I had an issue with that in my attic. Was due to poor/no ventilation and condensation forming on the underneath of felt. Nearly ruined my roof trusses.
Bought a do-er-upper 2 years ago. Doing it up in the evenings. Waiting to do proper job on roof when extension will be roofed. Lots of issues, most understood. Some beggar belief. I take my hat off to the original builder, he got away with it.
You should see some of the shit I’ve had to redo and I’m just a have-a-go hero.
@Massey what would be the best way to go about putting down a base for a stove/hearth.
I was thinking mixing a bit of mortar, throw down a base of a row or two of bricks on the flat then just sitting my hearth stone on top of that? Maybe face off the bricks to the front and side with some thin stone?
If the floor is already there then just put down a couple of courses (depending on the height you want)of nice old red brick around the outside and fill in the inside solid,the put your slate or stone or tile or whatever on top.Simples.Be careful with the height of your stove as you need to match up the angled flu liner