Strange wet patch along wall

~moneysavingnovice~

I've recently noticed a wet patch running along two walls of my bedroom, in a horizontal line, around 4foot above floor level.

The bedroom is an extension, and has 3 external walls, two of which have this strange dampness. There's no mould, and the volume of water is not huge (sort of looks like condensation).

I've looked at the outside of the walls, and can't see any rows of bricks which are wetter than others, no damaged pointing etc. I don't think it's rising damp, as the rest of the wall isn't wet. The walls aren't getting more wet either.

Could it be a burst central heating pipe? They could possibly be buried in the wall :S

Anyone got any ideas what it could be??

System

sounds like a cold spot on the wall, do you know the construction of the external wall?

~moneysavingnovice~

the_r_sole wrote: »

sounds like a cold spot on the wall, do you know the construction of the external wall?

Thanks for replying.

I bought the house a couple of months ago and the survey I had gives a couple of clues about the external walls of the extension:

-the walls of the back addition are only 9"
solid brick, which offers poor heat insulation and the chance of condensation

during cold weather (which I hope this dampness is, but it's strange that's it's in a horizontal line around 2 walls). Also:

-a new chemical injection damp course appears to have been put into the walls of the back addition (could there be a problem with this??)

Thanks again.

System

i wouldn't have thought a dpc would be as high as that up the wall, there should be evidence of what level the dpc is at on the outside, i think they drill brick for that...
it does seem strange that it's at one level right enough, if it's a solid wall there will likely be condensation at somepoint. not sure if the height might be where the dew point occurs, although i'm completely guessing that it would happen at a certain height!
will think on some more...

olias

Just a guess, but it could be that the mortar mix for that particular row of bricks was weaker than the others, therefore allowing damp in easier.

Personally with only single skin of brick, particularly in a bedroom, I would be looking at insulating internally, You could build a studwall against the outside walls, insulate inbetween, including a vapour barrier, then plasterboard on top. You will lose a few inches off the room size, but will have a warmer room and eliminate any damp or condensation issues.

Olias

System

olias wrote: »

Just a guess, but it could be that the mortar mix for that particular row of bricks was weaker than the others, therefore allowing damp in easier.

Personally with only single skin of brick, particularly in a bedroom, I would be looking at insulating internally, You could build a studwall against the outside walls, insulate inbetween, including a vapour barrier, then plasterboard on top. You will lose a few inches off the room size, but will have a warmer room and eliminate any damp or condensation issues.

Olias

good advice, i too would recommend lining the internal wall, but it would be best to find the source of the problem before covering it up, as if there is condensation on the wall after it is enclosed there will be no where for the vapour to go...

~moneysavingnovice~

Thanks again for all your helpful suggestions!

I hope it is condensation and not a burst pipe etc. Our surveyor also says in our report that he would recommend insulating internally like you two have said. The only problem with that is that it's a very small doublt bedroom as it is, so not sure we could stand to lose the extra space. Might have to though.

In the mean time, if it is condensation/water coming in from outside, would a dehumidifier help?

System

a dehumidifier would help with the water vapour in the air, but it wouldn't solve the problem!
technically you can also retrofit external insulation onto the wall, but it would be expensive, a lot of la houses had it done so the rooms weren't made smaller...
if you have a solid brick wall i don't think there would many pipes in an external wall...

~moneysavingnovice~

the_r_sole wrote: »

a dehumidifier would help with the water vapour in the air, but it wouldn't solve the problem!
technically you can also retrofit external insulation onto the wall, but it would be expensive, a lot of la houses had it done so the rooms weren't made smaller...
if you have a solid brick wall i don't think there would many pipes in an external wall...

Ha yeah, that's a good point!
Who's best to call to come and look at this then? A builder? Surveyor?

System

have you not got any friends or realatives that do anything like this?? seems a bit like non-moneysaving to call someone out!
if you think it might be something in the wall maybe a stud-finder tool would help you see if there is anything in that part of the wall, just before you call anyone out...
maybe take a few photos inside and out and post them on here, there's some folk much more knowledgable than myself on here that might spot something!