Im planning a flat roof extension with a central timber and glazed roof lantern on top.
the roof is circa 5 m x 6m
I should have enough height for a small parapet wall if necessary. at least on 2 sides away from my neighbour.
Im thinking of a green roof but am concerned about the material beneath being too short lasting and too prone to deteriation/leaks etc.
should I go for
or standard Bitumen felt
The roof may get some occasional foot traffic for maintenance. The roof lantern Im thinking of is vertical glazed upstand with pitched glazed roof. some of the panels may need to be obscured glass for privacy or indeed solid rather than glass.
The building is a Victorian cottage with lower than normal main ceiling and FF window sill heights. The location of the extension also dictates a flat roof next to our neighbours to allow light into their gdn. I am looking for a long term 100 year type solution so cost is not the overiding factor.
Ive heard of sarnfil membrane which may be appropriate.
Lead and zinc seem pointless as they will be covered with sedum and substrate.
Does any one have a view on green roof expected lifespan?
I am also intending to have 2 solar panels mounted on frames on it.
Any comments or help or experience appreciated.