Plastic channel

Not cheap, but...

Bob, thanks for your speedy response. I hadn't thought of cable trunking: it's given me a new line to search for.

You're right about the price of that Pro-Power version from CPC, though it is for a 3 metre length and I would only need the one. Free delivery, too.

I wondered about cable trunking but I don't think it would have good UV performance.

Bill

Builders merchant. They sell plastic chaneel intended for roofing, the valley between intersecting pitched roofs.

Or guttering for commercial buildings - larger than the domestic type.

Difficult to obtain in small quantities - unless a supplier will send you a free 'sample' but larger than cable trunking is cable troughing, eg as used along the sides of railway lines. Available in concrete and concrete substitutes.

Or could you scrounge some 8" dia water / soil / gas pipe and slice it in half lengthwise?

Owain

Bill,

Yes, that did occur to me, too.

Harry,

Thanks for the link: I'll check it out.

PeterC,

Thanks.

Owain,

Thanks. Someone elsewhere suggested "trough" as a search term, which has opened up a lot of possibilities, including cattle feed containers and similar.

I did wonder about that, though scrounging enough (or indeed any, round here) would possibly be tricky.

Thanks to everyone for the thoughts and suggestions.

Or channel drain, without the grille if preferred

Owain

Owain,

That's a good one, and very reasonably priced compared to some possibilities. Thanks.

Thanks for those links, the first one especially. That industrial guttering is an ideal size, though it's a pity that the delivery charge is so high, presumably in part because it comes in four metre lengths.

Doesn't quite meet your size spec though. I think Wickes "high capacity" guttering might actually have a bigger flow area, and that comes in 4 metre lengths.

The sizes I gave weren't definite. And actually, the high capacity guttering is narrower (just) and less deep (considerably) than the drainage channel. Many thanks for the link though: all information is useful.