I've lived in my house (rented) for over 6 years. The top half of the house is rendered. It was quite cracked when I moved in and at each annual inspection my landlord has said he was going to repair it... something that finally happened about 6 weeks ago. It had got to the point that moss was growing in the larger cracks and it looked awful so was well overdue some attention. I'd been expecting the old, cracked render to be knocked off back to the brick before new render was applied. This wasn't the case. The builders just applied a coat of grey stuff (I believe this is called a scratch coat) directly on the old render with wire mesh sheets embedded in it. Then the following day they applied the new render.
Six weeks later and I'm noticing areas of mould around the house which have never appeared before in all the time I've lived here. All over the bathroom ceiling, around my daughters window frame and a bit on her wall, along the skirting boards in my living room and around my dining room window. I'm not doing anything differently in terms of heating the house, all windows have trickle vents open 24/7 and I window vac condensation off them every morning if needed and they are opened every morning for a couple of hours. Our bathroom window is open 24/7. I dry as much laundry as I can either outside on the line or in the tumble dryer which is in the garage. On the rare occasion I do dry washing indoors I run a dehumidifier. So I'm wondering if these new mould patches are something to do with the fact that the old, damaged render wasn't removed so all the damp that had got into the cracks over the years has now come through the brickwork and into the house? Anyone know if this is likely?