Build a lean to

[gtRTSdh]

I'm moving to a new house and to the side of the house is a head height walled in pathway from the back garden that doesn't lead to the front of the house. It's begging for a roof and door to keep garden tools in. I don't have measurements yet but I'm thinking it's a 1-1.2 wide and 3 metres long.

There's only tarmac parking over the other side of the wall.

There is a window alongside the pathway so I need to use a (very) clear roof to let the light through. I'd like to make it pretty much fully weather proof, and I was thinking of using corrugated plastic supported on wooden beams, would only need to be 2 by 1 as there's no weight to the plastic. I could use flashing such as this:

http://www.ebay.co.uk/itm/121130157859? ... 1436.l2649

In reality I don't know where to start and it's difficult to make the corrugated section weathertight, anyone got any ideas, experience?

 

[FMJ]

Your neighbour may not be impressed with water runoff on to their tarmac parking. Plan to put in some eaves for water dispersion.

 

[Chopper the ex Copper]

I used this on a similar project...

http://www.nick-gray.co.uk/Polycarbonat ... m_x_1220mm

Much nicer than corrugated stuff, and easier to work with.

 

[MikeD]

I used the corrugated stuff. You can get flashing pieces that are corrugated to sit on top of the sheets and flat to go up the wall. I just used self-adhesive flashband stuff over that and onto the brickwork. It's been there a few years and not leaked yet.

Part-built:


Weekend project by MikeDavis, on Flickr

Was finished off with facias and stuff.

 

[MikeD]

The plastic's pretty light, but worth overbuilding a bit in case it snows

 

[gtRTSdh]

MikeD, liking it very bright underneath, I guess mine will be 2/3rds of the width of yours. I've thought about the run off, can enough water fall on 4 ft of roof next to a house be significant enough to cause issues?

 

[Elysarian]

I used this on a similar project...

http://www.nick-gray.co.uk/Polycarbonat ... m_x_1220mm

Much nicer than corrugated stuff, and easier to work with.

I was thinking of exactly the same stuff as soon as I read the OP

I've seen it used mostly for the roofing on conservatories and it does look a lot easier to work with (and seal) than the corrugated stuff.

It's also (usually) better UV-stabilised so it'll stay clear for longer.

 

[highlandsflyer]

I second the polycarb suggestion, you can throw bricks at it all day and they just bounce off!

 

[We_are_Stevo]

As in everything else in life, you get what you pay for...

...I have used the corrugated sheet to roof the pergola over our small piece of decking (Wicks is the cheapest if you don't have a local hardware store that knocks it out at silly-cheap prices like the place in Norwich when I built my brothers') and it is perfectly ok so long as you build in sufficient support; and make sure you use the proper plastic roofing screw caps...

http://www.ebay.co.uk/itm/100-PACK-CORR ... 0615256636

...or the sheets will crack (drill holes in the sheet first with a new, sharp bit) and the first time a strong wind blows will be the last you see of your nice new roof!

The only downside to it is the crap that still manages to creep under the overlaps between the sheets and resists all efforts to clean it out! :roll:

If your Missus can live with that without constantly nagging you to clean it out then all well and good; if not I would recommend spending a bit more and using the box-section stuff that butts up edge to edge and sealing it with good quality clear silicon sealant.

As for the run off (you are not allowed to build/install anything that encroaches on a neighbouring property in any way) you just need to run some plastic guttering along the edge into a downpipe and into a waterbutt. You'll be amazed how quickly it fills up!

That way you will also keep your water bill down when watering the garden

If you are building on concrete/Tarmac hard standing I would use bolt-down Metposts to stand the outer supports in; and find somewhere that sells cheap 3x3 fence posts for the uprights as you'll save a small fortune and they're ready-treated.

Apart from that MikeD's photo above is the ideal 'blueprint...'

 

[MikeD]

I guess the tricky part with the OP's plan is that he (I think) wants to bridge between the house wall and a wall on the boundary, so water run-off isn't as straightforward as adding guttering to a facia. You'd have to have some sort of channel/gutter on your side of the wall. I think you could probably put shed/greenhouse guttering on top of the crossways roof beams up against the boundary wall, with lengthways ones to support the roofing sheets -- if the lengthways bits are tall enough then the roof will end up sufficiently above the gutter. Depends on the boundary wall being tall enough, and indeed it being your wall

Bear in mind that anything fully enclosed will count as part of your permitted development rights, so if you ever want an extension you've used up some of the size you could have had. Unless they've changed all the rules again, I can't be bothered to keep up