Some fibre-cement slates are nearing the end of their life at around 30 years. There's a good example about 200 yards from where we last met! I don't know about embodied energy-type calcs, but bear in mind that the life of a real slate could be at least 4-5 times as long as a fibre- (and quite possibly asbestos-) cement 'slate'.

cant comment on the eco aspect but we used real slate on our project. it was a toss up between welsh and spanish, we went for quality spanish in the end - SSQ's Domiz 1st. They come with a 75 year guarantee and welsh naitonal parks approval. Nice looking slates, pleased with them.

Any up to date recommendations?

Currently considering our roofing options - we want Nordic style roofing perhaps standing seam but open to suggestions be it black and to last

To add - Catnic Solastream is the solar-panel augmented version of Catnic Urban, which yes is just colour coated Tata steel, def not for a salty atmosphere, and AFAIK not for inland either, as a cheap alternative to solid-zinc standing seam, as it soon shows rust streaks. Why should it do that, when the same-material (colour coated steel) works fine as 'corrugated iron'? Must be because as standing-seam, the metal has to be 'worked' and crimped, while profiled metal sheeting is not. Even cut ends don't seem to rust, whether done with the approved nibbler/shear tool (which nicely compresses the painted edge) or with more damage and paint-melting with a cutting disc (the nibbler only works straight across the sheet - if cut diagonally or curved, has to be disc'd). I guess the working/crimping disrupts the paint into flakes, which then hold water (as a clean cut does not).

We avoided steel for our roof and went with aluminium. It seems to be OK but I suppose it's only been ten years. Zinc is supposed to be very good, but I have no experience.

Fostertom wrote:

''Aluminium also not good at the seaside!''

FT, I guess you were galvanised into action to say that.... (I'll get my coat)

It is the anodised surface finish that gives aluminium the corrosion resistance for use on boats etc

Aluminium boats (or underwater bits like outboard motors) often have zinc anodes to stop them corroding, and use specific alloys with a lot of magnesium chrome manganese and whatnot for corrosion resistance. Smaller items like masts and fittings are anodised after all shaping and welding has been done - don't think this works for roofs where seams are folded in situ.

Aluminium is a bit awkward to fasten as it is too soft to use for satisfactory screws, so has to be fastened with a different material like stainless steel and eventually they corroded each other. Got to keep it away from anything copper or brass.

But I have a few aluminium masts from about 1970 I think so with the right treatment it can last.