On Wednesday, 17 May 2006 07:41:23 UTC+1, Thomas Prufer wrote:
On Tue, 16 May 2006 20:26:06 GMT, raden wrote:

Yeah, but they have proper winters in Bavaria, unlike here

Onduline is still crap!

Mine's seven years old, and I can get maybe three more years out of it. It's
been repainted once with bituminous glop: The red color came off after a few
years, and after pressure-washing the algae and moss off (under trees, north
side) the glop looked a good idea. (Glop doesn't last long, though.)

It's on a well-built roof: solid t&g cladding, a layer of bituminous summat
tacked onto that, another melted over it, and the Onduline nailed on that with
special nails with litte plastic heads. It'll be waterproof even if the Onduline
were leaking.

A roof with just Onduline and no layer of something solid under it would be a
sagging nightmare! Once it sags enough for water to pond, freeze, collect
leaves, you'll step out onto it to patch it, fall through, and curse the stuff.
'Pends on pitch, of course.

Still, it's very cheap, easy to use, a breeze to install alone, and quiet under
rain. (You *do* have rain, seeing you don't have winters?)

I'd look for something more durable: Wood cladding and bituminous shingles
hasn't been mentioned yet, I think.


Thomas Prufer

Yes, you're right about sagging.
It's largely caused by the interior of the building getting hot. (Black roofs don't help).
You can reduce the problem by making sure the building has lots of ventilation to keep things cooler.
Maybe some sort of light reflective finish would help too.
Aluminium paint????