Thorfun

thanks, that makes sense. I ask because I have a quote from a groundworks company that is just using Stylite EPS and building the slab and walls like yours so it's good to know that it worked for you! I've got no issues with it as EPS is EPS as long as they're ok with it and it all connects well I see no benefit in paying extra for an 'engineered' EPS solution.

@Bitpipe I've got another question for you on this (sorry!). on your basement did you use a 'manufactured' solution, e.g. Kore/Isoquick/AFT etc for your insulated slab or was it just bought EPS and fitted together by yourselves/groundworkers? I know I've read all of your posts about your basement but this is one detail I can't remember you mentioning.

yep, and this is making me reconsider our (I really should say 'my' as SWMBO doesn't really care and just wants the ****ing house built!) target U-values. I'm wondering if I should reduce the 80mm PIR to 50mm. this will change it from approx 0.12W/m2K to 0.15W/m2K and save quite a bit of money. so I'm trying to weigh up the costs and make a decision. but part of me is thinking I don't want to add more insulation at a later date and if/when building regs start to mandate <0.15W/m2K i'd rather our building still conform so maybe just go low now and not worry about it in the future.

it would be interesting to know the thickness of the ICF walls to get you to 0.12 W/m2K as that's my target U-value in our timber frame and our walls are 140mm studs with mineral wool between the studs and 80mm PIR on top so 220mm (not including VCL or service void which the ICF won't have either). I would reckon that ICF walls would need to be nearer 400mm thick to get similar U-values, but I might be wrong. But I do think TF will get you better U-values with thinner walls simply due to the fact you can put the insulation within the wall whereas ICF is on either side. But, as has been said before, U-values aren't everything and every one needs to make their own decisions on their requirements and ideals.

thanks @Bitpipe and @HerbJ. very useful explanations. I've already requested compriband from Norrsken it's just the window reveals that I'll need to double check on but I'm glad I've got confirmation from both of you that my plan of action will work! I need to save money and installing the insulation myself is one way of saving money but it will take me time and I don't want it to hold up anything external to get the building watertight. hopefully this thread mini-hijack is also useful to the OP @Suffolk_J as it sounds like it's the same route as me.

ahh....ok, that would account for the OSB finish internally. I guess that's different to me installing frametherm between the studs and PIR over the top. I was pretty confident that the windows can be fitted to the TF as simply an open panel TF without insulation but there is now an element of doubt!

thanks @HerbJ. Did you not go for factory fitted insulation from MBC?

hey @Bitpipe. quick question on this statement. if we're doing the insulation, VCL, service void etc ourselves do we have to wait until that's finished before getting the windows fitted? from your post it sounds like you do but I was working on the principle that the TF company erect the shell and we then get the windows fitted as soon as possible after that and I can then work on getting the insulation installed etc at my leisure. but you've put a doubt in my mind now as to the order things are possible.

Welcome. I had similar criteria to you when I started looking for TF manufacturers and my decision process can be read here: but, basically, you should get multiple quotes from multiple companies and then make a choice on those. it's not easy and we did eventually choose to go with Flight Timber and, so far, they've been great but we haven't even broken ground yet so I can't comment fully on them until we get to the stage that the TF is erected (fingers crossed in about 3 or 4 months time!). once that's happened I'll be happy to share my experiences with them. but I'd say they're definitely worth a shout for a quote and they're based in Essex which isn't a million miles from you. good luck.

I hope you didn't get your plumber to fit them.

thanks for this reassuring post. we have our FFL designed around an anhydrite screed so would've been a real ball ache to change it! we will proceed as planned with the anhydrite. cheers.

seems to be a bit contradictory here @Temp. sounds likes you can use Anhydrite screeds if you want to tile then, you just have to ensure that the laitance has been removed, which should be part of the service for installing the screed. plus, it seems to be recommended to use a decoupling mat under floor tiles so, in theory, the tiles aren't being laid on to the screed but to a mat on top of the screed. so does the "avoid anhydrite screeds if you are planning on tiling" quote still stand if the laitance is removed and you're using a decoupling mat?

I have been quoted £7k for my new 3-phase connection, mind you nearly £2.5k of that is council charge for a TTRO (temporary traffic regulation order) and £1k for UKPN to manage/design the road closure. the actual 3-phase connection was £1500 and about £2k to dig and replace the trenches under the road and verges. "Description of the Works to be carried out by UK Power Networks: Quotation is for the installation of a three phase underground service from an overhead line. This includes excavating laying and reinstating of 7 meters of the grass verge. This includes 4 meters of excavation laying and reinstating of service cable in the road. This includes an extra 10 meters of three phase cable and ducting. This includes a road closure and also council costs of a road closure. This also includes a letter drop to residents." For us the £4.5k to not have overhead cables is worth it. p.s. our is zero rated VAT

just grind the screed. ? you know that if you don't you'll look at the bodge job you end up doing and regret it. (although Amtico is a nice product. had it in the last 2 houses in places)

so the line I've circled with red on this plan that's from the land registry: sure looks like the fence line circled red on this map that you said shows what was gifted to you: so, if that is the case, then that looks to me like the land registry map is wrong when compared to what was gifted to you. I don't know how to resolve that but I'd be checking the fence line to see if it is the case and then seeking legal advice as to how to rectify.

Just as a word of warning on those suggesting future extensions. We had our PD removed as part of our planning approval so future extensions may not be so easy. it may not be the case for @Mulberry View but you never know what planning will do.

I think it's a lovely design and fits in well with the plot. for an initial concept design I'd say it's a great start! but, obviously circumstances differ, when our architect said he was concerned about the budget for the size of the house we're planning I just said we'd build it in stages and finish bits as and when we need them. e.g. the basement won't be finished until way down the line and the room above the garage can be done at a later date. etc. that way we managed to convince that we could build the house we wanted for the budget we have. either that or he just gave up caring! at the end of the day, in my opinion this is, it's not the architect's responsibility to get the house built to budget but yours. so if you think you can build a bigger house for your budget then you need to make sure the architect accommodates those wishes. looks great though. can't wait to see how it all pans out.

I wouldn’t say extra long, no. The plant room is front and centre in the property so the ducts go straight up from the unit to a manifold on each floor for distribution.

Ok, cool. So not really something to worry about if a spare extract is not available! our unit is going in the plant room in the basement (assuming we can afford a basement that is!)

I'm going for the same setup that yourself and @joe90 have then (following the yellow line approach of the OP). interesting about the MVHR extract, I hadn't considered that a requirement and the MVHR designer hasn't designed one in either. if there isn't an MVHR extract how would the moisture be extracted? what sort of a problem could it be? just wondering if I can make sure I have a spare port on my MVHR manifold for the upstairs that I can take an extract to the loft or if it's a little excessive and worrying about little.

if there's one thing I've learnt in my brief self-build journey so far it's that things always take longer than you expect/want them too! that includes quotes.

I don't like commenting on other's designs as I'm definitely not qualified. my comment is that if you're going to use an Architect and turn up with a plan like that you're basically asking him to draw up that plan and thus removing any extra design value that the architect might bring. I would suggest going to an architect with a brief of what you want and letting them design it without any preconceived ideas. but I just wanted to say that I remember how exciting we were at this stage of designing and tried to come up with ideas, plans, layouts etc so I know how hard it is not to want to get stuck in straight away and put your ideas on paper. Good luck with it all.

Welcome. Sounds like a great project. Like @joe90 said, post questions in the relevant sub-forum and don’t worry about thinking you’re asking too many questions as we’ve all done it! I would suggest using the search function for each question topic you have first as I found there was a thread already started by another user that you can add a question to if appropriate. You might find that your question has already been answered. At least that’s what I found.

sorry for the hijack but I'm planning on running the VCL up in to the loft and on the inside of the insulation between the roof beams so downlights in the first floor ceiling will still be within the airtight layer. is this a valid solution to this problem? Also means that the storage space in the loft is within the insulated envelope of the house. Think I read this is a warm loft rather than a warm roof.

I got quotes from various sources as well but, in the end, Protek were by far the cheapest.