 

Would be very grateful if you could advise us what to do about this wall - would we need to remove the plasterboard and re-plasterboard + skim the area, and what should we do to prevent this from happening again? 

 

Speaking of - to pile on top of this problem, our builder has gone AWOL since christmas. We have observed them putting much less men ( and many times, no guys) at all on site, despite them having missed not one, but 2 extended deadlines for move in ( we were supposed to be in end of August, with the deadline being shifted to end of November, and now they cannot even meet a new extended deadline of end of December for only key tasks, such as painting and tiling). When we asked them about the much less progress and men on site since end of November, the builder claims that he will be working over christmas, and that the key jobs will be finished. When we came back to the house after christmas, the house was in such an incomplete state that it was far from anywhere close to completion. 

 

In other words, we cannot rely on our builder and will have to find other trades to finish up this job, and to fix this mouldy plastered wall. 

 

What should we put out as a job to fix this, and approximately how much should I budget to fix up this bit of wall? 

 

Thank you so much, and looking forward to hearing your experiences ( both in dealing with mouldy walls, and to deal with rouge builders)

[nod]

It’s just dry out in a cold house 

Bang a little bit of heat on Let it dry 

Brush the walls Then lightly  spray with 5-1 mix of bleach and water and wipe with a sponge 
 PAINT 

[Conor]

Open some windows if not using dehumidifiers.

[tokyotecubate]

@nod and @Conor - that is great news! So basically letting it dry out, wash the mould out with bleach, and then it's good to paint? 

On another note - any advice on how to deal with builders who drags and delays your job? better to find other trades and move on?

 

Edited January 1 by tokyotecubate

[Jilly]

If you are not happy, it’s acceptable to have the conversation, agree the financials and move on. Be prepared to compromise.
 

 It can be tricky booking good trades at short notice, mind you, so try to get recommendations from friends asap.  If you can move in and rough it you’ll save rent, but trades hate working round folk.