Author Topic: V-shaped corrugated plastic?  (Read 332 times)

V-shaped corrugated plastic?
« on: October 30, 2020, 01:22:53 pm »
I'm buying A house with a decent side passage about 1m wide. I'd like to cover this over, but not have the rain spill into next door's garden. Is there a solution, such as v-shaped, corrugated, transparent plastic, that'll allow me to do the job? I can then funnel the water into my own fresh water drain. Any other ways?
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Re: V-shaped corrugated plastic?
« Reply #1 on: October 30, 2020, 02:30:15 pm » - lots of stuff there* - you would need to make a sloping timber frame of some sort and then fix guttering and downpipe to get the water to your drain.  Use 3 x 2 treated timber for the frame - you'd need to work out how the frame is held up.

You MAY be able to find some sloping metal brackets if it's only a metre span - just fix to the wall and attach guttering.

Tip: make sure you put the fixing screws through the top of the corrugations not the "valley" otherwise it will leak!

* the branch in Cov, on the ring road, usually has most materials in stock

Edit: On reflection you might be better with flat polycarbonate sheets rather than corrugated - and a simple triangular timber frame just attached to the wall - the sheet material weight almost nothing.   If it wasn't for this beastly Covid stuff I'd offer to give you a design and build quote as you're relatively local!

The other idea which looks nice is instead of a downpipe tube from the guttering to to have a length of chain (links about 4cm - plastic would work) just hanging down and water runs down it into the drain.
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Re: V-shaped corrugated plastic?
« Reply #3 on: November 12, 2020, 07:26:24 am »
You could slope it the other way. Not towards the house but to the back or front so water stays on your side. Or stop the canopy slightly short of the boundary.

Re: V-shaped corrugated plastic?
« Reply #4 on: November 12, 2020, 08:07:56 am »
where is the boundary exactly? If you are worried about tipping water into your neighbour's garden this suggests that the boundary might be within the envisaged span of the roof? If so this is not a good idea (even if your neighbours are amenable at present) because it will lead to problems should your neighbours sell up.

  In theory you should at least confine the span of the roof and  the water from it to your property and the usual way that is achieved (with a single-pitch carport or whatever) is to have a gutter set to collect the water off the edge of the lean-to roof.  If this is set correctly within an open  structure you ought to then be able to clean it from your side without difficulty.  The roof needs to be set high enough that the gutter can then have a cross-piece or cross-pipe to take the water towards your wall and thence into your drain.

If you try and make the roof with a double pitch and a valley or a single pitch facing towards the building the valley/gutter will be difficult to clean and troublesome when it clogs up.

Regarding strength of the structure, the roof ought to be strong enough to withstand snow loading (wet snow can be much heavier than you might expect) and wind loading.  Wind loading can again be much greater than you might expect, especially in a gap between buildings; a 1m wide lean-to  can easily develop as much 'lift' as an aircraft wing when the wind catches it right.


Re: V-shaped corrugated plastic?
« Reply #5 on: November 12, 2020, 10:59:46 am »
There's a company local to me that's been my goto for any plastic roofing for years - they have a selection of widths for your purpose, and all manner of other sheets and bits