Lead Valley v Polyglass

[Trigger55]

Hi - my first post so please go easy...

I'm in the process of getting a new shared valley installation on a 30's semi.

The contractor has provided a quote for Polyglass to replace the existing lead valley.

My understanding is both will last a long time if fitted correctly - lead will last longer but is the more expensive option.

Is there anything else I should know?

Thanks!

 

[noseall]

I'm in the process of getting a new shared valley installation on a 30's semi.

The contractor has provided a quote for Polyglass to replace the existing lead valley.

Is there anything else I should know?

Thanks!

Make sure he's using a low profile dry valley.

 

[Trigger55]

Thanks - I'm not sure!

It's 3 layer felt system - 2mm membrane, 4mm torch on second layer and a 4mm mineral cap.