Metal roof trusses ?

[ChippyJoe]

Does anyone know any manufacturers of (lightweight) metal roof trusses - I know that wide span, low angle ones are used in a lot of sectional buildings and wide garages. I'm widening my garage and cannot have too high an apex and will be using sheet metal panels.
Many thanks

 

[ChippyJoe]

Muddling my words above, I think correctly called a 'low pitched roof' to be on my garage !

 

[noseall]

I wouldn't have thought a metal truss would be much lighter than a standard timber fink truss.

However, if you are fitting metal sheets, you need a purlin-z bar arrangement surely?

 

[chickenlips]

What span and height would you be looking at ?

 

[ChippyJoe]

Many thanks for replies, very encouraging to feel I'm not alone trying to work it out - your remarks have already helped me understand my requirement better but to explain more, in fact I have both a garage requirement and also a 'lean to the side of the house to a wall' bit of roofing requirement.
In the case of the garage the span will be 5m, with the apex about 0.6m above the side walls which would mean a 13deg pitch either side, and in the case of the 'lean to' will be a span of 5.6m with the right hand side being 0.6m higher than the wall on the left, meaning a pitch of only 6deg.
I wanted to use steel roof cladding, for example the plastic coated type such as:
[http://www.steelroofsheets.co.uk/products.php?cat=6] or similar.
Does this sound a reasonable roof plan and what sort of truss/purlin should I use - I had thought a lightweight metal system may be required but maybe a wood truss could be OK here ? Hope my questions make some sort of sense.
Thanks, Joe