Jeremy Harris

In my case, the only "vent" hole in the cistern before the mod was the gap around where the cable slot was. After the mod there's a 1 1/2" pipe fitted to the side with a very low suction on it. At a guess, there's probably the capacity for at least an order of magnitude better air flow into the top of the cistern now than there was before. A conventional, non-built in, cistern, can have a fairly tightly fitting lid, in which case the only ventilation is via the overflow pipe, which is around 18mm bore. Anyway, I did this a couple of years ago, and both cisterns flush just as well as they did before the mod, so it doesn't seem to have any impact at all on flushing, and a test is always better than a bit of theory!

Nick, the suction pressure from the MVHR is very low and has no practical effect at all on the flush. Water being 1000 times denser than air means that you'd need a lot of suction to stop it flushing, probably half way to a vacuum..............

I used 3 core 2.5mm² flex, inside armoured flex conduit. Our heat pump had punch outs to accept an armoured conduit glands, and I ran the conduit through the wall (foamed in place and sealed) and then the cable ran directly into the back of a 45mm single back box with a single gang, DP switch on the wall of the utility room, right behind where the heat pump is outside. I also ran another armoured duct though the wall alongside, to take the low voltage control cable, that also terminates via a gland at the heat pump. 2.5mm² T&E runs from the DP switch up to the RCBO in the CU on the floor above (our CU is an all-RCBO one, I can't be done with the daft idea of 17th Ed split boxes, it makes far more sense to me to have an RCBO on every circuit).

Yes, I did get a good deal, but to be fair, the young electrician was a bit daunted by the job at first, or at least probably a bit daunted by the fact that I'd used to teach electricians (albeit, back than, all electricians that were employed by what was then the South West Electricity Board!). To be fair, we romped through the job, as I did a little bit more than labouring, just enough that he could be sure that the installation, securing of cables etc, was all up to his standards, rather than mine. I also did all the heavy stuff, like pull the 25mm 3 core SWA incomer through the duct and up to the first floor services room, and laid all the other external SWA runs, together with all the SWA cable glands (using those Gorilla nuts - at least they make that unpleasant task a bit easier). He terminated all the cables, fitted most of the back boxes (to noggins I'd already fitted) so there was a fairly even split of work. In my case, even though I'd have no problem showing that I was a competent person, the system just wouldn't accept that I was without a lot of paperwork and additional expense. The only place that did was Screwfix. who accepted me as an electrician for their piddling discount (but free coffee and ability to jump the queue at the desk) on production of my very ancient 15th Ed papers!

Can I suggest looking very carefully at the costs before doing this. Even at half the price, I doubt whether STROMA certification is at all worth it for a self-build. Years ago (15th Ed, so that'll give you an idea!) I used to teach (part-time) electrical engineering science, at City and Guilds, ONC and HNC level. I decided I may as well get my 15th Ed ticket (City and Guilds back then) so I could re-wire a house for someone. I did a lot of wiring work, and have kept up to date with the regs (and also kept several rolls of the old colour code cable.....................) and I reckon I'm a competent person, even though technically I'm not because I haven't paid all the money to join a certifying body and my test gear (although perfectly safe and adequate) doesn't meet the current requirements (what's wrong with a Megger and AVO?). Anyway, I thought about getting up to date as a competent person for our build, but it was too costly. In the end I found a self-employed electrician, who was just starting out. He had all new test gear, the Elecsa ticket, but not a great deal of experience of big wiring jobs on his own. I asked him to quote, said I'd do all the design, spec the fittings, get all the hardware, including the trivial stuff like cable clips, Wago's etc and could he quote on the basis of doing first and second fix, with a semi-useful "labourer" on hand to help. The total cost of first and second fix for our build, with the Part P paperwork registered and logged with building control, cost £1400 (he wasn't VAT registered). Clearly we got a pretty good deal, as there's a fair bit of wiring in our house (heat pump, MVHR, borehole pump, treatment plant pump etc) and he got some confidence-building experience of a fairly big wiring job. Might I suggest a similar approach if your hubby is already competent, but just isn't registered as such at the moment? I don't think I could have bought the new test gear needed, got the paperwork and paid one of the certification bodies for the £1400 I paid our electrician, in fact I think I worked out that a competent DIY job would have been around double that cost. Finally, building control are still "supposed" to be able to sign off DIY electrical work. There's a fly in the ointment in that the certification bodies have a problem with certifying someone to sign off work done by someone else, purely on an inspection and test basis, so you may find that building control are reluctant to take this on. Ours were quite upfront about this, saying that there was no one they knew of who could inspect and test to sign off against Part P that they knew of, so I would have to use a suitably competent electrician.

It seems I started something when I did this a couple of years ago, as an experiment (and it does work). As Nick says, you don't have to Y into the flush pipe. The flush pipe is open into the air space above the water level in the cistern, so you can just add a connection to the cistern, rather than the flush pipe. I used an unused knock out on the side of our cisterns to ft the extract pipes, there is a photo here: http://www.mayfly.eu/housebuild/part-thirty-two-more-on-mvhr-and-nasty-smells/ about three quarters of the way down the page. Space was a bit tight, so I had to cut things around a bit to get them to fit, and I also have to put some alloy self-adhesive tape around the lid joint to make the cistern a bit more airtight.

You do not need to ALWAYS use armoured cable outside, even underground. Look at your mains incomer - I'll bet it's just a bit of coaxial power cable, half the diameter of a bit of SWA and a good deal cheaper too. There are other outdoor rated cables available that are a lot cheaper and easier to terminate than SWA, and that can be run in a protective duct, or pinned to a wall, or provided with another form of suitable protection (cable conduit can be useful for protecting external cables in some locations and keeping it looking neat). SWA is a PITA to use, because of the challenges in terminating it (it has to be terminated with an SWA gland, and they are not the most user-friendly things ever invented). For cables run outside or underground in a protected environment (like a duct or conduit) then you can use NYY-J cable (see here: https://www.tlc-direct.co.uk/Main_Index/Cable_Index/NYY/index.html ) Not a great deal cheaper than SWA, but a heck of a lot easier to use!

Our ASHP makes less noise than the intake for the MVHR, or the externally wall-mounted PV inverter. I think ST heard it running full pelt when he first visited, as I seem to remember me turning it on as a demo. We both stood next to it chatting, and apart from the blast of cold air coming from the thing ai don't think anyone could describe a modern, inverter controlled, ASHP as noisy. The same isn't true for the non-inverter controlled ones, though. I've heard some of those (especially some of the re-branded Chinese imports) and they are a lot noisier, so I can see why the planners were concerned enough about the possible nuisance. Pity they don't show the same concern over the fitting of wood burning stoves, they are a bloody menace in weather like that last night and this morning, where, once more, our whole valley (and all the houses in it) is filled to ground level with thick wood smoke, from two or three houses in the village who have the things and don't give a damn about the nuisance they cause on cold, still, days.

As a tip, do as Peter suggests above and use the cheapest epoxy you can get - East Coast are often cheaper then CFS , but there is another place in Cornwall that's cheaper still - I used their stuff on my last boat build, Reactive Resins (here's a link - I have no connection with them other than as a customer: https://reactiveresins.com/epoxy-resins.html ) If you want dry sand (and as Peter says it does have to be really dry) then buy play pit sand from someone who keeps it stored inside. I've used it with epoxy to even up a workshop floor and it worked a treat. As another tip, play pit sand also works well with a cheap wet sandblaster, the type that's an attachment for a pressure washer, I've found. Finally, again no plug for profit, I can highly recommend the Reactive Resins floor coatings: https://reactiveresins.com/floor-coatings-screeds.html I used their epoxy floor paint and it was nice to use (no smell, water based) and very, very tough. It's what's going down in my new workshop, I'm not even going to think about using anything else. I would have reservations about their water-based two pack varnish, though, Synacryl. I used it on a boat and frankly it was crap, lasted less that a yeatr before it started peeling off badly.

Not really. If you look at the temperature the floor needs to be to deliver the heat required to the room in the depths of winter it will probably be no higher than around 24 to 25 deg C even in a house just built to building regs energy requirements. Our floor by the French windows can easily reach 35 deg C on a warm sunny day, so way hotter than any UFH will ever get. I think there's a load of tosh going around about UFH causing damage, as how many UFH systems run the floor surface at anything like the temperature it would get to when exposed to hot sun in summer? At our present house, the laminate flooring just inside the south-facing back door gets hot enough to singe your feet if we leave the back door open. I've never measured it, but would guess that it's way over 45 deg C.

1 - T&G is a lot easier when gluing down that clickfix - not so messy, quicker to lay, allows a wee bit of movement, etc 2 - IIRC, I used boards around 130mm wide. I found this an ideal width, especially when it came to cutting in around doorways etc 3 - You can easily make up 2 to 3mm with the adhesive, so I'd not worry about a few small low points, unless they were large in area (i.e. much more than the width of a board in diameter), in which case I'd probably look at filling them and getting them flat, first.. 4 - Yes, sealing the concrete helps a lot and makes the adhesive far easier to spread, too.

When this topic came up a while ago on Ebuild, I tried the "blow a bit of string down the duct" trick. It works fine. Use wool, with a few tufts of wool tied on the end to give some extra drag, and then use a vacuum cleaner on blow (I have an old one I use in the workshop that has the option to fit the hose on the outlet end). It's only the first couple of feet of the extract ducts that seem to get dusty, as someone else has observed. Anyway, once I'd got the bits of wool down the duct, I tied a bit of string to the end and pulled it back, so now all our extract ducts have a bit of thin nylon cord in them. these cords are all tied together inside the plenum end, and tied to the internal terminal at the other end. When we want to clean the ducts, another short length of string, with a big, home-made, woolly pom-pom in the middle is tied to the terminal end and pulled through the duct and then back again. It works very well, but only do this when you are due to do an extract filter change/clean, as all the removed dust ends up in the extract filter. It takes maybe 10 minutes per extract duct to do this, so maybe an hour's work all told, perhaps once every year or two. As an extra tip, make the woolly pom-pom a lot bigger than the duct. I made my first one only a little bigger than the duct bore and it wasn't that good. The one I have now is around twice the diameter of the duct bore, so is a nice tight fit.

Probably somewhere north of £1500/kWh of installed, usable, energy, I suspect, with a life of, at best, maybe 10 to 12 years. Lithium cells tend to be calendar life limited if only charged and discharged over a modest state-of-charge range, and that's anything between 1% and 3% per year capacity loss from age, so realistically they are probably not that much use after 15 years, and may well only last a year or two longer than the 10 year warranty period some give. Good quality wet lead acid cells, like Rolls, can last decades, but are cycle life limited, and realistically you would struggle to get more than about 10 to 15 years life from them. So, you need to factor in (on top of all other generation costs and equipment depreciation) a battery replacement cost of probably around 8p to 10p per kWh with most systems that are currently around. Add in the cost of the generation system, plus the maintenance and equipment replacement cost and you're probably up around 15p/kWh at the very best, and could easily be over 20p/kWh. Inverters and chargers are going to have, at best, around a 10 year life, maybe less than that, as their internal electrolytic capacitors have a hard life and even long life ones only have a maximum ten year life. Solar panels will easily last 20 to 25 years, a wind generator may well have a similar life, but will almost certainly be a constant source of maintenance, and that has to be factored in. If you can get batteries with a 30 to 40 year life, for around £1000/kWh of usable capacity, then that brings the cost down a lot. Assuming 30 years life (which is very pessimistic for NiFe cells) then you're looking at around 3.3p/kWh. If they were to last 40 years then the unit cost comes down to about 2.5p/kWh. Bearing in mind that that's the lifetime cost, with no inflationary increase because you've paid for the storage upfront, then that starts to look pretty good, even when all the ancillary costs are added in.

I worked with NiFe cells for years, ex-WWII era aircraft starting batteries, from ground start trollies. Nice to be able to mention them - mention them over on another forum and you get thrown off pretty quickly, as I found! The life of NiFe cells is phenomenal. I was working with very much abused cells that were, at best, made some time in the 1950's. They were still going strong in the early 90's, when we stopped using them and hadn't lost any capacity at all in that time, as far as we could tell. The downsides are that they take up a lot of space for a given energy capacity, as their energy density is poor. They have a relatively wide voltage change (in percentage terms) from fully charged to fully discharged. They use a strong alkali as the electrolyte, that is not pleasant to handle. The big advantage if that they would undoubtedly last a lifetime, perhaps with one washout after 30 years or so and a refill with fresh electrolyte. That means that the battery replacement cost can be, to all intents and purposes, removed from the balance sheet, as it's very unlikely that anyone would live long enough for the batteries to reach end-of life. They used to be quite cheap, when Edison were still making them, with the NiFe brand name, but I believe Exide bought the rights and stopped production, most probably because the last thing a battery manufacturer wants to produce are batteries that never need replacing! There are some manufactures in China making them, plus a firm in North America (can't recall whether they are in the Northern US or Canada). They are relatively easy to DIY, and there are some that have made their own cells and they work as well as the purchased ones. If anyone has source of the old telephone exchange glass accumulator cases then they form an ideal case for making NiFe cells. As Dave says, the killer with any battery off-grid system is the cell replacement cost. They all cost more per kWh than mains electricity, with the possible exception of NiFe cells, but they aren't that easy to get hold of.

I'm pretty sure there's an immersion heater element in some of these systems, to allow for PV top up, and a couple also allow for solar thermal input too, via a high efficiency coil, and that could be used with other low grade heat sources too. The bottom line is that really all these things are is a fixed speed air to water heat pump fitted to a water tank. They don't care where the inlet air comes from or the outlet air goes to. They are technically no different at all from a conventional (but rather small) monoblock ASHP, and work in exactly the same way. They do select a refrigerant that works better at higher air input temperatures, because the principle design point for these things (direct from an ESP bloke I was talking to, ages ago) is an air input temperature of 25 deg C and a hot water temperature of 50 deg C, where they will deliver a COP of better than 4. Like any ASHP, increase the temperature differential between inlet air and output water and the COP goes down, and also you start hitting the double whammy of getting defrost cycling. They get the high heat pump efficiency by drawing in warm air from the house, which maintains the low temperature differential needed. The key thing is to work well the house has to have a heating system that can provide the heat needed to feed the air inlet of the unit. There are several ways of doing this, but the major stumbling block is that when running these things use a LOT of warm air, far more than a normal sized MVHR exhausts. That has to come from somewhere. When you do the numbers, an exhaust air fed heat pump is barely better than an outside air fed heat pump in cold weather.in terms of efficiency, because, within reason, intake air temperature has only a small impact on the heat energy available for the heat pump to extract. For example, air at 2 deg C contains about 1% more heat energy than air at -1 deg C, or air at 20 deg C has about 7% more heat energy in it that air at 0 deg C. Right now the air coming out of our MVHR exhaust is only 3 deg warmer than the outside air temperature, and frankly that makes the difference in COP between an outside air fed heat pump and an exhaust air fed one negligible, and not worth the additional expenditure, in my view. I get a far, far bigger difference in COP from having an inverter controlled, variable output, ASHP, as that can modulate down and avoid the defrost penalty, something a fixed speed unit can't do. The variable speed advantage in efficiency terms is probably well over 10%, and that exceed any difference from feeding the thing with warm air. The downside is that all heat pumps only have a limited temperature differential over which they work very efficiently, and that's typically around 30 to 40 deg C. Any more than this and efficiency falls off, rather non-linearly I've found.. These integral water tank and heat pump units were designed for homes where there was plenty of heat available inside the house, and they work very well under those conditions. As other companies have found, trying to make them work well in a house that doesn't have a good heating system that is separate from the unit is challenging. Paul, for example, got caught out (or, more accurately, a UK agent selling Paul stuff who got his/her sums badly wrong) got their fingers burned when they installed a load of their very similar (functionally) exhaust air heat pumps in social housing. They found that the electricity usage was excessively high, because poor system design meant that the air temperature going into the unit was too cool and the unit was compensating by running its internal immersion heater a lot of the time to make up for this (the Paul and Genvex systems have an internal immersion that's automatically controlled by the built in controller).

Yes, it is the "on/off" nature of the heat pump in these things that is a part of the problem (and it's not just the Ecocent, the Genvex and Paul units similarly have a non-modulating heat pump). The basic units are extremely common in China, where there are literally hundreds of companies making them, and they are all very similar in design. The Ecocent was originally just a badged Chinese unit, but when I spoke to the guys from ESP (who are very helpful and technically pretty switched on) they told me that it was all made in the UK now. I have to say I have a few doubts about that, as there are physically absolutely identical units still on sale on Alibaba etc, and ESP has a long history of importing Chinese equipment, getting it approved to EU regs, and then re-badging it. However, where it's made doesn't matter, it's the "all or nothing" nature of the heat pump that's key. The reason for this is two fold. Firstly, these units are designed to replenish the hot water tank as quickly as possible after use, so there is always hot water available. Secondly it is a heck of a lot cheaper to build a non-inverter controlled heat pump, that only runs at a single speed. Depending on the pattern of hot water usage, an inverter-controlled version might well be a good option. For example, our major hot water demand is first thing in the morning for showers, then there is virtually no demand at all through the day, with a small demand in the early evening for washing dishes (just the stuff that doesn't go in the dishwasher) and very rarely an evening bath. A unit that could very slowly recharge during the day, drawing only as much heat from the exhaust of the MVHR as allowed by normal MVHR flow rates, would be fine for us, as our available recharge periods are always going to be 8 to 10 hours or more. The alternative, for those that need the maximum recharge rate, is to have a heating system that is responsive enough to increase its heat output in time with the additional demand that the water heating heat pump needs (I'm trying to be non-brand specific here, as this applies to all exhaust air to water heat pumps). There is loads of available energy in the MVHR exhaust, but to extract it at normal flow rates needs a very small capacity (or variable capacity) heat pump. The alternative is to increase the ventilation rate to get enough mass flow of air through a larger air to water heat pump. However, if the ventilation rate is increased, then the MVHR heat exchanger efficiency will drop, a lot, as heat exchange efficiency is very closely tied to flow rate. This means that incoming cool air won't get warmed anywhere near as much and so will be a lot cooler, and tend to cool the house down more than it would when the ventilation heat recovery system is working at normal flow rates. There is no good way around this. One sort of fix (and one that I think some systems use) is to draw outside air in and mix it with the MVHR exhaust, so that the MVHR doesn't end up delivering cold air. The downside with this method is that although the MVHR efficiency then ends up OK, the efficient of the air to water heat pump drops, as its inlet temperature is reduced by mixing outside air with the MVHR exhaust (which is always a couple of degrees warmer than the outside air). I've seen another fix where there was a valve fitted to the MVHR external inlet to just throttle the incoming fresh air, and allow air leakage to deal with the resulting flow imbalance. Clearly any incoming leakage air will be at outside air temperature, so will cool the house, but because it would probably be distributed over a lot of small, tiny, leakage points the effect may not be as obvious. For me, a small, inverter controlled, variable output, exhaust air to water heat pump could work well, as I could easily accept long recharge periods. I've looked around, and so far I've not found a modulating unit like this. My guess is that this is just down to demand. There is a massive demand in China for these things, do a search on Alibaba and you'll probably be as surprised as I was at how many manufacturers of them there are. Nothing in the Far Eastern market is driving manufacturers to invest in inverter controlled units, and I have to say that it's really only people with low energy homes, plus a pattern of hot water usage that allows for fairly long recharge times, that would really benefit from such a unit.

On it's own, it won't meet the ventilation requirements, for two reasons. Firstly, it only sucks air from the house when it needs to heat water, and that may or may not coincide with when you need ventilation. As an example, you may be cooking, so need extra ventilation, but the hot water tank may already be hot, so the ecocent won't run. ESP can combine it with a simple MVHR (like a few other systems that are available), which is sort of OK. When the Ecocent isn't running the MVHR works as normal, with the flows balanced and the flow rates set to those needed to meet the ventilation requirement. However, when the Ecocent runs the flow rates massively increase, and the MVHR goes way out of balance. The consequence of this is that heat recovery to the room air during these periods is very low, far lower than when the system is running normally. That's just a function of the way heat exchangers work, and can't be avoided. However, the impact this has may not be that massive, as you don't need to heat water all the time, only for a few hours a day, so most of the time the MVHR works normally, with normal heat recovery rates. The fact that the MVHR loses efficiency a lot for a few hours is still better than no MVHR at all, by a long way. To be fair, we should also include the other combined systems, like the Paul and the Genvex that are also MVHR units with an added exhaust air heat pump to heat hot water, as they all operate in the same way and have the same pros and cons. They are absolutely ideal if you have a house that has somewhere that's consistently too warm. As an example, we stayed in a well-insulated log cabin, with a wood burning stove. There was a mezzanine storage area in what could have been a small loft, and up there it was always like an oven. Drawing air from there to run an exhaust air heat pump for hot water would have been ideal, as it would have made use of what was probably a fair bit of otherwise waste heat. Someone on another forum has an Ecocent and (IIRC) they feed it with air that comes indirectly from a workshop (heated with a wood burner in winter) that's connected to a glazed sun room (that tends to get warm in summer) alongside the house and that feeds the air to the Ecocent. This results in virtually no impact on the house temperature, by making use of otherwise wasted heat to deliver hot water. I think the only issues I've heard of with this set up was the stainless tank in the Ecocent corroding and failing. IIRC there is a protective anode that needs to be regularly inspected and replaced when corroded, just like many stainless tanks.

Not sure there is a sweet spot, really. It largely comes down to the response time of the house heating system in being able to put back the heat sucked out by the Ecocent. If you're using a heat pump as the heat source for the house, then what you achieve with the Ecocent is a two stage heat pump, with a stack of losses, in effect, in the intermediate stage (the house heating requirement). To work OK, then the house heating system has to be able to respond to any heat loss quickly enough to not impact on the room temperature too much (there has to be some impact on room temperature as usually room temperature controls the "first stage" of this two stage system). You need to design the total system (heating and hot water) so that the heating system can deliver the extra power needed to provide the heat input to the Ecocent (a couple of kW or so) when it turns on. The idea above, of timing it to come on when there is an excess of room heat from the shower having been run is a good one, although it would naturally tend to come on then anyway because of the hot water use. To give a specific illustration, our house needs a few hundred watts of heat at most to stay at around 20 to 21 deg C. If we had an Ecocent we'd have to find a way to put three to four times more heat into the house whenever the Ecocent was running, and do it quickly. I could turn the UFH flow temp up; turning it to 28 deg C would definitely do the job OK in terms of additional heat input, but then I'd hit the snag I've already found; at 28 deg C flow our room temperature overshoots a fair bit when the heating switches off because the thermostat is satisfied. I dare not turn up our flow temperature above 25 deg C, and ideally I'd like to keep it around 24 deg C if I could, because of the overshoot problem. The problem is that the slab response time is pretty long, so when you start pumping heat into the pipes it takes a fair time for it to reach the surface and start heating the house. If the heating turns off, because the house is warm enough, heat continues to be released by the slab for several hours, as the warmer core of the slab slowly transfers heat to the surface and thence to the rooms. The less warm the core of the slab gets from the UFH, the smaller the overshoot problem.

I'd not expect the slightest problem with an Ecocent drawing heat from a house with that much heat input; your UFH is pumping many times more heat per unit area into the floor than our is, so the additional heating requirement imposed when the Ecocent turns on is pretty small in comparison with the other heat losses. That's the sort of application where exhaust air heat pumps, or room air draw heat pumps, work fairly well for DHW. Where they don't work well is where the house heating requirement is so low that the additional heat loss when the Ecocent turns on cannot be quickly accommodated by the heating system ramping up to push extra heat into the house. The Ecocent doesn't "make heat", it only sucks low grade heat from the house, that's been heated by some other means, upgrades it and heats hot water with it. That means it always has to draw around three quarters of the heat it puts into the hot water from the inside of the house, and that heat has to come from somewhere.

Yes, useful to know, as it means that the UFH can pump enough extra heat in to the house to make up for the heat removed by the Ecocent, something that bothered me in terms of response times. Out of interest, what's the UFH flow temperature? We keep ours at around 24 to 25 deg C maximum, as any higher tends to cause a fairly large (greater than 1 deg C) temperature overshoot after the thermostat's satisfied.

Me too, but that was really before GD became what it is today. I somehow doubt that they'd look at a build like that now - what on earth would RIBA think if they did! Then there's the "being parsimonious with the truth" thing, that particular afflicts GD, but does affect all of these shows (except, perhaps, Amazing Spaces and also, perhaps, Restoration Man). The one that stands out for me is the GD "eco" house, that had a SAP rating of G (!) and yet had the owner and Kevin McCloud spouting forth nonsense about energy efficiency and insulation. Remember the infamous Multifoil comment from him, that a 20mm thick bit of this "magic stuff" was equivalent to around 150mm (or thereabouts) of ordinary insulation? I generally like Building the Dream, except that I have a very strong feeling that some of the costs quoted are, like the kitchen example quoted above, more than a little fiddled. One theme of this programme has been that it starts out showing how building a house yourself can save tens of thousands. I'm sure it can for some, who get land at a good price and do a lot of work themselves, but I think you need to work hard to make a self-build come in at much under its market value. Our build is a reasonable example. I saved at least £50k to £60k by my efforts. These savings came from having no architect, no planning consultant, no project manager, only a couple of trades people and doing a LOT of DIY. Even so, our build came in at around £1340/m², which was more than I wanted to pay. Had I just used an architect, project manager, and had the house built for us by all the various trades, with no DIY from me, then the cost would have been somewhere around £2000/m². Had I been able to build the frame, foundations etc, and do more of the basic building work, the cost would probably have been down around £1000/m². Market value (including land cost) is currently is around £2500/m² around here, but this is an expensive bit of the local area. Where our old house is, market value is around £2000/m² generally, depending very much on the exact location and size of plot. I wonder how many self-builders really save a load of money by self building? Only those who get a cheap/free plot, or who do a heck of a lot of work themselves, I suspect.

First off, these programmes are all entertainment, and most are made on a very,very tight production budget. They are almost as cheap to produce as quiz shows, I suspect (although quiz shows take some beating for being budget TV). It's no accident that there are so many of these shows around, now, they've proved popular and are very cheap to produce - a winning formula for anyone commissioning a programme for a TV channel. They are also, like many quiz shows, very much "ego TV", in that generally they don't pay the people whose projects are really the stars of the shows, any money at all, they rely on some people "wanting to be on TV", and not caring about getting paid for it. FWIW, you don't get paid much for TV work anyway, unless you're a big name. I think I was paid something like £400 per episode for Scrapheap, which worked out to less than £10 an hour, and the same went for all the production crew, who were mainly self-employed and charging pretty modest rates. They have all developed, or aimed at, target audiences, and those target audience aren't self-builders at all. There aren't anywhere near enough self-builders in the UK to get a commissioning producer interested in buying any show aimed at them, so the audience for all of these shows has to be massively wider than that for them to be commissioned. GD has focussed on mega-projects in the main, with a few oddball ones thrown in, and the appeal of the show is also partly driven by the presenter (although my other half can't stand him!). Their target audience is similar to those who buy some of the up-market home magazines - mainly "lookers, not do'ers". It's notable that quite a few architects use GD as a way to gain free publicity for their work, as there seems to be a higher than average proportion of architects and designers on that show, plus it seems closely tied to RIBA. Building the Dream is plain "aspirational entertainment", the sort of show that thousands will watch in daytime re-runs for years to come, and which appeals because it seems as if the projects are, in the main, within the reach of many ordinary people. It has a target audience that's probably pretty close to being the same as that for the programmes on doing up houses, etc, and it's a bit like some of the "chat" magazines, in that respect. Amazing Spaces is really about how small a space you can do something with, and a fair few people can probably relate to it, as it is about making use of small spaces efficiently, and a large number of UK homes are pretty small. It's also got the "wacky factor", in that it features some stuff that's pretty weird and wonderful, and there is a fairly large target audience for anything out of the ordinary. I'm friends with a former ITV and BBC Commissioning Producer (I worked for him on a BBC project that was part of H2G2 many years ago), and he reckons that the viewing target market has to be in the several millions of views (that's total views, both original broadcast plus multiple repeats) before anyone will commission a new series. Self-builders amount to a few thousand a year, I suspect, so nowhere near a big enough market for any TV show, hence the reason that these shows are aimed to entertain millions of people who will never contemplate a self-build for real.

A couple of weeks or so ago I sat down and worked out my "over-thinking time", as a rough estimate. I reckon it was over a year of working time, just spent either finding out how to do things, or doing things, getting them wrong, and having to do them again. The problem is, even having done one self-build doesn't give you more than about 20% of the knowledge you need, just because every house and site will be different, and pose different challenges. One thing I can understand a bit better now is why the developers build boxes that are very similar, and will only build on clear and easy to access sites, with known ground condition. It means they don't have to deal with the wide range of issues that most self-builders have to deal with.

It's a great shame that you blocked PMs from me, as I mentioned earlier this is a topic that would be far better discussed privately. I'd be more than happy to speak to you on the phone, where you could tell me exactly what it is you think I posted that was "downright outrageous" about a company that no one I know of has ever traded with. I have a full copy of the "Ebuild incident" posts, and having read through them there wasn't a single one by me that was in any way outrageous, untrue or the cause of the problem that evening. There were revelations by others in that thread that were contentious, including one that was most probably unlawful under the rehabilitation of offenders act, but none of those posts were made by me. The thread wasn't started be me, either, FWIW, it was started by someone with an innocent wish to let people know about a trading relationship, nothing more. A simple Companies House check on the web will prove the one point I made on that thread that could have, but as it happened didn't, cause the problem. I will publicly apologise for my loss of temper in December, as I have done, more than once, to all the other founding members. I was out of order, and the cause was not something I'm going to go into detail about in public, suffice to say that I over-reacted to what I mistakenly thought was post censorship and moderation policy, a subject that had been sensitive in July last year, when I took a break from posting here to get on and sort out some stuff in my private life. To answer your question about post numbers that show here, the answer is that I had nothing to do with changing them, have never had the permissions here to do so, and it was a bit of a joke from when the forum first went live, as I recall. When the software here was being set up and tested, someone (not me) asked a question about the post counters and one of the Admins said they could be initially set to any number. Someone in the founding group (I honestly can't remember who - it was a discussion on the temporary private forum the 16 of us used before this site set up) suggested that we should all start off with the same post totals as we had on Ebuild, so that's what was done. If you look around, then you'll find that all the founding members here had their starting post totals set up like this, as far as I know. It was intended as a bit of a joke, a bit like another forum I'm on where every post in a certain section subtracts one from your post count that's shown, but if it causes offence to enough people I would guess the Admins here could sort it out somehow. I would rather we clear the air about this, and be completely open and honest, rather than have anyone with lingering doubts as anyone's motives, actions or whatever. FWIW, I'd prefer straight-talking and absolutely detest secrecy unless there is a very good reason for it, so your final comment to Ed about re-posting this is fine with me, and is what I would have done myself in your circumstances.

Just to be clear, if he still holds the same view after he's read everything that's circulating by PM, then that's absolutely fine by me. It was the thought that, like lots of former Ebuild members, he didn't know very much about went on over that 24 hour period that concerned me. There were a heck of a lot of rumours flying around, and some normally very calm people lost their tempers over what they thought was going on at the time, including me when I was penalised when all I'd done was get proper (and free) legal advice, as a way of trying to help. It's slightly off-topic, and is in the forum rules (I know, because I put it there when I wrote them) , but still worth a reminder here, I think, as it's pertinent to the point being made. If you write something in a post on a forum, and that is defamatory, or even libellous, then it is you, the poster, that is the person that legal action can be taken against, under normal circumstances. Those of us that started this forum will remember the debates about this, as it was in the front of our minds after Ebuild closed, but the law is very clear, a forum owner cannot normally be held responsible for the content of posts, except under some exceptional circumstances. None of those exceptional circumstances applied in the case of Ebuild, and not one single post that remained in that on-line debacle was libellous. At least three made by the protagonist and instigator of it were potentially libellous, but the moderators had removed them very quickly (within minutes) and so no significant harm was caused. That's not my view, that's the view of the judge who read it all and pronounced on whether or not anything was actionable in his legal opinion.