Hi,

Our building survey said that our flat bay roof is 'coated with a bituminous material and will need replacing in the near future.' The surface of it viewed from inside the window is cracked and outside the rainwater drips off it in an arc all around the edge of it, on to the bay window area below.

My question is, please, how do these roofs normally drain? They don't seem to have guttering. Is it normal for the rain to just run off and drip onto the ground? Im just asking as if I get it re-coated and it still drips off the perimeter of the roof I will know whether it is right or not. I just kind of think water should be directed somehow from roofs.

Tanks is anyone has any advice or knowledge about this

Ramsay

Dear Ramsey

I think there are two issues here, the roofing material and how to deal with the water run off.

1) Bitumen based roofing materials such as felt are prone to leaking and tend to only last 10-15 years due to the effect of extremes of weather causing the material to harden/soften and then crack/Blister. There are far better and more attractive options these days such as EPDM Rubber membrane that will cope with all weather and UV light conditions and have a life expectancy of 50+ years. The materials are relatively cheap and easy to install for a trained professional or competant DIYer. Check out www.rubber4roofs.co.uk. Apologies for the direct sales pitch but I think either the Self Adhesive EPDM or One-Piece systems would be ideal for your bay roof.

2) The second question is related to water run off. I think Building Regulations state that any roof under 2 m2 does not have to have gutters installed to collect water run off and deposit in a drain or soak away. Therefore depending on the size of your bay window you may not need guttering, however it may be worth extending the roof slightly to ensure that the water clears the facia boards and window cill to avoid irritating drip drip noise onto the window cill.

Hope this helps
All the Best
Tom

thanks Tom very much, good advice.