Nick

I havent... will do though! Is it something you can install yourself? The reason im quite liking the timber I beams is that although there is a lot of work in fitting them, they're lightweight enough that a few people can do it without too much need for plant or expensive access.

I did consider it but the ply is doing 2 jobs for me the way its drawn now. Stiffening the joists and giving me something to fix to from the inside. If i were to put it on battens id lose the Stiffening of the joists and if i were to put the plasterboard on battens it would be harder to fix to. Keen to avoid adding more cost with another sheet of ply or OSB although not the end of the world. You think there would be an issue running services through the main cavity or just inconvenient? Also any suggestions on where to put the VCL? Can i just tape between the joints of the external OSB, and should i be worried about the screws for the battens going into the boards?

Morning All, As a few of you may already know, I've just started planning a build which is going to center around a huge double height room (8m x 10m floor plan minimum). Main priority is to get no-frills well-insulated space on a tight meter-rate although good acoustics would be a bonus. It seems so far the only way I'm going to get this amount of clear, open space without huge costs (although I may well be wrong), is a steel portal frame construction which there is amazingly little info about on the net. I'm still reading everything I can find and pricing up different possibilities for the main structure, but it seems the key problem is going to be insulating the steelwork at ground floor level to prevent cold bridging and protecting it from fire. I've taken a lot of the inspiration & methods from the "barnhaus" design from a couple of years ago which was also a steel portal frame, but the walls on that build were 450mm straw bale and built inside the steels from what I can tell. That would lose me 500mm of floor space all around and also I'd rather stick to a design that will be simple for builders to put up as this will help my chances of getting a good labour rate for the bits I can't do. The attached is my first attempt at a wall design. I haven't started looking through the regs in detail yet and although I do work in the construction industry, I'm a total newbie when it comes to anything other than glass. All I really know is what I've read in the last couple of weeks so would appreciate your help in picking this apart and understanding a better way to go about things. Open to all methods/materials/ideas at this stage. Wall Detail A.pdf Construction is (Inside to Outside):- 12.5mm Plasterboard 18mm Ply 300mm x 97mm JJI Engineered Timber I Beam. 2x 150mm Rockwool In Between Studs. 18mm OSB3 25mm x 50mm Treated Battens 20mm Rainscreen Cladding (Rough allowance as I don't know if it will be timber, aluminium e.t.c.) Based on the JJI book, this should achieve around 0.12 W/m2K. Could possibly add some 50mm PIR in there to reduce further and smooth any cold spots from the timber. My very rough costings show the raw material costs at about £70/m2 My hope is that by putting the steel in the middle of the wall and allowing enough space to pack around it with 60mm PIR (possible along with intumescent paint), I can fire-protect and insulate it in one go without losing too much internal space. By using Rockwool instead of PIR, the acoustics should be slightly better although there is no cavity or decoupling so I don't know how well it will really work overall. There will need to be vapour layers in there somewhere which I haven't drawn. Thoughts please?

Door knocking the neighbours and telling them face to face about your plan is an excellent idea. Will add this to my ever increasing list of notes

Thanks very much. I'll definitely be asking you all about build methods later on tonight as I'm in serious need of some help detailing the floors & walls.

There are a lot of things that can be done but which aren't in the fabrication manual / aren't supported by software and may fall outside the scope of what has been tested for weather performance, security, e.t.c. Then there are the weird shapes & forms - you can never really know how well (or if) they will work until you make them. Glazing companies will be hesitant to make things like this as they take 10 times the labour and effort of a standard product and if you make the slightest mistake or miscalculation anywhere along the way, you have to start again from scratch and end up doing the job at a loss. They'll also not want to take any risk on something that will later have to be serviced on site. If you're looking to buy something non-standard and don't want it to cost a fortune, the best thing to do is sit down with whoever deals with technical/production, ask them what the issues are and let them know you're willing to accept no warranty or limited warranty, and you're aware there may be some compromise on the finish or the operation because of the complexity (assuming you are). Better yet, buy square windows in a stock colour!

Cheers Nick. I'm rubbish at plumbing... honest

Big help, thanks. I know what you mean about public transport inside M25 - going from NE to NW london used to take 90 mins easily by tube. Between M1 & A1 could be a winner if 250K for land comes out as do-able Am doing the "book writing" method with my build cost at the moment, re-writing it again and again seeing what I can take out or make better. First costing was way over budget AND relied on me doing way too much DIY to be practical. Second revision was just as over budget but at least allowed for enough labour to get the main works done. I reckon if I can get to a 20th revision I might have enough leftover for 200-250K land

I'll ask at the next club meeting....

Cheers! The cornerstone of the build we want is getting a very big double height room (8m x 10m minimum) - and having enough room left over for the two of us over two stories in the remaining footprint. Think we could work with a relatively low ceiling height across the two storeys but the footprint is going to be the key struggle. Back to stressing about the build costs - will have to leave stressing about the land until later a bit later

Thanks for the insight. Definitely have no plans to spend any of my hard-earned on anything other than land that has planning permission and access to services in writing. Have heard of far too many people being swindled. Still relatively young so I'd rather bite the bullet and look at areas I can afford instead of living in a dreamworld...

Good tip, thanks. Would it be a struggle to get permission for a 2-storey house when replacing a bungalow or does it all depend on neighbours / proximity?

We don't do conservatories and this one of the the main reasons. Thankfully they are dying out fast

Thanks Steam (sorry to call you that by name but nothing else suggests itself ) Googling it now I found a site that seems to have good comparisons :- http://www.gbpn.org/databases-tools/bc-detail-pages/england-wales# You'll see the UK is at a max u-value of 2.0 (or 2.2 in some cases) for new build whereas Germany, Finland, Denmark, Sweden, e.t.c. are between 1.0 and 1.4. Might not seem like a huge difference but in practice, meeting those u-values means using 44mm triple glazing with Argon fill and warm spacer bars as standard for a lot of products. In the UK we have a fetish for slim windows (sightline-wise). Our slimline open-out systems struggle with the depth and weight of triple glazing and don't really have Uf values low enough to take advantage of them in any case. To use triple glazing effectively you need to move up to a bulkier window with foam inserts - these don't match the look of our old steel and timber windows so even if you're not in a formal conservation area, your house will stand out a mile if you fit something like this when all of your neighbours have Georgian windows with their hundreds of tiny squares. A planned move to a 1.4 minimum window U-value in Part L was delayed a couple of years ago because of limiting factors like this though the day is coming.... Regarding u-value calcs, maybe this is something best done in a separate thread of glazing questions as it is a bit involved?

Thanks Peter, Truth of the matter is I'm not sure yet - still very new to this. Would love somewhere in North London, Herts, Berks, e.t.c. near to where I grew up but the land prices seem out of my reach. Then again, I'm still doing and re-doing budgets and cost breakdowns to see just how much a house we would realistically be happy with will cost to build, so I can figure out how much I can afford to spend on land. Bit of a chicken and egg situation. Is it the done thing to (roughly) design a house and then try to find a plot of land to build it on or does everyone go out and find land and then build the best they can on it? I think ultimately If getting a house that we love means looking further out above the green belt then that's what we'll have to do. Motorway / Rail links would still be handy though. If you have any suggestions for anywhere along the M1 North of Watford that might actually work for a reasonably affordable build with modern construction methods I'd love to hear them.

Thanks Joe. As much as I'd love to help, unfortunately wooden windows are the one type we don't currently fabricate. It is a whole other manufacturing setup compared to Aluminium, uPVC, Steel, Bronze, e.t.c. and very hard to compete price-wise with the Eastern Europeans and their infinite forests. Would also depend on where you are located - we are based in London & Herts mostly servicing the lower half of the UK so may not be cost effective for someone building up North & vice-versa. With regard to discussing the company specifically on the forum, it's probably best I don't, forum rules aside, as I don't want everyone on here to think that I've just joined up to promote myself. Plus "you" self builders are the most nightmarish customers ever and as I'm Technical, your wacky schemes and sketches will only end up on my desk tomorrow morning If anyone does need help getting prices on a trade basis I'd guess the best thing to do would be to message me privately and as long as it's within the rules (??) I'll do my best to assist.

Thanks Alphonso

Ian, I can but I promise you you'll find it very boring Ultimately the British profile companies always lag behind the German and Scandinavian countries by at least a few years. Their building regs are more stringent and their glazing manufacturers tend to be larger, working with more automation and producing greater volumes. British glazing companies are generally small, with a workforce that have learned from the previous generation without much formal training at all, and are therefore very resistant to change. Real changes only get pushed through by updates to the building regs but even they have to water down their requirements as the bulk of the UK fenestration industry just isn't capable of supplying and installing products to the standards of our counterparts on the mainland. I'm lucky to work at one of the few manufacturers in the country that do make attempts to innovate and push quality but it is an uphill struggle. The existing UK housing stock is so poor that putting triple glazed SI windows in will never pay dividends and we have so little land for new build that developers are only interested in building to the minimum spec acceptable. What attracts me (and I imagine a lot of people) to self-build is that it's a rare opportunity to build something properly with an eye on long-term cost effectiveness instead of just quick profit. Oh, and thanks for the welcome !

Thanks Jack. You'll see that I have the original "Nick" username and am therefore at least 1 letter more "Nick" than any other imposters that may be around

Afternooon All. I'm Nick - me and my fiance are planning a build somewhere in the East/South-East of the country (where exactly pretty much depends on finding an affordable plot) in order to create a huge double-height studio space as part of our home. We've just started the process of budgeting and putting together our design brief. We're both hugely excited about the possibilities and keen to learn more about the practical side before we get going in earnest. Have already found some great advice here from reading through old threads and I'm sure I'll be starting my own threads and pestering you all for input on a hundred different things before long so apologies in advance for that! I work in the glazing industry at a company that manufactures, designs & installs just about every type of glazing you can imagine (standard trade, all kinds of doors, curtain walling, minimal, structural, e.t.c.). Currently a director but I've done just about every job there is along the way. As a result I'd say I'm pretty well versed in most things a homebuilder might come up against glazing-wise and I'll be more than happy to give some technical or cost-engineering input to anyone who might need it if you send a message or point me towards your thread. Nice to meet you all.