cowboy job on a zinc roof?

[markh45]

Hi gents,

New to the forum having bought my first proper house.

The place we have bought had an extension done in june of last year with a zinc roof. This leaked in the storm we had about 3 weeks ago.

On inspection I saw that the seems on the zinc roof where it joined the original house were 'sealed' with what looks like silicone sealant. This is where it leaked. After about 2 weeks I managed to get the builders round to look at it and they put more silicone sealant on it and said this was the proper way fo doing it. I am not convinced!

below are some pictures to hopefully illustrate what has been done.

Please can someone tell me if this is right and if not what shoudl be done?

 

[hardmetalking]

This is a bit of a grey area.....
Some literature shows this kind of detail but we have always considered it to be weak and vulnerable. Common practise is to cut a chase into the abutment and fold the zinc into it and then back on itself. It's called a birds mouth fold as this is what it resembles. It is then possible to plug and screw through the birds mouth holding the flashing in place and then sealing the entire chase with lead sealant.
Done this way you wouldn't have the problems you are currently facing.