Polycarbonate overhang and guttering

[catlad]

I'd recommend laying at least 3 sheets before fixing the first one down as its hard to adjust once you have started.

 

[John D v2.0]

Agree with the above comments re squaring them up, i made a tomato shelter out of those exact boards and had to redo it because after a couple of sheets it was all wonky!
They are very good and clear boards although they get filthy just like anything else.
Regarding guttering on a flattish roof you will always get overshooting if you have a fall on the gutter, you can get bigger guttering if that's a problem or you could pack the brackets on an angled batten to make them tilt inwards slightly.
And regarding the comment about draining a while roof 3 sides into one outlet, that would indeed be against building regs. The manufacturers have guidance on area drained and outlet position.
Good luck with the project

 

[OldKettle]

Thanks for the recent comments.

There has been a delay with the delivery of the sheets I need to get started. Hopefully coming tomorrow or Tuesday.

The advice about laying the sheets is appreciated, and I do plan to lay a number down before fixing anything, and then fixing and checking as I go.

Regarding the gutter, I there wasn't any problem with overshoot when it was actually raining. The rain was fairly heavy, and was coming down 4500mm of panels, but still pretty much dropped straight. I suppose adding in some wind in the direction of travel might make a difference. If it is a problem I will certainly look at changing the angle, as John suggests.

 

[John D v2.0]

Regarding the gutter, I there wasn't any problem with overshoot when it was actually raining. The rain was fairly heavy, and was coming down 4500mm of panels, but still pretty much dropped straight. I suppose adding in some wind in the direction of travel might make a difference. If it is a problem I will certainly look at changing the angle, as John suggests.

Sounds like you've done your primary research and it's working well, thanks for feeding back.
Perhaps based on your experience I will dd a gutter to our tomato shelter, and run the downpipe into the water butt! It's something I've been meaning to do and not got around to just yet.

 

[OldKettle]

another point
2x1 tile batons are great and should be ok but are not structurally graded and can have many knots so will need careful selection buuuuuut------
---in this instance i think 2x2" timber would cosmetically look better as you are using substantial timbers
which way up where you thinking as flat would be least strong and upright will be hit and miss with the fixing

and another point you cant reach say 800mm away to put a screw in without something to lean or sit on

Thanks for all the advice on this thread. As @big-all pointed out, reaching across the polycarbonate was an issue.

There was no way that I could have done it from a ladder, so had to get some boards up on the roof, and then the installation was pretty quick.

I took the approach of drilling and screwing nearest to me, and then when the sheet was screwed down and more stable, I seemed to be able to lean on it a bit without any deformation.

I used a screw every peak at the ends, and where the sheets overlapped horizontally, and a screw every other peak everywhere else.

I ended up not using foam fillers on the purlins. Partly because of cost, but also because I personally don't like the look of them. Have had heavy rain since installation and the noise seems perfectly reasonable (although we also had hail, which was pretty noisy when stood underneath).

About 30m2 of the roof is down now, with another 10m2 to go.

 

[John D v2.0]

Perhaps based on your experience I will dd a gutter to our tomato shelter, and run the downpipe into the water butt!

Coincidentally I literally just came in from the garden from putting the above mentioned gutter and water butt!

Glad to hear you've got on well with your roof.

 

[big-all]

nice job i bet your proud
thanks for taking the time to show us the finished job it makes it all worth it