Roof leak..

feartheclaw

Hi all
I have a leak in my roof just below the chimney. Old house +100 years old.
I've had roof patched up where we thought it was coming from but it persists. Had 3 roofers out to look at it recently and 2 of them said roof looks ok, problem might be the old chimney itself and to apply a waterproof seal to chimney. Any thoughts on this and if it sounds like a good idea can anyone recommend a good sealer for the chimney??
Thanks
ftc

Right2Write

Is there lead flashing around the base of the chimney - to shed any water onto the roof covering proper? Slates? Tiles? Thatch ?

feartheclaw

Right2Write wrote: »

Is there lead flashing around the base of the chimney - to shed any water onto the roof covering proper? Slates? Tiles? Thatch ?

Hi, the flashing seems ok. The roof is the old slate type but seems to be fine as well (with some patch ups) The question is could it be the chimney causing water ingress and is it worth trying to seal it?

Right2Write

How big is the chimney and is it rendered or just bare brick or stone? Masonry will certainly absorb a certain amount of driving rain but it'll either soak through and water would drip down the chimney or just evaporate back out. That's what I'd expect anyway. A chimney is normally a small enough area facing the rain, so I'd be suspicious of that advice and be looking elsewhere for the leak. Water can travel sideways in a roof, so keep an open mind. If there's an attic, get a look up there with a torch the next windy wet day and see what you can spot. I'd be thinking it's more likely the water is getting in through some defective roof covering or flashing, gully etc.

feartheclaw

Right2Write wrote: »

How big is the chimney and is it rendered or just bare brick or stone? Masonry will certainly absorb a certain amount of driving rain but it'll either soak through and water would drip down the chimney or just evaporate back out. That's what I'd expect anyway. A chimney is normally a small enough area facing the rain, so I'd be suspicious of that advice and be looking elsewhere for the leak. Water can travel sideways in a roof, so keep an open mind. If there's an attic, get a look up there with a torch the next windy wet day and see what you can spot. I'd be thinking it's more likely the water is getting in through some defective roof covering or flashing, gully etc.

The chimney is bare brick but not too big - regular terraced cottage chimney.
There is no attic in this part of the house as its converted to living space so would need to open up ceiling which I'd rather not do. Also there is only a chimney stack as far as I can make out - chimney below roof level has been removed / no chimney breast etc. As mentioned 2 different roofers said roof covering was ok while not perfect...
Thanks ..

Right2Write

Grand - driving rain has a habit of finding weaknesses. Between the wind and suction due to draft, water can find ways and means to get in. Slope of roof and overlap of slates are important, so look at that too. Traditional slopes for slate roofs are c. 30 degrees plus from what I see on older houses.

Tradesmen opinions are valuable but people could give you a bum steer if they don't fancy a job or reckon it's too much hassle etc