damp - air bricks or chimney problem?

suiko

I live in a 1930s terraced house. Walls are cavity except for a solid one on the ground floor (living room) where there's an outside passage under the house (called "ginnel" up north, I think). In the last couple of years I've started to get a damp problem in the living room. Obviously this outside wall doesn't get wet, as it's covered.

Do I need an air brick? Or might it be because I stuff a bag with newspaper up the chimney in winter when there's no fire, to prevent the heat escaping so fast?

Thanks :-)

mebsie

Hi Suiko,

I live in a similar aged property up North - (ginnel is correct, or snickett, depending on which side of the Pennines you're from!).

I had a small problem with damp when I first moved in on an internal wall in a room which had had the chimney sealed up - no ventilation. My first course of action was to drill a few holes in the board covering the fire place to allow an air flow through the chimney. This sorted my problem out.

I suggest opening the chimney up first and giving it a few weeks to see if it clears up. This is by far the easiest and cheapest thing to try first! If it isn't successful then there might be a breach in your damp course (if you have one) or possibly something else. But these can be expensive to investigate and repair, so try this first!

suiko

Thanks. Will try that now it's less cold.

David_Aldred

Hi suiko - where exactly is the damp in the living room? Is there mould growth ?Are the floors solid or suspended timber and is there cavity wall insulation ? Kindest regards David Aldred Independent damp and timber surveyor

suiko

Damp is fairly much all over that wall low down, but only in one corner at the top. It's not really damp to the touch - I only noticed because of the black mould.

No cavity insulation - this is a solid wall in the ginnel/snicket of a 30s brick terraced ex-council house. I'm not sure about the floor. I always assumed it was concrete, but carpets are nailed down.

Kiran

suiko wrote: »

Damp is fairly much all over that wall low down, but only in one corner at the top. It's not really damp to the touch - I only noticed because of the black mould.

No cavity insulation - this is a solid wall in the ginnel/snicket of a 30s brick terraced ex-council house. I'm not sure about the floor. I always assumed it was concrete, but carpets are nailed down.

Bang the floor, you'll be able to hear if its wooden suspended or if you near virtually nothing then its proobably concrete.

Did you have damp before you blocked up the chimney?

Edit: If the carpets are actually nailed down then I would assume that its a suspended wooden floor. Use the very scientific bang the floor test to be certain tho.

suiko

Will try that at home tonight - I'm pretty sure it's concrete though. Carpets are tightly fixed - sorry, I'm not sure if they're actually nailed - again, will have a look.

No - no damp till the last couple of years, which is pretty much since I've been blocking the chimney.

DVardysShadow

suiko wrote: »

Will try that at home tonight - I'm pretty sure it's concrete though. Carpets are tightly fixed - sorry, I'm not sure if they're actually nailed - again, will have a look.

No - no damp till the last couple of years, which is pretty much since I've been blocking the chimney.

When you block a chimney, you need to let it breathe. A trick I have seen used is a length of 40mm plastic waste pipe, with fibreglass wrapped around wedged up the chimney.

suiko

Floor is concrete. I'd be very surprised if the chimney was totally blocked - it's just a recycling plant bag stuffed up, so I'm sure there must be some air movement.

ormus

you can try the old glass test for damp.
place a sheet of glass on the floor, sat on a ring of putty, underneath. make sure its air tight.
leave for 24 hrs. or more.

if there is moisture on the top of the glass, its condensation.
if its underneath, its rising damp from the floor.