Jeremy Harris

We sourced our larch cladding very locally, as in grown 6 miles away at Fonthill Estate, milled 3 miles away at Ansty Sawmill and delivered on a trailer behind a Landrover. In the main it's not moved much, and is changing colour gradually from an almost orange/red when first put up to a silvery grey. The East elevation is more grey than the South or West and the North is still looking quite red. We get a lot of algae on the shaded path along the North side which indicates to me that it's probably always cool and damp there. There's no sign of any black staining anywhere, even on this fairly damp North side. I did design the house with larger than normal eaves and verge overhang and they are very effective at keeping a lot of the rain off - the top few feet of the walls never ever get wet, even in the heavy driving rain we've had earlier this week. The North side in particular is well sheltered by having the high retaining wall only about 1.5m away from it, too. The worst elevation for movement is the West, and this faces the prevailing wind and rain and I suspect gets a fair bit wetter than the other three sides. The East elevation gets the most sun, which seems odd, but I think it's because the morning sun is powerful and by midday on a hot day there is often cloud or haze to reduce the impact of the sun. By the same token it's the East facing windows that have the most solar gain. Our larch is wide board waney edge, with boards typically between 200 and 350mm wide and 20mm thick. The only place there's slight cupping is on one board on the West elevation, where I've had to add some screws to hold it back down. It's a rustic finish, designed to look like many of the old local timber barns, but the cladding was cheap as chips, £9.90/m² inc VAT, £8.25/m² ex VAT. It was around £2,150 ex VAT for all the cladding for the house and garage. The labour to fit it was more costly than the timber.......................

Thanks Ian, that will make it easier to find, I'm sure. I remember looking all over the place for it in Ebuild whenever someone asked about it!

Ages ago I wrote a spreadsheet for doing what-if comparisons to see whether it was better to invest in more insulation in the walls, roof, floor, fit better windows and doors, or fit a better MVHR system. Others have found it useful and I've been reminded that I've not re-posted it over here, so here's the latest version. It should be self-explanatory, you fill in the cells with your wall, roof/ceiling and floor areas, add the areas of each door and window, put in the U values for each and, if you can, get hold of the met data from the met office for your area (the data in there is for West Wiltshire, right on the border with Dorset). This isn't a thorough modelling tool, it just looks at heat loss fairly accurately but doesn't take into account heat gains, although there is a crude way of doing that by drawing a line across the seasonal plot at the point where you don't use heating and you can very roughly assume that anything above that line will be heating. Please feel free to ask any questions, but bear in mind I wrote it back when I was designing our house and haven't used it for a couple of years. so I may be a bit rusty. Heat loss calculator - Master.xls [edited to add latest version of the spreadsheet]

Ours was shipped from a warehouse in Denmark, at the supplier. So it travelled from the Danish manufacturer to the Danish suppliers warehouse and was then shipped on a special delivery pallet to the UK, all for less than half the cost of the UK suppliers shipping charge. Assuming the UK supplier just drop ships from the Danish factory, then I'd have expected a delivery charge the same as, or slightly less than, the special delivery pallet delivery we had from the Danish supplier. As mentioned before, I don't think that Denmark is a particularly cheap place to do business, as they have relatively high taxation and living costs.

Quick question for Nick. Is it OK to use Karndean of Amtico over UFH? I've just been asked the question and thought you'd be the one person here to know for sure.

That's a damned good price. Our place is probably smaller and I paid £1200, labour only, for three coats everywhere, in five different colours, done conventionally with a roller.

Bear in mind that there will always be a significant "breeze" blowing in and out of the MVHR terminals, roughly half the volume of your whole house every hour, through a 150 to 160mm diameter hole. That tends to over-ride the near-ground level static air, in my experience.

The air temperature tends to be the same all around the house, as it's usually always moving to some degree, even on a "windless" day. The sun doesn't really directly warm air very much, it warms surfaces that then warm air, but the flow rates through the MVHR terminals is high enough for there to be very little heating effect, I think. Our intake is on the North wall, under the eaves, and last week it was drawing in air at 29 deg C.

I think I'd be inclined to put them up through the roof. Almost certainly the easiest option and probably means fewer bends, too. It doesn't matter then if they are on the windward or leeward side, as they'll be at 90 deg to the wind anyway.

Thanks guys, I'll give it a go. Probably not immediately because it's about 4m up a vaulted ceiling and is a bit of a pain to get to.......... Sorry for de-railing the thread.

Tell me about it................ I went around filling cracks and a handful of plasterboard screw pops and re-painting about 6 months after the house was painted. I probably have a dozen or so cracks that have opened up again, plus another handful of plasterboard screw pops. I've just put light pencil marks by them for now, so I can tell when new ones have stopped appearing. I'm pretty sure the vast majority of cracks stopped showing after around 18 months, but have wondered if we'd have been better off leaving off doing the painting until a lot later, even though that would have meant more masking up and cutting in. BTW, amongst all this talk of fillers (and I've been using that Screwfix stuff Nick linked to, on the recommendation of our decorator) does anyone know of a really good flexible filler? We have a very fine crack, just a hairline one, that is very noticeable because of where it is (the hall vaulted ceiling) and I've repaired it twice now. The second time I sanded down through the plaster skim to check there was scrim tape in place (there was) and to add additional screws, then I filled and sanded the whole area back flat again and painted it with three coats, with a big overlap to hide the repaired area. The very fine hairline crack's appeared again, presumably because there's very slight natural movement with expansion and contraction in that area. I've been wondering if a flexible filler might stop this hairline crack from coming back.

OK, I've pretty much sorted everything out now, to get a neater looking internal unit and to comply with electrical safety regs. The internal unit is the slightly more complex one to put together, so the only legal way I can supply it is with a plug in isolated DC supply. This sidesteps the need for me to comply with the LV Directive and get it approved and CE marked, and by using an approved 433MHz LPD transceiver I sidestep the need for approval with the EMC Directive, as the power consumption of the display circuit is so tiny that there is no risk of any EMC emissions problem with other kit, and it shouldn't be susceptible to interference anyway (by design). It's not a safety critical item so even if it there ever is a susceptibility issue (extremely unlikely) then it doesn't matter as it can't cause a hazard (don't you just love EU rules?). I've sourced some neat and robust double insulated 5V plug in power supplies, with a UK plug and a valid CE mark, and also sourced a wall-mounted case that has a moulded in display window for a larger display. The new display has large characters that are black on a very gently white back lit screen. It can display a single line of 16 characters, so can have more meaningful messages than the smaller 8 character display on the prototype. In my view, the outdoor unit is unsuitable for operation from a plug in power supply, as few, if any, will fit inside an IP protected socket with the lid closed and locked. So, the outdoor unit will look almost identical to the one in the grey box on the previous page in this thread, but with a slight change to the circuit board to improve the layout and make it easier to build. I've built one to the new layout and tested it and it works fine. Because the outdoor unit has an integral power supply, it would be illegal for me to sell or give away, without approval against the LV Directive and the appropriate CE marking. As this would cost thousands, it's clearly impractical for me to do. So, to sidestep this what I'm planning to do is supply the outdoor unit as a partly assembled kit, so each of you becomes the "manufacturer" in effect. This is fine, as it's perfectly OK (within the EU regs) for someone to build their own electrical kit. I think I can get away with providing the outdoor unit as an assembled and tested circuit board, with the mains lead already attached (it'll be a length of black 3 core 0.75mm² HO5RN outdoor cable - please let me know if you want more than 2 metres of cable). All that will be needed to assemble the unit will be for the cable(s) to be fed through the cable glands fitted to the grey IP65 box, the circuit board screwed down to the captive threaded holes in the box, the air pipe connection (and level switch connection, if needed) made, the lid fitted (after securing the unit vertically to something with screws through the mounting holes) and you will need to supply and fit a standard 13A plug with a 3A fuse, or wire the cable to a suitable switched and 3A fused outlet. The outside unit will have a hose barb fitting in the base, next to the cable glands, to take the air pressure sense pipe. This fitting will be threaded into the case and will already have a short length of 2.5mm bore PU hose to connect internally to the pressure sensor on the PCB (it's a tight push fit). On the outside, this hose barb takes a 4mm ID hose, again a push fit, so you will need to make sure that there is provision to connect this to your air feed to the treatment plant. My unit has an unequal plastic tee fitted right next to the pump with 19mm through port and a 4mm ID (6mm OD) push fit barbed hose fitting on the side. If anyone needs something making up I can quickly make up a tee to fit whatever air pipe size you need from acetal. I'm hoping to get some time this weekend to finish the first one or two, so should have some photos. I'm going to try and see what the range is like with an internal antenna on the indoor unit, really just because it will look a bit neater, so will wait to take photos until I'm sure of the appearance.

Your conditions are probably atypical for many other parts of the UK (exposed, near-constant wind etc) but you do get very long days in summer, so I think I'd look long and hard at the decrement delay. It may well be worth making a compromise on U value to get a longer decrement delay, in terms of comfort level during any long sunny days you might get up there.

Yes, with a big house the impact of improving the insulation level decreases quite markedly. By the time you get to the likes of a DIY shed supermarket it's barely worth having more than a thin layer of insulation, because of the change in surface area to volume ratio. For big houses it's ventilation heat loss that is very dominant, so good airtightness and a high performance MVHR will reap a greater benefit than improving the wall, floor and roof insulation. Our idea was to downsize with the new house, but at 2 bedrooms and 130m² habitable floor space it's 44% bigger than the three bed bungalow we're in at the moment!

I found that "proving" a trade qualification as an "electrician" was easy with Screwfix. They say they need evidence of membership of ELECSA, NAPIT or whatever, but they accepted my 35 year old City and Guilds 15th Ed ticket without question!

CfSH was a joke. It wasn't really focussed on energy conservation, but ended up being taken over by a whole raft of requirements that were of no benefit whatsoever in a large number of cases. Take our area, as an example. We would have got CfSH points for bicycle storage. Great idea, except the hill beside our house is about 1 in 5 and even though I cycle regularly there's no way I can tackle it on a bike. It was very largely a box-ticking exercise, too, as to get a given level you have to gain a certain number of points, and compliance with, or exceeding, the requirements of Part L1A wasn't a major part of the points total. As a starting point, I'd like to see a return to 100% inspections, with no way that the developer can buy off the inspectors, as they can at the moment. That was one partially good thing about CfSH, in that it did demand 100% inspection to reach the higher levels, so someone in government must have known, or suspected, that developers and big housing estate builders were cheating (mind you that seems to have been common knowledge for some time, this is worth a read if you not already read it: http://www.aecb.net/publications/we-must-change-our-disgraceful-approach-to-build-quality-or-wave-goodbye-to-energy-savings/ ).

It's barking mad! In England and Wales, the EA much PREFER that you drain a treatment plant to a watercourse that runs all year around, and consider land drains and soakaways to be a less preferred option. In Scotland SEPA take the opposite approach. Given that both bodies have essentially the same responsibilities, you have to wonder quite what the rationale is behind their decision making processes.

As above, I found Nu-Heat incompetent and Wunda very good. FWIW, the Wunda manifold, thermostatic valve and pump set that I bought happens to work very well for a low temperature UFH system, so if you're only looking for a low heat output, the thermostatic valve supplied with the Wunda pump set (this one: http://www.wundatrade.co.uk/manifolds-pump-stations/401-standard-pumpset-grundfos-eup-pump.html ) works OK down to about 24 deg C flow temperature. I tried to get a three port TMV on another system to work at a low temperature and even removing the stop found that it wouldn't regulate below about 28 deg C. This may be significant if, like us, you're using a low temperature slab approach. I can also verify that this pump set and thermostatic valve has no problem when pumping cold water through it to cool the floor, if anyone is thinking of floor cooling for solar gain reduction.

We're on clay and as Ferdinand says, I fitted a large underground surge run-off tank. This drains from one corner to a thin layer of permeable soil, which I know for sure just drains under the lane into the stream. We were forbidden from draining rain water run-off into the stream, but immediately given a licence to discharge sewage effluent to the same stream (yes, you too can scratch your head in puzzlement at the workings of the Environment Agency, who control both these aspects, from different offices). When digging the services trench around our plot we uncovered an old clay land drain pipe running down the side of the lane, then under it at the bottom and discharging into the stream. It had been put in to take the run off water from the steep lane alongside our plot, and as it was unjointed clay pipe my guess is that it was probably Victorian. What I eventually found was that the building inspector was OK with the principle that Ferdinand has mentioned - that the development won't change the flood response time. Our surge storage actually means we've slowed the run-off time, as our site was a clay slope that allowed water to run off freely, cross the lane and flow into the stream. Now it all collects in the tank and runs off unseen underground.

The Wickes one works well, and well worth checking Wickes against their parent company, Travis Perkins, as most of the time using Wickes with 10% discount is cheaper than TP with a trade account, often by 10 to 20% (don't ask me why this is - I've had the debate with TP, where I have an account, and they don't know...............). Also, if you're over 60, then B&Q give a 10% discount on Wednesdays, you just have to apply for a Diamond Club card.

I've no problem with any disagreement, this was just a very simplistic model. Everything you say is right, and it's unlikely that anyone would use a full price direct electric tariff for heating, but the saving proportion is the same whatever fuel is used - I just picked a number (15p per kWh including standing charges) that illustrated a price difference. One odd thing is that when I've looked at the cheaper tariffs for the sort of electricity consumption our 130m² home would have (without the solar panels) they have (so far) all turned out to cost more than this per unit when the standing charge is taken into account. All I was trying to do here was illustrate one point, very simplistically, as an illustration, not a practical home. There are dozens of compromises that will impact on a real house, but it was this single principle of the non-linearity of heating cost as you reduce the heating requirement that I was trying to illustrate, as that seems to be something that some don't always take account of, as I mentioned in the first two paragraphs. Not everyone here is building a new house, either, some here are renovating, converting or restoring, and I'm not sure that many here are building houses of 150m² or more, even if that is the average for new self-builds. I may be wrong, but I get the impression that there are a lot of us are building in the 100 to 150m² range and some smaller than that, with only a few that are bigger. I'd also guess that the more cost-constrained are going to be building at the lower end of the size range and may well reap greater benefits (in proportion to their income) from having significant lower energy bills, or no energy bills at all, which really isn't either costly or difficult to achieve, we've found. Our total build costs, including the solar panels and MVHR, oak joinery throughout, fairly high to mid range kitchen and bathrooms and passive house levels of insulation and airtightness have come to about £1380/m². If we'd cut out the oak, travertine flooring, gone for budget kitchen and bathroom components, then that could easily have come down to £1200/m². Using an architect/project manager and budget to mid range kitchens and bathrooms would probably have ended up at around £1350/m². The average self-build cost for our part of the UK for this size of house is probably around £1400/m², for someone, like me, who uses a main contractor for all the ground works and another main contractor for the wind and weather tight shell, with sub-contractors for windows, roofing, electrics, plastering etc. Bigger houses may well be a bit cheaper, but then bigger houses don't need as high an insulation level, either, because of the better volume to surface area ratio. I'd be the first to say that any self build is a stack of compromises, driven by planning, the site, personal wishes, cost, etc, so there will be very wide variations. However, one consistent factor is that it is damned hard and costly to improve insulation levels once a house is built. After the house is built and been in use for a few years, and you, or the next owner, is in a financially better place, you can always change the windows and doors for better ones, fit a better heat recovery system, upgrade the kitchen and bathrooms, install solar panels, lay better flooring. So, if you're looking at making compromises it seems far better to not compromise on wall, floor and roof insulation, just because these can prove to be hard to improve later, and because, in the overall cost of even a budget build, insulation is only a small part of the cost.

The problem is that it's easy to show that a house isn't a PassivHaus, as it won't have a certificate from the PHI, but it's extremely challenging to prove that an ordinary new house doesn't comply with Part L1A of the building regs. Some builders have been caught out, when very persistent new owners have spent a lot of money getting intrusive surveys and thermal imaging done to show the absence of insulation, poor detailing around doors and windows etc, but there have only been a handful of cases, out of thousands of sub-standard homes across the country. The majority of new home owners won't have a clue that their houses have missing insulation etc, they'll just pay the energy bills and not for a moment wonder why their supposedly low energy home is costing so much to heat. You can't really blame them, as there's nothing on the energy performance certificate they get that really tells them in plain English what the heating cost should be. It's only when you get companies really taking the mickey, like leaving out all the insulation (and it has happened!) that owners start to notice that something might not be right, but even then they face an uphill struggle to prove their case, as there is no enforcement body and it's up to each owner to pursue the builders through the courts. That's and expensive and time consuming activity, and I doubt there are many owners with the commitment and deep enough pockets to try it.

You're right, enforcement is non-existent. Building control bodies that question anything on big developments don't get the next contract from that developer, so they don't make waves. LABC rarely do work for big developers, as I understand it. Even my BCO told me that he thought around 60% of new builds failed to comply with the regs, but there wasn't anything they could do about it, as they had no powers to enforce regs on any development where building control had been contracted to another provider.

I keep meaning to do some pictures to try and explain this better, as I know some find the numbers a challenge. There are some interesting consequences resulting from improving insulation/reducing heat loss, by only a modest amount. Having visitors around very quickly warms the whole house up, for example, as a couple of adults added to the occupancy can easily just reduce the need for any heating, even in cool weather, to zero. Similarly, the house becomes more sensitive to incidental gains, so the added heat from a bit of sun shining though a window can easily give more heat than is wanted, even in winter.

That wouldn't surprise me in the least. If I was extremely cynical (in the light of comments made by Russian officials apparently supporting the actions of their "Ultras" against English supporters) I might take a view that Russia sees the UK leaving the EU as a significant benefit, in terms of weakening it and so giving them a tighter grip on countries with EU leanings, like the Ukraine...............................