The house we have moved into has two chimney stacks with a fireplace on each floor( making 4 fireplaces). Downstairs fireplaces contains an old gas fire and the other is just boarded half full of soot and look relatively damp free. Upstairs one chimney breast has brownish tar like stain at coving working down following the pipe to the blocked fireplace containing a vent. Is this likely to be staining? The other 1st floor chimney breast is blocked with no vent. It has damp (clear not stained) at the top . In the loft above the stack looks dry. Should I install a vent ?

Hi there,

Hard to say without seeing, but you should definitely maintain some ventilation in the chimney.

Obviously check for leaks at flashing etc. and make sure that the cowel is doing its job.

Sometimes problems develop with hydgroscopic salts (origionating from the soot in the chimney) contaminating the plaster and drawing moisture out of the air. If this is the case you'd have to hack off the plaster and waterproof the chimney before making good.

Hope that's of some assistance. Give us some pics if you need further help.

All the best,

Ben

Thanks. I have attached some pics. I started to remove the wallpaper from the chimney. Well it fell off! Did it with a mask, and bagged it up as didn't like the look of that black stuff.