This thirteenth entry was published originally by JSHarris on the 24th August 2013 and received 1,005 views on the closed forum
It seems that our luck is still following the path ordained by whichever environmentally protective deity I managed to offend a week or so ago with my quip about fracking, as now the drilling rig has broken down and had to be taken away for repair. This means no more borehole drilling for at least another ten days or more, something I’ll have to work around by re-planning the build schedule. It’s not really a problem for us, as we have no fixed target date for completion, but it does mean having to muck up the dates that I’ve arranged for various contractors and sub-contractors to be on site.
Anyway, the break gives me an opportunity to fill in some of the detail about the house we’re building, and how we approached some of the decisions we had to make.
When we first looked at the plot, in October 2011, we loved the location from the moment we saw it. Set at the junction of two very quiet single track lanes at the bottom of a valley, on the edge of an old Saxon village, with a millstream running alongside one lane, it was absolutely perfect in many ways. The plot faced south with no shading, this end of the village is very peaceful yet it’s within a 15 minute drive from either the city of Salisbury or the town of Shaftesbury, both of which have a wide range of amenities. The village has a shop and doctors surgery, but alas the pub that was still open when we agreed to buy the plot has since closed.
Before agreeing to buy the plot I did a lot of homework and research, and quickly found out that the costs associated with getting it level enough to build on and getting water and electricity in were going to be substantial. The plot had detailed planning permission for a rather nondescript three bedroom bungalow, whereas we wanted a two storey house, as we’re fed up with living on one floor. I asked a local valuer to value the finished house, as approved, to give us a feel for the gap between plot cost and finished value. The valuation came out at around £320k and the asking price for the plot was £125k. A bit of research revealed that we faced a bill of at least £25k to £30k to get services in, so I managed to get this knocked on the plot price. That left us with around £220k for the build, if we were to not spend more on the build than the final value.
My first set of costings showed that we were going to struggle to stay inside this budget, as we wanted to build to a pretty high airtightness and insulation level and also wanted to include some expensive technology, like a ground source heat pump, a large solar array and expensive Austrian made quadruple glazing. SWMBO also wanted features in the kitchen that were going to stretch the budget a fair bit!
As already mentioned earlier in this blog, we had a long delay between having our offer accepted and actually completing the purchase. This worked very much in our favour, as it gave us a long time to look long and hard at both the design of the house and the specification. I chose to design the house myself, as mentioned earlier, as I simply couldn’t find a local architectural practice that I felt either understood what we wanted or were prepared to listen and take heed of our firm requirements. The delay in purchasing the plot gave me time to learn a bit about architecture and design, to build several scale models to see how each design might look, and to learn how to mathematically model the thermal parameters of the house.
The latter caused us the greatest challenge, by far. We are conditioned into thinking that a comfortable house needs an excess of heating capability. Conventional central heating is always specified on the basis that it can provide far more heat than needed for 99% of the time, so that we are assured of comfort. However, when you design a house that has an extremely low heating requirement, even when it is really cold outside, all our preconceptions about heating have to, literally, be thrown out of the window. The problem is that this feels intuitively wrong. At every twist and turn of the design process I kept having to do a check on the heating requirements, and tended to want to err on the side of having far more heating capacity than we would ever need.
In the end I managed to take a lot of cost out by deciding that we didn’t need a ground source heat pump (the heating requirement was just too low to justify the very high cost) and we didn’t need heating upstairs. The latter point does have a fall back, as I’ve included electrical outlets for small wall mounted panel heaters to be added later, if we find we need them. Next we needed to get the build cost down, as all the builders I’d spoken to either didn’t understand how to meet our requirements for airtightness and insulation, or only offered a part of the solution, at a price that was way over our budget. At this stage I was still nervous about managing the whole build, so really wanted to find a builder that could at least give us a foundation system and house construction method that would complement each other, and who would take responsibility for the foundation and house shell construction. I also very much wanted to use a local builder, as I felt that it would be much easier to work with someone local, and morally it seemed far better to put money back into the local economy than spend it elsewhere.
After an enormous amount of chasing quotes from people (why, oh why are British builders so damned reluctant to quote or even reply to a request?) we concluded that we’d have to buy our house from outside the UK. To some extent the moral aspect of spending money overseas was offset by our chosen builder being Irish, and by the fact that I’m part Irish, so I can take pride in having a bit of Ireland as our home (my grandmother would certainly approve, if she were still alive!). We chose to buy our house from MBC Timberframe Ltd for several reasons. The first was that we had absolutely honest and clear details of the performance and construction methods they use from the start, unlike every other builder we approached. Best of all, they offered an integrated foundation system and house design and construction service, and the performance is to passive house standards, just what were after.
I sent them a set of drawings, and after a bit of negotiation we ended up striking a reasonable deal. The price for the insulated foundation system, slab, under floor heating and insulated, airtightness tested, shell worked out to a bit over £410/m² which seems pretty good for a house that meets passive house standards. We went over to Ireland for a couple of days to look at houses they had built, and take a look at the factory where the panels are made. We also went to look at an Irish window manufacturer, who make aluminium clad timber windows to passive house standards, even though we were set on using Internorm. We called in to the Munster Joinery showroom just outside Dublin, on our drive down to the factory in Cahir, Tipperary. To say we were impressed with the quality, performance and finish of the Munster Joinery windows and doors is an understatement. We’d previously been convinced that only the Austrian company Internorm could provide the quality and performance we were looking for, and had reconciled ourselves to paying the best part of £18k for the windows. Having seen the Munster Joinery windows and doors we asked them to quote. When they sent back the quote for their top spec triple glazed passive house product at just £8.5k (installed) I was truly gobsmacked.
The combination of buying the house from MBC Timberframe and the windows and doors from Munster Joinery will allow us to build our new home to the performance standards we want, without exceeding the cost of a more conventional, yet far lower performance, build. The icing on the cake (for me) is that I’ll feel a warm glow from living in a little bit of Ireland. SWMBO may feel differently, though, as her family still live in the same castle in the Marches they built around 1000 years ago, just after the Norman conquest, (one of the long line built to keep the Welsh at bay, although oddly enough she’s descended from Owain Glyndŵr, as there was a marriage of convenience between the Welsh and their English/Norman overlords back in the 15th century).
Éirinn go Brách!
ProDave 25 Aug 2013 08:18 PM :
As always great words of wisdom. You clearly have similar aims to our own. we want a very cheap to run comfortable home.
Perhaps the only area we differ, is our build is very cost sensitive (as it’s partly going to fund early retirement) so I would rather do things cheap, even if that means doing a lot of work myself, and therefore taking a long time.
I think I am perhaps lucky that I know, and have worked with a builder who understands and builds very well insulated eco homes, and I am hoping I can work with him to achieve our own project. In fact if it proves for some reason that I can’t work with him, then that will leave a big hole in our plans to be filled by someone else.
jsharris 26 Aug 2013 08:08 AM :
Our build is pretty cost sensitive, except that we were prepared to spend a lot on getting the plot ready to build because of the location. The actual house build cost (subtracting the high cost of levelling the plot and building the retaining wall) comes out at about £1200/m², including a 6.25kWp PV array in the roof (which is around £10k on its own).
For a house that meets the Passivhaus standard and has been built by me employing a main contractor for the foundation and frame and sub-contractors for the rest that seems a reasonable figure for this area (build costs here in the south are generally a fair bit more expensive than up where you are). The prices I had from local builders for a far poorer spec house were all around the £1300/m² mark.
SteamyTea 27 Aug 2013 08:19 AM :
Have you decided how you are going to integrate the PV into the roof yet?
jsharris 27 Aug 2013 12:18 PM :
Pretty much, although we’re still deciding between two fairly similar in-roof systems. The cheaper option is the Easy Roof system, with black-edged panels and black fastenings. The system I prefer is the Solar World Sundeck, but it looks as if it will be significantly more expensive plus I’m hearing noises from the supplier about long lead times on the components.
Both these systems are similar, in that they fit the panels on to an integrated mount/flashing system, so the panels act as the roof covering. The Solar World system has a complete tray under the panel, whereas the Easy Roof system just has a flashing system around the edge of each panel, rather like a Velux window kit.
The DNO have given a verbal OK for a G59 connection, so although this will mean taking a slightly lower FIT payment I can get away with only having a single phase, single inverter, connection (the alternative was to have 3.68 kWp on the higher FIT tariff on one phase plus the remaining panels on another phase on a lower tariff – we have three phase at the meter already).
SteamyTea 27 Aug 2013 10:23 PM :
I would be tempted to go for 2 G83 systems, you get some built in redundancy then. Does depend how much of your home grown you can burn though.
Is there much difference in the meter rental costs and would the DNO/Energy suppler fit a proper export meter or are they going to force you down the British Gas not so Smart meter.
That way you can undersize the larger inverter and get better low light performance.
I hope you are only going for SMA inverters. I think they have a new 3 kW one now, though you probably want to get a 3.5 and a 2.5 kW if going for reliability.
jsharris 28 Aug 2013 08:01 AM :
I did look at going down the two systems route, but there was a hefty cost implication, both from having a two phase connection (even though there’s a 3 phase cable 1m away from the meter they were still going to charge us a fair bit for the extra phase) and from having two inverters etc. I’ve already got a single phase connection and meter in now, as when the DNO said yes to a G59 connection there didn’t seem a lot of point in incurring the extra cost of bringing two phases in. The meter is a standard Siemens single phase one, not a smart meter.
SMA don’t seem to make a big single inverter AFAICS, the biggest Sunnyboy seems to be 5000 VA, and I didn’t really want to have two boxes on the wall if I could get away with just one. The inverter we’ve opted for is the Aurora PVI-6000.
Our predicted annual generation is a bit over 6500 kWh, which is enough to run our house with a bit left over, so we’ll be a net exporter overall (although we’ll be importing during the winter and exporting during the summer).
Shah 28 Aug 2013 12:33 PM :
Very good write up as always JSH. £1200/m² is quite a good price. How does it affect if the house is bigger (say 300m²+). Does it make it cheaper per m²?
jsharris 29 Aug 2013 07:35 AM :
Yes, generally costs come down per m² as the house gets larger. You can get a feel for how much this reduction is by comparing the prices in some of the self-build magazine build price tables (although I’d be wary of trusting their actual figures – my experience, and that of some others here, is that they are optimistic).
Shah 29 Aug 2013 11:04 AM :
Ah cool. Well I am just getting a feel of the expected costs but I guess the best way would be to breakdown all the separate stages and estimate the cost of materials as well as labour separately.
jsharris 29 Aug 2013 11:34 AM :
One thing I’m finding out is that the price of materials, particularly electrical fittings, is very variable. For example, I drew up an electrical spec, defining every socket, switch, data outlet, TV and telephone point etc in the house, produced a list of all the parts needed (including cable, cable clips, back boxes etc) and had it costed by the local electrical wholesaler. The price came back at over £2,700, more than Newey’s standard trade price and I thought Newey’s were pricey.
A half day of searching around the web found a couple of suppliers that offered far better pricing for the same brand name items. I ended up getting all the cable, switches, sockets, light fittings etc on line for ££1,179.08, saving over £1,500.
I’ve also found that you can get around 15% or more off everyday building stuff just by shopping around amongst local builders merchants – our local independent is consistently cheaper than the big name BMs.
ProDave 29 Aug 2013 07:44 PM :
For electrical accessories, I am a great fan of Click Mode.
Quite nice looking stuff, but at budget prices. Sadly not many wholesalers stock them, but easy to get on line.
Their light switches are nice as they are modular, you can swap the switch modules over, handy if an unusual lighting scheme calls for multi gang intermediate light switches for instance.
jsharris 29 Aug 2013 08:09 PM :
I’d not seen Click Mode, the prices look very good. We’ve opted for MK Logic Plus, a bit pricier than the Click Mode stuff, but with a fairly good reputation for reliability, I believe. The thing that swung us towards MK was their (rather expensive) 4 gang combination plate, with 4 13A outlets, a phone socket, two satellite F types and three VHF sockets, plus space for four Euro modules.
ProDave 29 Aug 2013 08:59 PM :
In the trade, MK now has a reputation for cheap imported stuff. Not a patch on what it used to be.
jsharris 30 Aug 2013 07:12 AM :
That’s interesting, as one reason we chose MK Logic Plus (apart from liking the nice solid feel of the switches and the smooth lines) was that they are supposedly made in the UK. I’ve just checked the sockets and switches that arrived yesterday and they are all clearly marked “made in the UK”, both on the items and the boxes. The quality seems very high for the price, not at all like the cheaper stuff like Emco or the no-name stuff the DIY sheds sell.
Shah 30 Aug 2013 10:26 AM :
4 gang combination is a massive socket!! one stop for everything . These days more and more stuff is made by China. Maybe it depends on the outlet you buy from… some will have made in UK stuff otherw won’t.
jsharris 30 Aug 2013 10:39 AM :
Yes, it is a big fitting, but the advantage of it is that it has enough power outlets to feed the TV, PVR, stereo and a DECT phone base, plus it has the two sat feeds that the PVR needs, a TV, FM and DAB aerial socket and a phone socket. I’m fitting four speaker connections into the spare Euro module spaces and sticking the speaker leads in the walls, with speaker outlets in the corners of the room. The result will be no trailing wires, which I think is worth the high cost of the unit (it’s this one: http://www.mkelectri…s/K2740WHI.aspx).
Shah 30 Aug 2013 11:44 AM :
Yes and it is cool. What is that empty Flush space for? I will add these sockets to information bank . Will help whenever I build/renovate. Not easy finding a plot! and I want a full acre for my dream house
jsharris 30 Aug 2013 02:11 PM :
The space accepts four Euro modules, to add additional switches or sockets. The Euro module system consists of standard size modules (25mm x 50mm) that click fit into a frame. There are some examples of them here: http://www.euronetwo…clip-in-modules
Using them you can add things like Ethernet, HDMI etc sockets to this plate.
Shah 30 Aug 2013 02:47 PM :
Niceee that is really good. That will make life so much easier. USB charger, HDMI, Ethernet and all the other stuff in one socket!!
wittenham 03 Sep 2013 12:54 PM :
JS, as you know, I am also going with MBC. The ‘no BS’ approach is what convinced me, along with the benefits you highlighted.
Now to get it built… when the foundations question is resolved, I will write a final post on the thread I started some time back.