Dampness - Following insulation

mlife

In an old house and got walls and attic insulated. House is small and is heated by radiators which works very well. Used a dehumidifier to remove moisture from the house. Since then two issues have occured:

1) In the two bedrooms moisture is occuring just above the skirting and on top of the flooring next to the skirting. A small bit of mould has appeared also.

2) The bathroom which is small and not well insulated due to it having a flat roof has the same type of issue but worse. In the eveing there is moisture on the toilet tank and moisture from it on the floor. The area has a radiator there that is heating the area but due to the roof it remains cold. This has lead to mould on ceiling.

Any advise on how to resolve the issues would be much appreciated.

BryanF

mlife wrote: »

In an old house and got walls and attic insulated. House is small and is heated by radiators which works very well. Used a dehumidifier to remove moisture from the house. Since then two issues have occured:

1) In the two bedrooms moisture is occuring just above the skirting and on top of the flooring next to the skirting. A small bit of mould has appeared also.

so you dryklined an old house. essentially hiding the mould/ condensation problem behind the drylining. this is now penetrated the plasterboard and is visible on your internal finishes. id start by taking down a small section and inspecting the structural wall behind. is there a wall vent?

2) The bathroom which is small and not well insualted due to it having a flat roof has the same type of issue but worse. In the eveing there is moisture on the toilet tank and moisture from it on the floor. The area has a radiator there that is heating the area but due to the roof it remains cold. This has lead to moul on ceiling.

same as comment above. but also is there an extractor fan in the bathroom?

mlife

Didn't dry line the walls but instead got beading put into the cavity blocks and foam into the attic. When the heat is on it doesn't take long to heat the place.

BryanF

mlife wrote: »

Didn't dry line the walls but instead got beading put into the cavity blocks and foam into the attic. When the heat is on it doesn't take long to heat the place.

ok please outline the location and number of wall vents & mech ventilation in bathroom?

then next id be questioning whether there are any cold bridges associated with poor detailing or workmanship at the base of cavity, made more pronounced by the insulation install. maybe consider weep holes drilled in the bottom of the cavity to the external would help, but this should be surveyed on site by arch/surveyor/damp specialist before deciding on a course of cation

MicktheMan

mlife wrote: »

Didn't dry line the walls but instead got beading put into the cavity blocks and foam into the attic. When the heat is on it doesn't take long to heat the place.

Cavity blocks (aka hollow blocks) or cavity walls (2 distinct walls with cavity between)?

mlife

cavity blocks.

BryanF

mlife wrote: »

cavity blocks.

that explains alot. sorry for your troubles. I'd be looking at the outside/external wall and painting the hell out of it as a remedial measure.

MicktheMan

mlife wrote: »

cavity blocks.

Did you have this issue (or any sign of it) before the insulation upgrade?