Hey chaps. Hope you are all safe!
I own a 1950's(ish) pre-fab concrete house, with a flat roof. Appears to be Jesperson block type
Flat roof, last replaced around 15 years ago. During October, a leak developed, with water coming through the joint in the concrete panel ceiling/roof. I went up and had a look, Nothing major, no pooling or lifting of the felt etc. Spotted some cracks where the roof falls into the central downpipe. Temp patched with primer and flashing, then called out my friendly roofer to clean it all up, 1m2 torchon applied.
Huge rain storm a week later - no leak. Nada. Nothing. waited a few weeks, replaced ceiling covering etc. No issues.
January....during a nice try spell.....THE LEAK RETURNS. a few drips per hour.
The leak has gone and come back many times, but does not appear to be an immediate leak. We had torrential rain for a week, and it didn't even drip once. Recently been having a spell of warm dry weather, and the leak is at its worse for the last month.
Now, I have to assume the actual roof covering is waterproof.
I'm not sure of the construction under the felt, but there is clearly going to be insulation/plyboard of some type.
Is it safe to assume that the roof is indeed watertight, and the leak i have is residual water from the insulation being sodden/plyboard being sodden/rotten? The fact it is worse when it is sunny would suggest that - With the black( the silver paint has worn off) roof warming up, the moisture in the insulation venting off, and with nowhere to go, its pushing the remaining water into the cracks?
Or is it my nextdoor neighbour who has a huge puddle on her roof? I think that there is a barrier, but haven't been able to get that checked.....
I own a 1950's(ish) pre-fab concrete house, with a flat roof. Appears to be Jesperson block type
Flat roof, last replaced around 15 years ago. During October, a leak developed, with water coming through the joint in the concrete panel ceiling/roof. I went up and had a look, Nothing major, no pooling or lifting of the felt etc. Spotted some cracks where the roof falls into the central downpipe. Temp patched with primer and flashing, then called out my friendly roofer to clean it all up, 1m2 torchon applied.
Huge rain storm a week later - no leak. Nada. Nothing. waited a few weeks, replaced ceiling covering etc. No issues.
January....during a nice try spell.....THE LEAK RETURNS. a few drips per hour.
The leak has gone and come back many times, but does not appear to be an immediate leak. We had torrential rain for a week, and it didn't even drip once. Recently been having a spell of warm dry weather, and the leak is at its worse for the last month.
Now, I have to assume the actual roof covering is waterproof.
I'm not sure of the construction under the felt, but there is clearly going to be insulation/plyboard of some type.
Is it safe to assume that the roof is indeed watertight, and the leak i have is residual water from the insulation being sodden/plyboard being sodden/rotten? The fact it is worse when it is sunny would suggest that - With the black( the silver paint has worn off) roof warming up, the moisture in the insulation venting off, and with nowhere to go, its pushing the remaining water into the cracks?
Or is it my nextdoor neighbour who has a huge puddle on her roof? I think that there is a barrier, but haven't been able to get that checked.....
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