We recently moved into a new to us (built in the 1940's) house.
One bedroom has a yellow stain on the chimney breast around the area where it joins the ceiling.
Work has been done before we moved in to re-tile around the chimney directly above where it passes through the roof and the lead work has been replaced.
The wall in the stained area does not feel wet.
However, i went and bought a cheap damp meter
http://www.bamr.co.za/downloads/Rapitest Damp Checker.pdf
Checking the stained area gave readings between 22-28%
Working away from the stain the readings got lower and eventually went to zero.
Which made me think that there must still be a leak from the roof above.
In the roof space where the chimney passes through the roof there was no sign of any water ingress that i could see. So with my damp meter i started checking the mortar joints in the chimney. 22-28% again.
I checked the surrounding woodwork, 22-28% again.
Odd, so i started checking random bits of wood in the loft area 22-28% again. I checked the mortar where the tiles are back buttered on to the laths (steeply pitched roof, no felt) which felt dry as a bone, again 22-28%.
So, i've come to the conclusion that my damp meter is a pile of cack, i'm not using it properly (which is unlikely because its not exactly rocket science to touch two prongs onto a surface) or my whole house is riddled with damp and its about to fall down.
On a serious note, can anyone tell me how i should actually determine whether this stained area is still damp or just and old stain or even a soot stain from the hydrocarbons that have seeped through the chimney.
One bedroom has a yellow stain on the chimney breast around the area where it joins the ceiling.
Work has been done before we moved in to re-tile around the chimney directly above where it passes through the roof and the lead work has been replaced.
The wall in the stained area does not feel wet.
However, i went and bought a cheap damp meter
http://www.bamr.co.za/downloads/Rapitest Damp Checker.pdf
Checking the stained area gave readings between 22-28%
Working away from the stain the readings got lower and eventually went to zero.
Which made me think that there must still be a leak from the roof above.
In the roof space where the chimney passes through the roof there was no sign of any water ingress that i could see. So with my damp meter i started checking the mortar joints in the chimney. 22-28% again.
I checked the surrounding woodwork, 22-28% again.
Odd, so i started checking random bits of wood in the loft area 22-28% again. I checked the mortar where the tiles are back buttered on to the laths (steeply pitched roof, no felt) which felt dry as a bone, again 22-28%.
So, i've come to the conclusion that my damp meter is a pile of cack, i'm not using it properly (which is unlikely because its not exactly rocket science to touch two prongs onto a surface) or my whole house is riddled with damp and its about to fall down.
On a serious note, can anyone tell me how i should actually determine whether this stained area is still damp or just and old stain or even a soot stain from the hydrocarbons that have seeped through the chimney.
