Humidity in bottom wall

[lettywetty]

Hi,

I bought an old bungalow. I have 2 ground level bedrooms. I stripped the paper in the first room to replaster, room ok, there must have been a chimney in the corner as there is cement on the wall and old tiles on the floor in the corner.
In the second room just behind there is wall paper that I don't want to take away but I feel damp behind. It is in the corner of the room where there must have been also a chimney because I can see that the wall is irregular under the paper and there are also old tiles on the floor under the carpet. These 2 chimneys were next to each other, one wall is damp but not the other.
I went outside and saw at 80cm of the floor level, 2 old metallic brick vents next to each other, according to my measure one gives in one bedroom, the other in the other bedroom. These must have been put in place for the chimneys purpose.

Could the humidity in my wall come from one of these vents? Why one room would be humid and not the other one? Should we block them with cement to stop the humidity? There are no more chimney in the roof anyway.

Also the outside wall where are located the vents is hardly touched by rain as the neighbourg's house in only a meter away, so well protected.

Thanks to tell me what you think?

Letty

 

[lettywetty]

Sorry, not chimneys but stoves probably.

 

[KenGMac]

lettywetty, good evening.

In general terms, any Chimney Flue should be ventilated at the top [the pot] where a ventilated water proof cap should be fitted, it is also advised that the chimney flue be vented inside the property, generally a brick vent on the inner face of the wall in a position where air will flow up the entire height of the stack and stop Condensation occurring.

You note that one Flue is "Dry" the other is not? there is a possibility that a load of old material that at one time coated the internal surfaces of the Flue has fallen off and down to block the external vent, the air brick?

As a quick check, cheap and cheerful poke a length of flexible wire / plastic into the external air brick, if the probe is constricted on the "Wet" side Flue then there is a probability that the lower external air brick has been blocked off by material falling off the internal walls of the flue? just a test??

As an aside, any coal / wood / even Oil will produce Sulpfur when it is burned, the Sulphur will then adhere to the soot on the inner surfaces of the two flues, if rain water enters the top of the chimney [if not capped as noted above] will interact with the Sulphur to provide a very dilute form of Sulphuric Acid, this Acid then exacerbates the rate at which the internal lining of the flue.

Hope some of the above is of use??

Ken.

 

[lettywetty]

Thank you Ken, I'll try to poke.