Overhanging Roofing felt.

[stevejw99]

I'd be very grateful if someone here is able to give me impartial advice.
I have a problem with my roof/guttering at the moment, when the rain is very heavy I have a few damp spots on the walls and water comes in, via the cavity, and in through a window frame.
Anyway, I've had a few tradesmen in for a quote, one of them said that

....the roofing felt should overhang behind the gutter, so that if the gutter overflows in heavy rain it runs off the felt harmlessly and not into the house....

This sounds a bit strange to me, as I can't imagine roofing felt to last very long when exposed to the weather like this.
His solution was to take back 3 rows of slates and replace the felt under these.

Thanks in advance.

 

[noseall]

when fitting the sarking membrane (felt) you should allow the felt to protrude past the fascia by about 65mm. this felt drip will then be let into the gutter when fitted.

eventually this does rot away, usually at the point where the tiles rest on the fascia.

to overcome this problem, we first lay a 'drip' of 12" dpc, over the rafters prior to fitting the felt. again, this drip will protrude past the fascia by 65mm. this secondary layer will keep on performing long after the sarking felt has perished.

 

[stevejw99]

Thanks Noseall.
When the roof was last done no one put any DPC drip in place. I think I'll get a few more roofers in and see if any of them come up with the same requirements.

cheers