Mould on plasterboard - help!


New Member
Me again!

I’ve put plasterboard up throughout the lower level of the house and after a week of not being here I’ve come back to mould all over.

The house is a ‘building site’ with no heating.

Rewind a few weeks and the roof was taken off and redone due to extreme leakage, brickwork reprinted and tanking out on the walls to help with damp from the floor which had been a problem previously.

The upstairs has been boarded and plastered with no mould issues.

Downstairs boards - some have mould circles where I’ve dot and dabbed and others are pretty covered all over.
Do we think this is from moisture in the air or from the brickwork behind? And what’s the solution?
The walls that the mould is coming through the adhesive spots are internal walls the one that’s covered in the stuff is an external wall below a window.