Re-sealing a flat concrete outhouse roof

ed110220

slipperyshoe wrote: »

That detail is absolutely fine; felt is not self terminating but under cladding there is no issue whatsoever (so long as cladding doesnt leak!). Saying that the cladding should really be taken off to install this detail, overlap should be minimum 50mm. If you dont do this the risk of fire is great; you are unlikely to actually have a fire but the roofer will be so paranoid about starting one that he will use insufficient heat when welding.

FYI lead free flashing or GRP termination bar are also acceptable details for bitumen felt.

Would'nt go down the fibreglass roof, as poster said it is a good solution for domestic properties, however it is very expensive, can be tricky to properly install and is messy. It also does not have a longer (certified) lifespan than felts. I work in commercial roofing and it is not a viable option on any roofs for say 100m2 and upwards.

Thanks for the advice. I do not think it is possible to remove the cladding except from the inside, certainly not replace it. The bolts are accessible from the inside if you remove the internal wall linings as I have in places to insulate, but that's obviously not something you want to do just to renew roofing felt.

I don't understand your comment about fire risk as there is nothing flammable apart from the bitumen (roof is concrete and the adjoining house is steel/concrete).

southcoastrgi

ed110220 wrote: »

I don't understand your comment about fire risk as there is nothing flammable apart from the bitumen (roof is concrete and the adjoining house is steel/concrete).

yes agree slightly overkill me thinks

slipperyshoe

Fair enough on the fire risk; I'm used to working on larger commercial buildings etc so you cant be too careful. Check there is no builders paper, birds nest or wasps nests up there though. You'll do well to set fire to the bitumen by the way!

studio500

Hi Ed, i've used firestone EPDM on several flat roofs. It's very easy to fit on a diy level, cheaper than having a new felt roof fitted and can be overlaid over existing felt or just remove the old felt and stick down the new.
There are two types of adhesive one is water based and the other solvent based and very sticky. There are several suppliers and some even have instructional videos.

It can be tricky creating the lip under the cladding to the side of the house as when you remove the lower cladding you still have to deal with the ridges in the steel profile but I used the solvent based adhesive here along with flashing strips to make a good seal.

Heres a link to one company but search around on Google as prices do vary.

Marc

http://www.roofingwarehouse.co.uk/roofing/firestone-rubber-roofing.html?gclid=CJio_t3M2rICFaXJtAod7zMAAw

ed110220

Thanks Marc, it didn't occur to me before, but I've just thought that the roofing felt probably meets the house in the same position and way as on the more typical type of BISF outhouse?

randykurm

Roofing felt probably meets the house in the same position and the way of the more typical type of outhouse .