Tony L

Sorry, I'm too busy to dig that information out for you. I engaged him quite some time ago, although I have only recently received the full set of draft drawings that I was supposed to receive early in July. He came highly recommended by a prominent BH forum member.

Thanks, @Russell griffiths & @saveasteading. Pagurek offer this make up, below, as one of their suggested options. I will perhaps choose to upgrade from OSB to wood. I'm not keen on ply as it warps so much when it dries out after becoming damp. I'm happy enough with the standing seam above the 50mm air gap. It's the other aspects of the roof build up I need help with, please.

Well, yes, if you're not going to do it yourself, then you'll have to pay somebody to do it. You could get an M&E consultant, such as @Nickfromwales, who posts here a lot, to do the whole lot, or you might get one company to deal with CH & hot water, & a separate company to deal with MVHR, if that's what you're having. & if you're not having MVHR, I should think you just need to mention the trickle vents in the windows & give the spec' of the extractors in the bathrooms & kitchen. Somebody who knows a lot more than me will be along to help you out tomorrow.

If I increase to a 300mm I-joist, the U-value comes down to around 0.129 W/m2K. The arch tec’s roof is just 290mm thick, which is useful. The notes say it has a U-value of 0.11W/m2K. Actually, it says “0.11/m2K”, because he missed the “W” (Watts). Another thing he’s done, just to confuse us all, is he’s used label numbers that don’t correspond to the positions of the materials within the roof make up – so number 1 is the standing seam layer, on the outside, but number 5 (50mm air cavity) sits on top of the rafters (number 4) & the insulation between the rafters (number 6). Confused? I am. I think he’s drawn the Tyvek membrane on top of the 50mm cavity, rather than beneath it, & he hasn’t spec’d the battens for the 50mm cavity; should he have? Perhaps, 50 x 50mm C24 battens should be specified? I don’t know. I can’t find K107 & K118 in Ubakus, so I haven’t checked the arch tec’s 0.11W/m2K U-value for his roof design. I don’t like the look of the arch tec’s design. I don’t like the idea of cutting boards in between the rafters (ie relying on somebody else to do it properly) & I suspect the K118 might be off-gassing more poison than my design too. I think the arch tec’s roof may be more expensive (just on materials) than the design I proposed, & it will be significantly more expensive once the labour is factored in. Have I got that right? So far, I haven’t found time to get all the prices & work it all out. What do you think I should be saying to the arch tec about the roof make up?

I’ve had a go at plugging my I-joist based design into Ubakus. I couldn’t find most of the materials I wanted to use & Ubakus won’t let me have my battens for the interior plaster board running the other way from the joists, unless I pay a subscription, but this gives me a rough idea of how my 240mm I-joist roof option might perform:

I’d very much appreciate some opinions on this roof design please: I’ve designed a house myself (with no prior knowledge). I have planning permission. An architectural technician has recently prepared a full set of building regulations & construction drawings for me - ie one set of drawings will go to the SE for his input, then to BC for approval, then to builders. Now I’m working through the draft drawings, to make sure I’m happy with all the decisions the arch tec has made. My brief for the sloping roof sections was: standing seam on special SS membrane, then OSB, then 50mm air gap, more OSB, I-joists at 600 centres & Warmcel blown cellulose in between. I suggested 300mm deep I-joists or next size down (240mm), if we’re struggling to make everything fit (there’s a PP ridge height restriction). Also, I’d seen some of the arch tec’s drawings for another project (with phenolic everywhere) so I told him, to keep costs down, we should only use phenolic in one very small area where we need to avoid bulky insulation. He’s specified two layers of phenolic, over the entire sloping roof. My own (240mm I-joist based) roof design would be about 354mm thick – so, compared to the arch tec’s roof design, my design significantly reduces the space in two of my in-roof bedrooms, which don’t have dormers. The extra depth of the I-joist solution will be why he’s done drawn something that doesn’t fit with my brief. Here’s the arch tec’s design:

Here's Gordon, talking about his work, for anyone that's interested:

The prospect of a Section 75 claim, if your contract allows for payments to be made by credit card. Has anybody here ever made a Section75 claim? How did it go?

Thank you @saveasteading & @Mike. I got about half way through the video. You're right - it's not at all exciting. I'll watch the rest tomorrow. It hadn't occurred to me that a QS might help me evaluate the builders' quotes. There's a lot to think about here. Asking about the BoQ & cost estimate has raised more questions than I expected. I probably ought to leave this for now & focus on getting my drawings completed.

That's good to know - thanks. I've never seen a BoC, & I was concerned there may be pitfalls to look out for. I am very wary because, although I'm still in the early stages, I have been let down very badly by many of the people who have worked on my project so far & this has caused thousands of pounds of extra spend & months of delays. Yes, I will buy a cost estimate add-on as part of the QS work. I may make some changes to the design or specification, based on the QS cost estimate. & your point about the estimates is well made, although I will be asking for quotations, rather than estimates.

Thanks, @Dave Jones. For this, I guess I need the bill of quantities to be presented in order, with sub-totals for each stage. Some self builders have shared their BC/construction drawings, & this has been invaluable to me in enabling me to tell my architectural technician where he's gone wrong. I can't find an example of what you get when you've paid for QS, anywhere. If anybody would be willing to send me a copy of their reports, I'd be very grateful. Are mybuildestimate.co.uk a good example of a professional QS company, or are there superior professional QS companies out there? Any recommendations would be very welcome. Do these QS companies get almost everything right the first time they issue their reports, or is there often much work required by the client to get them to do their work properly, as has been my experience with my BCO/construction drawings?

Best on blocks, I'd say. We had ours installed by the dealer we bought the 'van from, & they told me to get the ground as level as possible & have plenty of blocks to hand. Perhaps they fine tuned the levels with off cuts of wood & old slates - I don't remember now.

if I remember correctly

I don't know which part of the country you're in, @boxrick. I've saved the details of a company in, Purley/Croydon, called Bespoke Guttering. They manufacture on site, from a roll, so you end up with a seamless gutter. They do fascias & soffits too. Presumably, they offer downpipes as well. I'm way off the guttering stage of my build, so this isn't a recommendation, but you may want to consider them if you're not too far away. Here's a picture from their website:

Well done for taking them on. I hope you win in the end. How did they force you to pay? Did this go to court?

Interesting. Thanks, I didn't know that. It wasn't one of my conditions, but they did put this in next door's conditions (for PP to demolish & rebuild - same as me).

Also consider that PP is often granted with a condition that the property will no longer have PD rights. This probably doesn't help you, @Leigh0403, but the best thing to do is to get your outbuildings up before PP is granted (assuming they qualify as PD & they're not going to get in the way of the main build).

Thanks for explaining your VAT reclaim, @nod. It's good to know they don't enforce the silly wardrobe rule, although a different inspector may have taken a different view.

The natural wood colour looks the best of those two pictures. It suits the house. Normally, I prefer black, but it needs to be on the right kind of house. With black, you can be confident it’s going to retain the same look for many years. With the natural wood, anything can happen – perhaps not, if you really know what you’re doing, but it seems most people don’t know (or perhaps the builders just don’t care). I don’t like it when natural wood cladding turns grey. I see a lot of wood cladding weathers badly & can look damp towards the bottom. I particularly dislike the “damp at the bottom” look I see on a lot of natural wood cladding – it looks just like a cheap garden shed to me, & that’s not a great look for a house.

You have no downstairs loo, other than the en-suite. Are you going to send your guests upstairs, or into the bedroom? Your enormous L-shaped hall is a waste of space. You could re-configure & have an extra room down stairs – a downstairs loo, & perhaps an office & cloak room as well. There’s too much glass in the bed room. A room that’s closer to square, rather than long & thin will always be better IMO. If you move the bedroom door towards the porch, you can make the en-suite twice as big, or make this room a downstairs loo, for everyone. You’d still have room in that big bed room for an en-siute. Which way is North? I wouldn’t worry about the internal configuration too much just now. The planners don’t care about how bad your internal configuration is, so just put in for planning to see if you’re going to be allowed to build a house that’s the size, shape & height you want. You may find they force you to build a smaller house or a house with a lower ridge height than you want. Once you have PP & you know what the constrains are, you can then spend time on the details, knowing you’re not wasting your time. You may need to put in for a non-material amendment, but getting these approved is easy compared to gaining PP.

It will grow on slates too, although it will likely be easier to remove than from a clay tile roof. Zinc works in the same way as copper, & would be my choice.

Probably not, no, but I'm past the point of no return now, so I will keep going, with a positive attitude, & I hope I will have changed my mind on this by the time the end is in sight.

Welcome to the forum, @JoanneP. My advice is: spend as many hours as you can spare reading through the history on this forum. There’s a lot to learn & I think this is the best pace to educate yourself. You will come across many success stories – so there’s the reassurance you’re looking for. Also, you’ll come across many stories of builds that have gone wrong – mostly because self-builders have been let down by the people they’ve employed. For example, my builder, caried out sub-standard work then, with the help of a solicitor, tried to force me to pay over £7,000 for work he hadn’t even done. The arguments went on for weeks. You could very easily find yourself in a similar situation. & the builder's not the only person who’s ripped me off or let me down badly – I could give you a long list. So if you’re confident you can stand up to these types of people, go ahead. If not, think again, because there are a lot of very bad people who are very good at telling wonderful stories about what they’re going to do for you then, sometime after you’ve engaged them, you realise they’re not going to make good on the agreement that’s been made & the arguments start – intense, lengthy arguments. Are you good at dealing with those kinds of situations? You may need to be.

Thank you for starting this thread off @Canski. I was thinking BCO & warranty inspector would do all the necessary inspections as the build progressed, & the SAP guy would have a quick look at the end & do some sums based on information I provided. I expected the process would be no more arduous than the last time I got an SAP cert for my rental flat. I can see this is something else I need to have a good look at before work recommences on my project

I can’t say for sure, yet. I had to ditch the Arch Tec whose drawings I already have, because they were so full of mistakes & he wasn’t good at correcting them, even though I was giving him plenty of help – so there’s no point in me telling you more about these drawings, because they didn’t reach the stage where I was ready to get the SE involved in the superstructure calcs (my foundations are already built). I engaged a new Arch Tec & paid him (on 19 May) & I haven’t seen a single drawing from him yet, even though I was supposed to have a full set of draft drawings at the beginning of July. Yes, I’m annoyed with him, but I’m still expecting his work to be good quality when I eventually see it. When I get the new drawings, I’m envisaging my thick wall, with the blocks laid flat, will run up to the height of the first floor, then there’ll be upright blocks on top of this, flush with the wall beneath on the side with the stairs, & running all the way up to the vaulted ceiling/roof. If the SE looks at the drawings & says we need to make a change, & go all the way up with the blocks laid flat, I don’t think this will create too much extra work for the Arch Tec. I’d rather keep to upright blocks at first floor level, as blocks laid flat would eat up an extra 115mm of bedroom width, & cost more.