TerryE

Hi, my main comment is that you've really started to ask some pretty fundamental Qs at too late a point in your project. You seem to have a design that includes a reasonable thermal spec as designed goal, but I am not sure that you or your architect how looked at this from a total system perspective, and at this stage any fundamental rebalancing could involve costly rework so I suspect that you will have little wish to do this. There's over 8,000 topics/threads on the site, most with 10s many with 100s and one with 1000+ posts on all sorts of detailed aspects of the why, hows and why nots of building your own home. There is a lot of gold to be mined if you are willing to use the forum search facilities, do the research of existing knowledgebase and ask the right targeted questions. Like any forum there is a spectrum of users giving advice and opinion here. At one end of the spectrum you've got people that clearly are "shooting from the hip" and not doing the necessary research (or hiring competent experts who are able to do this on their behalf), and their blogs and posts are horrifying to read. At the other end you've got individuals who have come through this process with a house that they love; that performs to their expectation and that was build in a well controlled manner. I am not going to give examples of either or the middle ground, but I do suggest that you research some of the blogs and frequent posters to rank the value of their advice in your own assessment, and weight this advice accordingly. Anyone who builds a house has to deal with the same issues: planning and other external constraints; the feasibility and practicality of their design and its build process; the vagaries and quality of tradesmen and suppliers; financial management of the entire process; and the integration of all of this to achieve an end result that they wanted to achieve. I suggest that the main difference between the two ends of this user-spectrum is the degree to which individual self-builders approach this process. IMO, the best way to solve a problem is to avoid it in the first place by design. The next best way is have sufficient audit and quality checks in place to detect each issue as absolutely early as possible in the life-cycle and at a point where you still have some freedom to identify options and workarounds that you can still implement and at a modest cost impact. The worst is to be left with a fait accompli that will be costly to mitigate and will constrain and annoy you for the rest of your time in the house. As I write this, I am sitting in my home office / 2nd guest bedroom on the 1st floor of my new-build that we have now lived in for the last year. My wife and I are unreservedly delighted with our new house. I am sitting in my shirt sleeves in a room at about 22°C (a personal preference), but we don't have any heating on the 1st or 2nd floors; I do have UFH throughout the ground-floor, but this is currently run off a 3kW immersion heater element that comes on for about 8 hrs a day (mostly E7 cheap rate) at current outside temperatures. OK, achieving the spec to do this added maybe £10K or so to my build costs (if that) but we saved as much in not having to have a gas supply, a conventional CH system and radiators everywhere, and the annual maintenance costs for the same. In terms of thermal design, IMO you need to start will an intimate understanding of the macroscopic thermal performance of the house and what makes up the pie chart of heat losses, because this impacts so much one the costs and characteristics of the build. @JSHarris and I amongst others have blogged and posted copious details on this. It seems that your design is out of balance, e.g. your floor has too low a U-value. Are you planning to use MVHR, what is your fenestration design goals, etc. With these sorts of U-values, you are going to have a pretty conventional house in terms of running costs and heating solutions. Is this a deliberate decision? Why have a garage? You will have less parking capacity and more costs with one. Why not drop the garage and put in an electric gate to secure the property instead? Your floor profiles don't allow UFH unless you have in-slab UFH. This is entirely doable (and we have this), but IMO most builders are not competent to do this to an acceptable standard. The L-shaped design has a large surface area for the enclosed floor space. I can see that your plot geometry really makes it impractical to do otherwise and I assume that you are locked into a approved plan, but this larger surface area exacerbates U-value impacts. There are other downstream comments that I could make, but I'll defer them for now. Time to do some reading of blogs and topics covering some of these points, I think.

We average about 70% off-peak in the winter falling to maybe 45% in summer, so in our case it's an absolute no-brainer. OK, we have no PV thanks to the planners, and we still haven't scheduled the ASHP selection and installation, but E7 is a no-brainer at the moment for us. As J says you do need to tune your lifestyle to optimise E7 usage. We do our bulk UFH, SunAmp, washing and dishwashing during off-peak. We accept that there is a ±½°C ripple (at most) on the house temp because the bulk heating is done overnight,. An example of one change that I have made this last month where if the average outside temp drops below about 5°C then we need more than 7hrs @ 3kW to keep the house temp in tramlines is that I have a small oil filled electric radiator which I leave on low on a midnight - 07:00 timer in my study adjacent to the first floor landing. This acts to top up the house heat using E7 rather than peak and also helps rebalance the small ground floor vs upper floor temperature difference that occurs when the outside temp is low. My house heating algorithm is adaptive and so just compensates for this secondary heating source.

Ian can you explain what you mean in the first sentence? I've read through it a couple of times and am still confused about the context. Has the plot PP for two houses or one of 300m²? Or one of 300m² + one other? You are mentioning construction techniques such as ICF and box trusses, but this will seems out of order to me. What are your requirements and financial constraints? Doing a self build is in general as expensive or more expensive than buying a comparable new build because it is a one-off and you don't have any of the economies of scale that a standard builder will have. Like many here who have been through this journey, it is extremely stressful and hard work. If all goes well then you will end up with property that is built to your specific requirements and attention to detail, so the self build premium might prove worth it for you, but this isn't the case for a build to sell. The other great complexity here is the financial management of the entire process, it's optimisation and working within imposed financial constraints; again this is really hard for a single self build but the issues more than double for a two plot development. We were extremely lucky in our financing and in retrospect we could not have found a better deal, but finding it also involved a lot of work and stress. We had a village setting and decided to split our plot and build a retirement home then sell our previous house. This sounds simple in principle: get financing; live in the old house; build the new one; sell the old one and move in. Again in retrospect, the dice couldn't have rolled better, but the whole process involved sleepless nights and so much work. The cost of build invariably mounts above your initial innocent budget and so it is really hard completing within your in-place financing. In our case, our old house was a 17/18C farmhouse in the centre of a village (the plans had been sold and converted to an estate that lay to the back of the plot long before we bought it) so it was a niche sale that really needed the adjacent new build complete to be sellable at anywhere near the market price. Lots of catch-22 variations in executing this. Luckily we are retired and had the time and skills to do a lot of the work ourselves which meant that we could offset costs and keep a very tight control on quality. My advice is to sort out the principles first and make sure that they are derisked first. What are your requirements? How are are you going to finance them? Etc. A few specific points: The second plot. As I said doing this yourself will double the financial burden and more than double the stress. Another alternative is to sell it with outline PP and leave this to a builder experience in doing such 1-off infill developments who can finance and manage this. However this has risks in itself as you no longer own and control the second development and you might regret having to live next to the outcome. Future prooofing for loft conversion. This rarely makes sense IMO. If you are going to do this then do it properly at the initial build stage. Incorporate the space as a warm space within your approved plans, including access, fenestration etc., but leave the space unfinished - a blank tablet. This will add little to the cost, but far more to the value of your house and give you more future options if you find yourself with an extending family or even a stroppy teenager that you need to share the house with. A ridge RSJ and full structural roof joists plus a couple of roof lights will only add a few £K to the overall build costs. Where are you going to live during the build? For most people using the capital on the existing property is an essential component of financing the new build. We had fully paid off on our farmhouse, and I had enough retirement income to get a mortgage on it to finance the whole project and a small BSoc that were happy to do this, but many members here end up living onsite in a caravan for most of the build (and some plan in an early fit-out and "legal inhabitation" of a couple of rooms to get out of the caravan). We started our journey in 2013 with an initial decision to split the plot and self build. In retrospect our initially invisioned timescales were laughably naive. Add at least a year to your anticipated timeline, and then work out how this can be best used to derisk and to optimise. Crashing timescales invariably costs £££s and lots of them. So work out all of your major issues and risks and have sound outline solutions in place as soon as practical. Impossible projects never become suddenly possible by magic. Doing a self build is a bit like skiing with an avalanche behind you.

Or it can slide, of course. And IIRC, you don't need a wheelchair-accessible bathroom in a new build, just a toilet.

Uaarrgh, health and safety again: counterweights, safety sensors and cut outs, etc. Now there is a risk of your wheelchair owner getting "terminator"ed. You can get some flush mounting rotating door mounts that typically pivot ⅓ ⅔ but the total door would end up about 1½ m wide if you want the opening to be wheelchair accessible.

So Debbie doesn't track and monitor your threads then. ?? In the Jan's case, it's more case of involvement / genuine interest in the content than any Stalinist control, but I still need to remember that anything that I say might be read and picked up

They look good on films, etc., but I suspect that making one in real life will be troublesome. A lot of firedoor-rated sliding door gears will be heavy duty enough to carry a light book case, but if you want it to carry non-trivial capacity then you will need a bottom rail as well or some form of casters if you are rolling over a hard surface such as tiles. There are also lots of fun details such as the wall to the side of the case will have skirting and the door will need to clear this, plus you will have a top rail to the side that you will need to hide somehow if you want the door to be "hidden". The sliding case will not only need to slide, carry its load but also have extra racking stiffness to say structurally sound during opening and closing. So entirely doable IMO, but the devil is going to be in the detail and it is going to involve a lot of work. There is also the safety issue as well -- you need to be sure than said door can't come off the mount and flatten said person in the wheelchair. This is one where if you don't want to say "no" to your nearest and dearest, then you "future facilitate" the project by having an simple opening and leaving the wall to one side clean with the suggestion that "we do the door itself a year after we've completed the house, moved in and done the million and one other jobs that really need doing".

Too late for me, now. Sorry. I had to toss the dice, and chose. Peter had already given me the contact details for his guy, and he was willing to do the work, so I agreed. It wasn't worth wasting their and my time to shop around further. I've just sent him the data pack. I guess it depends on the individual BInsp, and no doubt some will be hot on double checking, but for ours this seems to be more of a tick on the box exercise. I just need the EPC lodged and the reports need to show Part L compliance. What I find so frustrating here is that the likes of the main construction firms use internal company-employed inspectors and template based SAP and EPCs: this a type 22 house so the EPC is X (even though a third of the insulation might be missing). Anyone taking even the most cursory look at our house can see that it will be top percentile performance, so the certification is simply a paperwork formality. I know that we try to avoid overselling vendors and professional services so some of use tend to PM these sorts of contact info, but especially in this sort of case it would really make it easier for new self-builders to find out a list of SAP/EPC assessors who are willing to work with self builders who have done their own as-designed or whatever. I know how to use the forum search features, and did do a trawl of post topics on this and to be honest a lot of the useful stuff came up in off-topics where the thread wandered into "you will need your SAP / EPC" asides, but just being able to look at an aggregate summary would be great.

Jeremy, it was a worthwhile exercise for me, but this comes with a heavy health warning: the house building going on in our area (MK / S Northants) is crazy at the moment and local SAP EPC consultancies just aren't interested in the hassle of doing the as-built if they can't do the as-designed / as-built bundle. So finding someone involved research and ringing around, and in the end I took up @PeterW's referral. This wasn't a cost saving for me, and I still have to follow through to submission. I don't care what the result is so long as we hit minimum Part L compliance. I don't want to waive a A rating round or whatever. I am going to be living in the house hopefully for decades, so the certification itself is purely a tick-in-box exercise for me. I know how my house performs in reality and this is in the top %1 of housing stock in the area. I also really object to my house getting marked down because our planning officer told me that we wouldn't get planning permission if we put PV on our roof because it wasn't in keeping with the street scene.

@Hecateh, that's why I advised taking a break and replanning. Like you we split our plots and got pretty cash strapped before we sold the old farmhouse and moved in. Once we had, then we had enough cash to sort out a load of jobs, but the trick is to triage: a dust-sheet pinned over a door opening will give privacy and keep out drafts etc... Only make the stuff that is time critical high priority, for now. Don't rush the stuff that you don't need to: less stress and a better chance of getting a good job done.

Unfortunately the as-designed SAP + EPC was submitted the the BInsp just before the frame went up.

Thanks, guys. I will get my s**t together and ring around tomorrow. I've realised that it is just not worth doing online contact forms or exchanging emails: the two companies that I started email exchanges with didn't even bother with "sorry no" after the penny dropped that the house was already built. They just didn't reply. At least I got honest and quick responses on the phone, and so realised what the issue was and avoided wasting everyone's time. The crazy thing is that this is just a bureaucratic exercise. Because I have been so involved in the design and built, I doubt that 1 in a 100 new houses actually as-built come anywhere near mine in terms of true energy performance. But reality isn't the issue; it's the paperwork and a dose of 20-20 hindsight.

@JSHarris et al perhaps you can give me some advice on next steps and where to go. During the as-designed stage I basically followed the path trod by Jeremy and did the as-designed calcs myself using Stroma 2012. I submitted them to my BInsp without any comment or feedback. All good, so far. I am now going through my checklist for my last BInsp sign-off, and am trying to find a company to do the as-built SAP and EPC. Now the catch-22, I've tried 3 local companies to get my SAP and EPCs and none are interested in doing the as-built if they haven't done the as-designed. Shit. So the purpose of this topic is: To advise other self builders to avoid the approach that I took: saving a few £100s is really not worth the hassle: commission a professional firm to do both. I believe that the main issues are whilst there is nothing in the regulations preventing a self-submission of the as-designed, the as-built EPC must be registered etc. and so this can only be done by a registered practitioner. There is also a traceability requirement between the as-designed and as-built and the SAP/EPC pricing is so competitive that it is just not worth the hassle factor for SAP practitioners to do this for as-built if they haven't done the as-designed. To ask those members such as Jeremy if they can recommend an assessor that is willing to do the as-built only -- or if anyone knows of an online service where I can submit my worksheets, etc. Price is a very secondary issue now. It's minimising the hassle to getting the sign-off that concerns me

@Big Neil, designing a passive slab is not something that should be done on the "back of a fag packet". If you get it wrong then you might never get the BInsp to sign off on it, and more to the point your house might be structurally unsound. You really need to have this done by an SE experienced in slab design. So you need to find such an SE to do this. If you want then a few of us have constructed our houses this way and can give you our SE details. There are too many variables here for there to be a stock answer. For example our SE required us to do a soil survey because the type of base materially effects the under-slab preparation: whether it is clay or sand, and the sub type, moisture contents, proximity of trees, etc. Any differentials across the site can be critical to whether a passive slab can be used and how deep the foundation layers need to be. The last thing that you want to happen is that you get any differential slump across the slab during pour. This can and has happened. My slab had to support an outer stone skin; Jeremy's didn't: we had to have internal load bearing cross members. The slab has to have a design than is demonstrably compliant to B Regs; it has to work both structurally and thermally.

Jan and I (or to be exact Jan) chose and put up some simple manual roller blinds on all of the bedrooms as a temporary measure a few weeks after we moved in. She used to have a fancy curtain sole-trader business for years so she's pretty expert at making posh curtains, blinds, etc. and intended to replace them at some point. However, the truth is that we both like the simple and clean lines, and they work well for bedrooms so we won't get around to replacing them anytime soon. What I misjudged is just how many little jobs need doing between the house being good enough to move into and being "finished" -- and we found the strain of getting to that point of moving in both mentally and physically exhausting. I would recommend to anyone just moving in that one of the first things to do is to have a bloody good break from it, go away on a holiday and both mentally and physically rest and recover. Then do an honest triage of the jobs still to do: those which you need to "properly" and get right first time; those where you can do a simple interim (like fitting roller blinds in our case) and come back to it in few years time if and when you have the energy, and those which quite honestly don't need doing at all for now and can wait until that "if and when" point. Moving in was a mountain that had to climbed again a ticking clock. You now have luxury of being able to change the tempo, and to prioritise and plan the finishing off tail minimising stress and taking the time to be able to enjoy the jobs more as a hobby.

You applied; he or she objected; you got permission; the house is now built, so it's a done deal. IMO, the issues are: Can you both move past the history of the objections? If so, then surely it would be good to move on, and only consider alternatives if this proves not to be the case. Does the neighbour understand the nuisance of the light? Perhaps a polite direct request explaining the issue might be the best first course. It might just work, and if it does then it would be a more amicable resolution. If you do raise a complaint then you should anticipate that it will become apparent that you are complainer since the spotlight is looking into your windows? I must admit that if I were reviewing the complaint, then I might be more receptive to the escalation if I knew that the originator had attempted to resolve this amicably, and the complaint was only an act of last recourse. I just feel that you will fair better if your actions are seen to be measured and proportionate.

@OnOff, this hindsight stuff is brilliant isn't it? It's a pity that the don't issue a Tardis as standard

Ian, to be totally honest, I only know because I said to our erection crew: "what are you doing that for?" Maybe it helped that I had teas and bacon butties in my hands at the time, but the crew boss decided to explain to the child in the room. I am being a little unfair -- they were bloody brilliant and always willing to explain. I think my BInsp was a bit stunned when he looked around the build. I can't remember the exact words, but his aside comment was very complementary about the build and sturdiness of the timber frame. In most interviews / reviews I used to get a pretty good instinct if the project / project was solid or you needed to dig deeper. I guess that in most cases the inspector are just the same: they get a good instinct as to whether the job is being done properly or not after the first few minutes looking around. With these guys it is just simpler to stay on the right side of them and avoid setting off any alarms -- even if unmerited.

For more details read and the 2,000 (bar 33 posts as of today) Clive, surely you were taking risks doing it this way and not putting support stand-offs to carry the rebar between the piping? You've got no way to stand in the room centre without pinching the pipe by the rebar under your weight. Even if you'd had temporary blocks and a standing board on top until you concreted, then you could have avoided this pinching.

I did a few in my old stone farmhouse back in the days when I was cash strapped. As everyone has said its not an easy job, and even though a ½m wall might look solid on the outside, you will be amazed at the crap that can fall out from the middle. The self-support angle runs at about 45° so if you try to remove the bit of wall to fit a 1.4m lintel then you could be faced with about 1.4 × 0.8 × 0.5 m³ of stone falling on you and a lot more if there is another opening above. OK, if the windows are small -- say 0.6m or less then it might just be case of making the hole with a single through centre acro support, banging in the lintels and making good, but not for a double window or door. At least with a ½m wall you may have a be able to use a double lintel which makes each hole more manageable, but you've still got to punch through for cross supports about the lintel line, open the lintel seat holes and prepare them, put in the back lintel and support, put in the front lintel and support both (I used 4 reinforced concrete lintels in one double doorway in an internal 0.6m wall), drop the centre and make up the quoins properly -- not just fill be holes with fixing coat as one builder that did a new window for me did -- and which I had to hack out and stone up properly a few years later to fix the damp problems. And this is times 3-6. Can this be done by a home DIYer with experience of stone work -- difficult but doable; by one who hasn't tacked this sort of job before and without advice from someone who has -- not recommended in my view. To be honest I am suspicious that the labour element is only £4K if you have a decent craftsman and his labourer and need to do granite stonework. Something is wrong here, IMO. I would ask to see examples of similar jobs that they've done, just to make sure that they know what they are tackling. Your job will also be complicated by the need to have the external finish sympathetic to the external structure and you will need to conform to BRegs and have Bcontrol approval, sign-off and inspection and possibly planning approval / certificate of lawful development as this is effecting the external facade of what I assume is an old building.

People sometimes make decisions that they wouldn't repeat with 20-20 hindsight ??. Our slab crew had done 100s of slabs the way that J, C and I showed without any issue. Rebar is heavy and the rebar ties are sharp. They finished tying down ours at about 4pm and the up-and-over concrete pourer was in action about 9am the following morning, if I recall correctly.

@recoveringacademic Ian, I've just posted separately on this. Sorry for missing your original post. My strong recommendation is to put them in now. Putting them in now as you place your joists is easy. Joist half way, slide them in; finish joisting and slide back into position then fix. If your BControl officer says that you need them and you haven't got them then you will have to be cutting holes through the ICF to slot them in from the outside. Uuaaaarrrhhh.

I see that Christine has her manifolds fitted before pour. Like @JSHarris they just cut off spare on the tails and tied them to a couple of bits of 2×4 which were tied to a couple of rebar verticals to hold them in the right position. We just taped over the ends and left them dry to avoid the risk of freezing. We only fitted the manifolds and pressure tested months later (about a year later, I think) once the internal were thoroughly dry and insulated as part of second fit.

Nope. and no your don't want to put it under the rebar. Our slab was build using exactly the same technique and there's a couple of similar pics on my blog. The rebar is all cut placed and tied. It is lifted onto the concrete block stand-offs pretty much last of all. If you zoom into the photo then you will see that they only bother with the minimal number of ties to keep the runs in position and straightish. Remember that in terms of the vertical tolerances this approach roughly centres the pipe in a 100mm slab so it doesn't need the same tight anchoring as an in-screed installation. The laying of the UFH is the last thing that they do before the pour. Adding the UFH was only about £2K extra in out build. An absolute bargain and a lot cheaper than in-screed versions.

The squeak occurs when one or more nails slip in the nail hole. The spiral ones and screws are far less likely to pull and slip. Joist spans over 2.5m need extra measures to prevent the tendency to twist when loaded. Staggered solid noggins are typically used for solid joists. In the case of PosiJoists extra lateral bearers. (I think our build two overlapped were 3×4s were slid in during erection for each long span to run the length of the room and then fixed in place before the floor was nailed in position.) Re the carpetting issue, we screwed down all of our boarding before the room were carpeted as an extra precaution to avoid squeak. The only one that we missed was one lateral to joist cross. Bugger again. It's any lateral runs that are a PITA as you have to be physically able to get the pipe in there. In a couple of cases we used straight - 45 - straight 45 - straight to form a nice roddable slow bend and one that I could get into position and still solder fit. We followed Nicks et all suggestion a radial HEP2O system with no hidden joints. HEP20 has enough forgiveness to pull through though it is really a two man job. Ditto the flexible radial MVHR systems.