Fitting Onduline - specifically the verges.

[Rob Graham]

I've used these bitumenous corrugated sheets on a number of occasions but this time it is the pitched roof of the garage.

Because the roof is pitched and has barge boards, I opted this time to go with the specific verges rather than just rolling the sheet over the edge and nailing it down. The roof currently is properly felted - getting old, but not leaking - on sarking, and as done previously, I am just leaving the felt in place.

I have two problems - one is that the 200mm x 200mm wide verge (by 1m long) overhangs the barge board by about 60mm - does anyone know if this a 'problem'?

The second is giving me grief as the supplier's website (Ariel) does not address fitting these verges such that it is not clear if the verge goes on first such that the corrugated sheet is nailed on top of it, or is nailed on after the corrugated sheets are fixed such that it is holding down the first couple of corrugations.

It wouldn't surprise me if there is a YT video on this other than the short one from Ariel just doing a tiny garden shed, but I haven't found it.

Thanks for any help. Rob

[Tim Lamb]

In message [e-mail], Rob Graham [e-mail] writes

I don't know anything about Onduline but verges are always fitted on top of other corrugated roofing.

[Bev]

I did just that with one of the sheds a couple of years ago.

Can't see why?

Agreed and what I did.

[PeterC]

Looking at a pic of the verge on top, where does the water go? Looks as if it runs under the verge and down the barge board and building.

[Tim Lamb]

Most buildings are rectangular so the water can't get in at the top (should have a ridge cover).

Non square buildings need a bit more care!

[PeterC]

Sorry, I meant that the verge is on top of the corrugations, so water running down the valleys will go under the verge.

I'm looking for something to go under the Onduline as some water gets onto the deck. I couldn't extend the Onduline as there's a published limit to the overhang past the lst row of nails. The roof is single pitch and the higher end is exposed tp the rain and wind. I've tried all sorts of things but nothing holds by friction due to the flexibility of the sheet; I'm relutant to start banging more nails.