Streetfield Flat Roof Warranty

[Streetfield]

We are having 2 flat roofs installed on our self build each 5m x 3m. Not sure whether EDPM or GRP at this stage (doing my head in) but we require a min 10 year installation and product warranty (house build warranty provider insists)  that is also backed by a insurer (guess if installer goes bust). Also must be transferable should we sell house in future. No doubt installer should cover this but any advice would be appreciated. On of flat roofs will have raised decking as it is a balcony. Both are warm roof designs (not that this should make any difference). Thanks Nigel 

[Dave Jones]

id be more interested on the design of the warm roof, what VCL and where etc.

 

If its a parapet wall how the capping will be detailed.

 

EDPM every time over GRP for me.

[Canski]

19 minutes ago, Dave Jones said:

EDPM every time over GRP for me.

I'm interested to hear the reason for this. Only because I much prefer the look of GRP but what are the downsides ?

I have had similar quotes for EDPM and GRP and was going to go with GRP for the looks. 

[SteamyTea]

6 hours ago, Canski said:

but what are the downsides

Bad workmanship.

If the people doing it don't know what they are doing, it will not be very good.

That tends to be true of everything though.

I think EDPM can too easily give the impression that it is as easy to fit as a newly ironed bedsheet.  I would do the same checks on both trades.

[Streetfield]

Thanks all, we are going with EDPM given it is less weather sensitive to install (still needs to be dry) and I think we will get a better finish with the secret drainage and deep fascia (warm roof) design. Flex R EDPM 1.5mm system.

[Dave Jones]

what make of VCL are they using ?

[Streetfield]

Think Damplas does it matter what make?

[Streetfield]

Still not resolved the flat roof. Finding it difficult to get a contractor who can provide the insurance backed warranty for product and installation on EDPM. Looking at cold applied liquid systems now (Centaur, TOR, Protec) as these seem to be the only ones where the contractors (who also do commercial stuff) know what they are taking about in terms of insurance. £6k however for total of 35m2 of preprepared flat roof (all insulation, OSB boarding and levels done) seems steep.