damp patch over chimney

dave09

I have a damp patch over the chimney on the ceiling. I live in a bungalow, the attic floor where the damp patch is bone dry, there's no pipes where the patch is. had two roofers out, don't seem to know what it is. Recently had the flashing done, any suggestions as it is getting worse.

japbyrne

this sounds like you had no problem before the flashing was done, if so there is a leak at the flashing. if you replaced the flashing because you had a leak chances are you still have a problem in that area. check your gutters around that area make sure their clear.

ircoha

Dont know what you mean by 'just got the flashing done', however there is a problem with the flashing at the chimney, I had the same problem from driving rain getting up under the concrete roof tiles and in behind the poorly fitted roofing membrane, as a temp measure I have put a little expanded foam along the offending concrete roof tiles and am awaiting some rain:)

gsxr1

could the roofers have spilled some patination oil . this would stain and appear dry .

January had some hard driving rain and I have repaired a clients flashing . High winds can lift and even bend flashing.

Also. do a quick check of your ridge tiles. Water could be rolling down the felt from the ridge and dripping down your chimney stack.

dave09

i had the problem before i got the flashing done the roofer changed the felt and checked the whole roof even he doesnt know whats causing it he did not charge me because the patch is stil there its always very wet in the mornings then drys out when i put on the heat in the house

Avns1s

I had something similar to the OP's problem. Roofers checked flashing, slates, felt, etc. All was ok.

Turned out that the white songe finished plaster on a tall chimney was absorbing enough water during heavy rain and allowing this to find its way down the blocks and come out on the Ceiling and the side of the chimney.

The fix was to apply Thompsons water seal to the chimney. 2 coats and it's been perfect since.

OP Check that there's no crack on the sides or top of your chimney and if it's not been recently painted (top included!) perhaps painting or the water seal stuff might help your problem.

sinnerboy

how old is the building?
is the stack brick or rendered?
is the attic converted? if so when ?

dave09

its a detached bunglow 22 years old the damp patch started at the side of the chimney then made its way up to the ceiling the attic is not converted i know it has to be coming from somewhere but were i dont know

dave09

dave09 wrote: »

its a detached bunglow 22 years old the damp patch started at the side of the chimney then made its way up to the ceiling the attic is not converted i know it has to be coming from somewhere but were i dont know

lads tried all your suggestions problem still there any more suggestions would be very helpfull I attached a photograph of it can anyone help

2 stroke

Is your fireplace unused/blocked up/unventilated.

Could it be something silly like the flue liner pipes being inserted upside-down, any water going down the chimney being directed out at the joints instead of being directed down.

gsxr1

dave this may sound a little off topic but have you ruled out a leak in your tank or pipes up stairs. Water can travel along the bottom of the joist inbetween the plaster board and settle on a low spot in a completly different place.

It is worth a cheak. I have seen this happen before with a puddle forming on the other side of the house from where the leak was...

Had that heppen to me in my previous house, my neighbour had a downstairs vanity unit and there was a damp patch my side of the wall directly behind it.
The pipe that leaked was in the attic and the water was running down the outside of the pipe.

dave09

the fireplace was blocked up for a year unblocked it about 3 months ago thinking it would make a difference ithink i will have to get a camera down the chimney to see what that shows up and then go from there

muffler

As others have pointed out it could be a number of things and frankly its a process of elimination if the problem isnt obvious.

As the roofing and flashing have been checked its down to the chimney flue or a pipe.

I recall a valley being stripped 3 times before the fault was found - hairline crack in the lead flashing.

slavetothegrind

ircoha wrote: »

Dont know what you mean by 'just got the flashing done', however there is a problem with the flashing at the chimney, I had the same problem from driving rain getting up under the concrete roof tiles and in behind the poorly fitted roofing membrane, as a temp measure I have put a little expanded foam along the offending concrete roof tiles and am awaiting some rain:)

Was working in an older house recently and the owner decided on a similar route with foam, he got the whole underside of the roof sprayfoamed, timbers and everything! Attic now a sweatbox to work in and he covered half my pipes in poxy foam!!!!!!!

Back on topic though a crack in the render of the chimney outside or the top will wick in moisture, has happened to a mate.
Also if you blocked up the fireplace you should have fitted a vent at the bottom.
Some good suggestions have gone before. Hopefully you'll find it soon.

dave09

lads i dont know much about chimneys anyone know of anybody who checks that sort of stuff and how much would it cost me

blindman

Is it actualy damp to touch or is it just a stain that keeps reappearing after painting. It looks like a stain that was carried from inside the unvented chimney. You will need to use a stain block like Bin primer before painting.
Fit something over chimney to keep rain out aspecially if you don't light the fire, allow some ventilation. If you fitted a oil or gas stove other side of wall did you have the chimney lined properly, if not this could be another cause of the staining. (I block mine completely in very windy and/or very cold weather and have been trouble free for 2 years even though there is a large crack in the chimney cap)

dave09

blindman wrote: »

Is it actualy damp to touch or is it just a stain that keeps reappearing after painting. It looks like a stain that was carried from inside the unvented chimney. You will need to use a stain block like Bin primer before painting.
Fit something over chimney to keep rain out aspecially if you don't light the fire, allow some ventilation. If you fitted a oil or gas stove other side of wall did you have the chimney lined properly, if not this could be another cause of the staining. (I block mine completely in very windy and/or very cold weather and have been trouble free for 2 years even though there is a large crack in the chimney cap)

its all about elimination, it is damp to touch every morning especially on frosty mornings it then drys out i haven't painted it since it started. i'll cover chimney and see how i get on thanks

muffler

It is most likely the stack but have you checked that you are not getting condensation dripping off the felt above it?

dave09

muffler wrote: »

It is most likely the stack but have you checked that you are not getting condensation dripping off the felt above it?

ye i put paper on the attic floor for about a week an it was bone dry this all started at the side wall painted red in the picture and made its way up starting to lose me patience with it

sinnerboy

dave09 wrote: »

the fireplace was blocked up for a year unblocked it about 3 months ago thinking it would make a difference ithink i will have to get a camera down the chimney to see what that shows up and then go from there

perhaps the blocking and / or un blocking has fractured your flue liner(s )

maybe a birds nest / wasps nest - in the liner / pot ?

can you post an 1. external shot and 2. a shot from within the attic

house is 22 years old - how long are you living there / when did problem start

( Sorry , more q's than a's )

roofer

it could be that the chimney tray is in backwards throwing the water back into the roof. i have seen this a few times

brickie No 1

hi all, i would say theres no lead tray build into the chimmey as the house was built 22years ago, the plaster on the out side off chimmey is failing if its block built you could try takin it off an replaster it or take it down to underside of roof putting in lead tray an rebuild an replaster same applys if brick built.