saveasteading

Isn't the attraction of glulam , other than the long spans which you don't have, that it looks pretty? Painting and screws kind of lose that. OK I think I'm going to let you get on with it. But good luck.

Except at the ridge. You know not to put anything through it, but lots of people don't, including Architects. I only have horror stories and dire warnings to go on , as I never did one. We had it in our portfolio of options, and no client ever chose it, based on cost and the warnings about function. We also offered it with sliding fixings to allow for movement as otherwise it can ping. Yes do it yourself. Forget degrees and stick to the more useful horizontal length , height difference and slope distance. you can do this yourself with a tape and a long stick. 430mm height difference over 9m ( 1 in 20 or so) would indeed be effectively 'flat' and not a great idea in metal cladding. Come back when it's worked out.

Whether mounted over or inset, you will see solar panels, not metal roof. As you imply it is expensive I assume it is standing seam. I would never, ever put any opening into standing seam: it's sole purpose is appearance and its main problem is sealing at joints and interfaces. I avoid openings in any metal roof but SS is an issue. Hang on... 12 degrees is about 20% isn't it, or one in 5. So a 9m span has a rise of 1.8m, not 430mm. Am I getting confused?

That's why I suggested bolts and nail plates. Add glue if you want and the bolts will pull it tight. But even if the glue fails completely it will perform as well. Nailplates: I've used the wrong term. I had in kind these, called plate connectors but meant that they had spikes on both sides to join the touching faces. But these linking the tops and bottoms would work. I'm assuming it's out of sight!

12 degrees is far from flat. Not just for insurance but anything. Most steel buildings I built were 6 degrees (10%). That required careful detailing and sealing. 12 degrees is fairly normal. steeper than that is very steep for metal. So yes, you have the wrong supplier. Do you really man 'in-roof'. It is easier, safer and cheaper to have it mounted on the surface.

There was a time when dubious quality was being imported so it makes sense.

If your project is big enough then you will get an account, subject to credit checks or paying as you go. They may say trade only, but just ask for the manager or sales rep.

I'm intrigued though. I've never been asked for one in hundreds of projects. Was it a keen young bco?

Who me? Yes and I'm quite good at it. But deadlines, the 4 hours a day stamina, and the family veto are the issues. It's a point though that perhaps we ask elsewhere. I expect the same from any floorer except that 'abort and charge' threat.

@Alan Ambrose points are excellent. Most builders have one trade account because of convenience and that a decent turnover gets good service. That might well not be the best for price. I happen to be very happy that our chosen merchant always gives the best or near best value without ever haggling. All we buy elsewhere is specialist stuff or pallets of eg screed where the middle merchant is missed out. That can save 10%. I forgot a big one. Cashflow. You will be paying 20% vat and not get it back until your claim at the end. Materials are typically 40% of a job. The contractor reclaims vat every 3 months so also has cashflow and admin issues. They are entitled to more than what you call a "tickle". I'd want 20% on top. So our decision us that we are buying materials , having long experience of best value. But the plasterboarders are supplying their own, as this reduces handling, waste, (and skips). Ditto electrician and plumber for their tech stuff but we buy the appliances.

I made a pergola with a Glulam equivalent. The main difference being that this was in Spain. So termites and heat were more the worry than wet. After 7/8 years it's good. In UK conditions I'd ve worried about the effect of prolonged dampness on the wood and the glue. So my suggestion is to get treated timber, preferably choosing the lengths yourself. Now would be a good time because they might be dry. I'd want to set them aside with air flow and a cover for a few weeks. If they distort then get them changed because they are not supposed to. The timber association TRADA says they should be kept dry but no merchants pay any attention.... I had 50 big pieces exchanged without protest. Then bolt them together at 500mm cc max and perhaps add nail plates.

A letter from whoever saw it being built, ie SE or Arch, saying that it isn't usual to require this and it was 5 years ago but from visual inspection at the time this was industry standard material. Bco can file that.

No. Cash would come back in a big way and not be declared.

I rescued some packaging from the skip so I'll see. That's the skip which is not to receive cardboard or timber and especially not empty boxes! But they 'forget'.

Reminder to self... look at the socket for the cable before proceeding any further. The antenna was fixed far too early and is now a nuisance. That's a downside of family democracy.