New Roof - lots of leaks - please help

[andymarshal]

Hi please help i just had an extension built on the back of my house which is a single storey kitchen extension with a 16 degree pitch and 2 velux windows in. the builder used edgmere slates from marley roofing and said that the sid elap of the tiles is allowing water to come in and sit on the felt. anyway his idea is to fix plywood to the roof truses, double felt it then add the battons then tile on top so basically water will be on the felt under the tiles. hE SAID THE BUILDING INSPECTOR GAVE HIM THIS IDEA.

I would like to know what you think about this idea. I looked at the marley site and the melbourne slates can handle this low pitch however there minimum pitch is 15 degrees - is this too close for comfort.

I would really be grateful for some advice.

Thanks Guys

Andy

 

[Static]

So basically hes done a flat roof construction with tiles on top?? Is the felt well lapped and bonded down? Did you agree to this variation from the original plans?

 

[Roofer]

When tile manufacturers test their tiles they have safety margins when stating the minimum pitch. If they say 15 degrees they are guaranteeing that they won't let in water, similarly Velux state the minimum pitch for their product is 15 degrees.

If you have leaks then something has been installed wrongly, you need to find the cause rather than rely on underlay to keep out water.

 

[andymarshal]

thanks guys we replaced the tiles with ones that go down to 12.5 degrees so there is no need for the felt however he velux is still letting in water although i think this may be the wrong flashing kit for this new tile.

thanks for the help

andy

 

[chappers]

As roofer says something is fitted wrong . Get him to take it off and start again Are you sure he doesn't come to work on a horse. Your original tiles and your velux are fine for that roof.