Jeremy Harris

With hindsight, that would have been the perfect approach for us, too. I found that the layout and overall dimensions were pretty tightly constrained by the plot and the conditions imposed, mainly by the Environment Agency and the AONB design "guidance". What I struggled with a great deal was how to turn a featureless box that had all the right room sizes and locations into something that looked half decent. I don't have an artistic cell in my body, so I ended up looking at lots and lots of house photos on the internet, and then going through an iterative process with several scale models until we had something we both agreed looked OK. The hardest part for me was getting the detail and proportions of the external elements half-way right and this is something that I'm sure an architect would have been able to help with a great deal.

Yes, is the simple answer, at least in England and Wales (not sure about Scotland and NI). The Part G3 sign off should be easy, as it only relates to the pressurised cylinder and its control group, but the Part P bit might be harder, as usually the sign off is for the whole installation. You can separate this out, though. I did, in that I had our initial electrical installation (that was just the temporary site supply wiring and the treatment plant outlet) signed off as one installation, and then had the main installation signed off later, once the house was complete.

I can easily believe that the vast majority of architects simply couldn't make a profit from self-builds. Accepting that I had no architectural knowledge or experience at all, but did have the slight advantage of around 25 years experience of using CAD, and was familiar with producing technical drawings, I would guess that I put well over 1000 hours into the design of our house, and went through several iterations, over the course of a design process that took around a year. On top of that, I must have put a similar amount of time into reading up on architecture and design, reading and gaining an understanding of building regulations, as they applied to design and layout, and reading up on all the conditions imposed by being adjacent to a listed building and inside an AONB. For an architect to have done a half-decent job of the design alone, ignoring any additional services, such as looking after the planning application, doing the building regs application or overseeing and providing a management service for the build itself, would have meant that they would have been working for a pretty low hourly rate, I'm sure.

@Ian, I second @jack's comments, but would add that I think there is a problem that is specific to self-builders, in that it can be pretty tough for self-builders to find an architect they can work with. @jack has explained his difficulties. Our experience was a bit different, in that I hawked our outline requirements around four local architectural practices and had four very unhelpful responses, to the extent that we both felt very demoralised about the whole idea of self-build, and wondered if we'd be better off forgetting about it, and buying a renovation project. Admittedly, we were experiencing a long delay in buying our plot at the time, and that added to our general feeling of disillusion. As said before here, I ended up designing our house myself, not because I wanted to, but really because I had no choice. We did talk to an architectural technician, and we would have been very happy to work with him, but he was planning to retire, and was reluctant to take on our project. I found the process of doing a crash course in learning about house design in a year bloody tough, and a great deal of hard work. I have always felt that our house would have been better with an architect's input, and since we've built it I've met a local architect who I would have been very happy to work with, and who I've recommended to a few people. I think a lot of the hassle self-builders often seem to have with architects may come down to self-builders often having very strong views about what they want, and some architects also having strong views as to what they think their clients should want. This seems to be a theme that not only crops up here from time to time, but also on TV programmes. The most memorable example I can recall is the Grand Designs episode where the clients (Welsh soap opera actors, IIRC) and their architect fell out to the point where they only communicated by letter, but there have been several instances in these shows where there has been a lot of conflict between clients and architects. I'm not at all sure why this should be, and would be interested in understanding why this happens so often.

Those were thoughts that certainly heavily influenced our decision to try and build a "no bills, no physical work required" house. On your last point, this is my very first ever post on this forum's predecessor, ebuild: http://www.ebuild.co.uk/topic/6386-earth-sheltered-house-any-pp-tips/#entry22585

You can do what you want, within reason, but even if you just do the very bare minimum to comply with Part L1a you will end up with a reasonably well insulated house. Not great, but certainly well into the region where you my well find that a wood burning stove puts out far too much heat for an average sized room a fair bit of the time, so won't get used as much as you might think. There's no doubt that a well-ventilated house (specifically with MVHR, as ventilation rates from these will, in practice, be lot higher) will dry things much faster. It's one of the most noticeable things from fitting MVHR, second to the noticeably better air quality, that things like damp towels just dry a great deal faster with MVHR. One conundrum with any combustion stove and even building regs airtightness levels is that you're pretty much pushed towards having a room sealed stove, which does little to improve ventilations rates. Finally, there is your health, and that of your neighbours, to consider. The particulates and other toxic emissions from burning wood are massively greater than from other well-known air pollution sources. In very rough terms, a conventional wood burning stove is around 100 times more harmful than a diesel car, so you can roughly equate having one running to having around 100 diesel cars parked outside with their engines running. Ultimately, it's your choice, but my guess is that we will see increased legislation against burning wood and coal before long, plus you may well find that, even if you build to the very worst energy performance standard that will still scrape through Part L1a you will still be stuck in a situation where a wood burner puts out far too much heat a lot of the time when you want heating, which then leads you towards having two heating systems, one that can be run when modest levels of heat are required, and the wood burner for days when the weather is very cold.

Ours too. I can't imagine what it would have been like without the weekly clean and pump out. Even then, the hand washing water tank would often run out between weekly services, and I'd have to fill it back up with 25 litre containers ferried 16 miles from our old house, as we had no water on site.

The recurring theme of obvious non-compliance with building regs on Grand Designs needs to be addressed, I think, especially as we seem to regularly get breaches that aren't just minor stuff, but really significant safety-related issues, like staircases without rails or any protection from falling. I understand that the programme is primarily about the aesthetics of design, and so they take the view that the look is more important than the function is some cases, but they are creating an expectation with some viewers that it's perfectly OK to have potentially dangerous features, as long as they match the aesthetic of the building. In terms of heating demand, last nights house was pretty much the same as ours. We had minor over heating at first, caused primarily because we created a very sheltered spot by digging back into a South-facing slope, which increases the outside air temperature a couple of degrees above that we used to model the thermal performance. I learned pretty quickly that a well-insulated house is far more susceptible to relatively small changes in incidental heat gain, including solar gain, than I'd anticipated. Nothing that couldn't be managed, but I fell into the trap of worrying far more about the heating system, rather spring and autumn overheating (spring and autumn are by far the worst times, because of the lower sun angle and deeper penetration into the house, we've found).

There will also be a problem with airtightness with an electronic lock, as the door will need multipoint latches to pull it tight to the seals all around. I've not seen an electronically activated latch that includes actuators for latching the door at several locations and pulling it tight to the seals, but there are some commercial electronically operated handles that will allow a standard multipoint latch rail to be fitted, so the handle can be pulled up to close the door tight to the seals, then electronically latched. An alternative might be to have an external to the heated envelope draught lobby, with a normal multipoint latch airtight inner door, plus the feature front door, that doesn't then need to be super airtight. I had a look at electronic locks both a couple of years ago, and just a week or so ago, as I would like to change our front door lock to one that doesn't need a key. As @PeterW says, electronic strike plates are out as far as insurers go, plus there is no normal strike plate, as such, on a modern multipoint latch door mechanism for an airtight door, but there are a couple of electronic locks (not latch plates) that might meet the requirements of an insurer. The problem I ran into was that they can't be retrofitted to an existing door, as they are designed to work with a small range of spacings between the outer face of the door and the multipoint latch rail that runs up the whole height of the opening side of the door. These latch rails are set at the centre point of a Euro lock barrel, or similar, and and has to be set into the door frame between the outer weather seal and the inner airtightness seal. It may be that for a custom door you could arrange for the design to have the rail at the right place for the limited range these locks cover, but they are pricey. It's probably worth having a good look at how passive house standard doors and seals work, then having a think about how you could sketch up something that a good joiner could build. Some of the clever stuff is hidden, like the measures taken inside the frame to provide a thermal break between the inner and outer frame faces, as most of the heat loss in a decent door or window is through the frame, rather than the glazing. For example, some passive doors use foam between the inner and outer frames, some use cork, but there will always have to be something to reduce the thermal bridge through the frame, and getting the detail of this right, whilst providing a structural fixing point for the latch rail up the whole length of the door opening face, needs some careful design work.

I agree. The chap that did our drive work and all the hard landscaping was VAT registered when we first started to use him, but decided that, as he was now doing smaller jobs on his own most of the time he would de-register. I had him back to lay some paths and build a couple of bit of stuff from stone and he was struggling to stay under the VAT threshold, as a lot of his work was now smaller garden-type jobs where he was buying the materials. He was quite grateful when I offered to buy the materials for the job, as it would reduce his turnover a bit and help keep him under the VAT threshold. His reasons for de-registering were mainly to do with reducing his labour rate by 20%, to be more competitive with all the other non-VAT registered people locally doing similar work, but his view was that it was near-impossible to stay under the VAT threshold doing hard landscaping work, just because more than half his costs were materials. Self-builders may be happy to pay up front for the materials and claim the VAT back, but very few other people are, it seems. He reckoned that the only way most of the non-VAT registered people could get away with it was by doing a fair bit of "cash in hand" work and being creative with their tax and materials invoices..............

Your electrician will have a loop impedance tester, probably built in to a multi test machine, and the measured value of Ze will have to be recorded with the paperwork.

Thanks, that's a neat idea, especially as it gives a lot more capacity that the original, will have a very long storage life and is cheaper!

Many years ago, washing up liquid used to be commonly used to make mortar "wet" a bit better and to make it more workable. It was found that it tends to make the mortar weaker, especially if a bit too much was used, and especially if mixed for a long time, where the foaming tended to cause far too many air bubbles (some air bubbles are what makes the mortar more workable). As a consequence, it's not recommended now, and admix was formulated to do the same job, but without the problems that some detergents can cause, especially those that use salt as a thickening agent. FWIW, when I was a small boy, being taught how to lay bricks, the very good bricklayer that was teaching me always used a squirt of washing up liquid in the mix, but that was in the mid sixties, before admix was around. People have been parge coating walls with a wash of strong cement mix and a brush or roller for decades without problems, so frankly I think you're over-thinking this. This is just an airtightness layer you're applying, isn't it, not the base for a proper render system?

I've fitted a doppler radar detector part way up our drive to trigger the CCTV to record. Cheap and easy, but needs power. Needless to say mine's home made, but it's based on a cheap microwave motion sensor module that switches power to a 433 MHz wireless transmitter, that has a pretty long range (I tested it and it works out to around 100m +). There are almost certainly commercial units that use the same sort of technology. The microwave doppler units are immune from false triggering from day time warm air gusts (something that plagued the PIR sensor I initially tried to use) and some have an adjustable sensitivity, so you can set the size of object, and range, that will cause them to trigger.

Probably - the 15V battery for the AVO definitely should be, as they aren't that easy to buy any more.

I still have a wind-up Megger and an Avo 8.......................

I've tried three different types, the pads that fit into work trousers, the hard faced pads with straps and my old commercial divers neoprene ones that I used to use when caving. All have drawbacks. If you're on your knees a lot, without getting up much, then the hard faced pads are OK, but if you walk around with them a lot they tend to rotate around and be a nuisance. They are quick to put on and take off, though. I tried both the conventional strap method, with the top and bottom straps going around the back of your leg, and the "miners" strap method, where you cross the straps over at the back. The latter makes walking easier, but also tends to make the pads move around a lot more. The trouser knee pads are fine for jobs where you're getting up and down a lot, but they aren't that comfortable to walk around in, plus the knee pad foam seems to compress and get a bit thin after a fair bit of use. Overall the commercial divers knee pads were probably the best compromise, their main draw backs were a tendency to make the back of you legs a bit sore and poorer resistance to penetration from sharp objects on the floor. They are also a pain to get on and off, as they are intended to be slid over the outside of a wetsuit, so have no fasteners. Overall I don't have a favourite for all jobs. When laying flooring I used the trouser pads most of the time, as there was a lot of getting up and down, cutting the flooring to size. When sealing some OSB flooring in our eaves storage areas yesterday (ready to stick carpet tiles down) I used the hard knee pads, as I was on my knees pretty much the whole time, but not for very long, and they were quick to get on and off.

Hydrated lime takes for ever and a day to cure, as it cures by carbonation from CO2 in the air. Both end up the same eventually. If you really think that you need more flexibility in your parge coat (and I'm far from convinced that you do, given that the base blocks are cementitious, anyway, plus the fibres will tend to resist cracking), then using a lime based mix will increase flexibility, but will tend to delay the cure a bit. Something like a mix of 1 part NHL 3.5 (Natural Hydraulic Lime), 2 parts fine sand, will work much the same as your previous cement mix, and give a reasonable cure time, but frankly I'm not convinced it's worth the additional cost and hassle. Be aware that you need protective gear with this - the lime can cause skin burns.

Make sure it's hydraulic lime, not hydrated lime..

And it's easier and more practical to do, too, especially with a nice high wattage bulb so you get a decent earth current. The snag is that you don't have an exact number to enter into some form to show that the impedance is low enough, not that knowing the exact impedance makes it any safer, it just keeps the paperwork police happy.............

Hydraulic lime is added to cement render to help prevent cracking, but not normally to a parge coat like this, AFAIK. Our sand and cement rendered wall has has hydraulic lime added for just this reason, but that's much thicker, and was applied in two layers, a rough base layer on the blockwork then the finish layer.

As above, I was happy to pay a £10k deposit on a £60k contract, so 12% 16.7%. This seemed fair and reasonable to me, as the last thing I wanted was for the builder to have cash flow problems.

My workshop arrangement was done primarily because I have machine tools in there, a lathe, two milling machines, a bandsaw, mitre saw and pillar drill, plus a half-built CNC router. This kit all has lots of exposed metal, so I was keen that it be as close to the potential of the floor as possible, in the event of a fault. This is really belt and braces stuff, as the incomer to the workshop is a 40 A DP, 30 mA trip, RCBO, so any imbalance in current between line and neutral, as might be created by earth leakage from a fault, will turn the power off, anyway. It can be surprisingly difficult to get a low earth impedance with an earth rod, and it's a PITA to assess the true earth resistivity (there's a method here, which is the one I used: http://www.wiley.com/legacy/wileychi/eca_wiringregulations/supp/Appendix_12.pdf ). Our soil is pretty wet clay, which is about as good as it gets, but to get a really low impedance I ended up driving two 4ft rods into the clay under the workshop slab. To make the installation neat and well-protected, the workshop earth rod goes down through the inside corner of the floor slab and is terminated inside a boxed in area, so is well protected from damage. For some soil types a rod may not be OK, and you may need to bury a grid or mat.

I was more than happy to agree a stage payment plan that went like this, on a contract that was just over £60k: 1. £10,000 deposit to cover the cost of detailed design and materials for the frame, payable with order. 2. £13,000 second stage payment to be paid two weeks before start of foundation works, to cover cost of materials for foundations. 3. £20,000 to be paid on delivery of the house and garage frame kit to the site. 4. £7,409 to be paid on completion of frame erection and membrane and battening of the roof to be rain proof. 5. £10,000 to be paid after internal boarding out and insulation pumped in, subject to the air permeability test result being equal to, or less than, the PassivHaus standard of 0.6 ACH at 50 Pa. Bear in mind that work started on the foundations on the Monday of week one, and was completed by Thursday the same week. Work started on the erection of the house frame on Tuesday of week two and was completed by midday on Saturday, so this was a very quick build.

Doesn't matter. Any diversion device will just modulate the power down to a few watts, as required to keep the system from importing. Some can run two 3 kW immersions, if need be. Mine can switch up to 20 A OK, so would be OK with a 5 kW immersion, if such a thing was available. If the excess PV was only 100 W that's all that would be sent to the immersion. There's no need for a small immersion, unless you intend doing something like running an off-grid system with a low level background generation capability (something like a small hydro plant that delivers a fairly constant low power).