Guttering

[EARL]

I purchased a house recently that had a new extension the guttering that is fitted appears inadequate as any moderate amount of rainfall over flows the new guttering. I have checked the down pipe and it is clear. Is there any formula for the size of guttering and number of down pipes in relation to the roof size.

 

[TexMex]

Have you checked the level of the guttering. If it runs downhill the wrong way, it will do this. You could try putting it back up with a slight fall, in the right direction.

The easiest way to check this is to temporarily block the standpipe (a tennis ball may do the trick) and fill it up with water.

 

[EARL]

Thanks for the reply.
But the fall is ok i think the size of roof is the problem in relation to the down pipe and guttering size. The guttering takes the water from two roofs the extension has a run of just over 5 meters and the original roof running at 90 degrees too it is a 3 meter run. The down pipe is situated at the point the tweo meet.

 

[IanDB]

If you're feeling mathematically inclined you can plug some figures into this http://www.brettmartin.com/building/rainwater/designinfo/index.aspx and see what you come up with. I used to have a better link but appear to have lost it in the cyber-ether bin.

If your downpipe is in the centre of the gutter run, the flow along the gutter is halved so it could be just down to the design.

 

[DAZB]

This is a previous post relating to your question
//www.diynot.com/forums/viewtopic.php?p=28974&highlight=#28974

 

[price it right!]

hmm use high capacity guttering
not only will it solve ur problems it will cost too, well u have a lot of water dont you; afterall.