We recently bought a house that had an extension built around 2015. The extension was approved by whatever agency approves things. The extension is brick and lightweight block with plasterboard on the interior walls.
We detect an odour of earth or mould in the extension. Also, the wife gets symptoms of mould exposure. When the heat is turned up, we can't smell the odour.
There are no signs of damp visible on the interior walls or ceiling. There are no visible holes in the exterior mortar and the brickwork looks sound. There is a fsmp course.
We checked the loft above the extension and cannot detect the odour and there are no signs of water intrusion. I couldn't get all the way over the extension to pull some insulation.
There was a small porch (about the dize of a phone booth...) added some time after the extension. There was a water leak which we had repaired. There is no mould odour in the porch.
Thinking it could be in the wall cavity, we pulled the electrical outlets and sniffed, no odour.
We cannot detect a similar odour outside. The rain gutters are clear.
Our next idea is to drill some holes in the wall to access the cavity. We'll use an inspection camera and use a flexible bellows a and hose to try to detect odour.
Before we start drilling holes, does anyone have any ideas?
