Jeremy Harris

My decision to not bother with a warranty was based on my experience with NHBC being a waste of time (bought a new house years ago and found out the hard way that the NHBC warranty wasn't worth the paper it was written on) and the fact that the next house we bought was someone else's self-build, with no warranty, and all our lender needed was a single premium insurance policy from the vendor, that cost them less than a warranty would have. We have no intention of selling, but I'm quite happy to just buy a one-off insurance policy if we absolutely have to sell within 10 years of completion. The chances are that would still be cheaper and less hassle.

You don't need to worry too much, aerobic bacteria are a heck of a lot tougher than the anaerobic bacteria found in old septic tanks, and about the only real concerns are putting solids into the plant that won't digest (basically anything like wet wipes, or sanitary products) and restricting the use of anything containing a lot of chlorine based bleach. Even then, the plant will tolerate a squirt of bleach around a toilet bowl from time to time, as by the time it's been diluted by the flush and flowed down to the plant most of the chlorine will have come out of solution, anyway. There's no problem with ordinary dishwasher or washing machine products at all, AFAIK. A treatment plant works in the same way as a big sewage treatment plant if you were on main drainage, with the exception that it doesn't have any solids screening at the inlet side, hence the need to make sure that nothing that isn't soluble goes into it.

As @PeterW says, you do have to insulate the pipes, and make sure any joins in the insulation are well taped up. I find that we do get a little bit of condensation on the UFH manifold, but not enough to cause any drips, it just mists up slightly, like a mirror in a bathroom. I did think about making a box around the manifold, with a perspex front so that the temperature gauges and flow meters can still be seen, but I don't think it's worth the hassle. The floor under the manifold is tiled with travertine, and there's a bit of PVC angle bonded to the wall/floor joint to stop any moisture getting to the wall (I did the same behind the kitchen units and around the space that the washing machine slides into), so even if there was the odd drip of condensation it wouldn't do any harm.

Probably not. It's really not that hard to DIY, though, as along as the installation has provision for isolating any buffer tank when in cooling mode. I just fitted a motorised ball valve in the flow to the buffer tank, so that tank stays warm when the ASHP is running in cooling mode. I have two remote control thermostats mounted on the hall wall, one sets the heating temperature the other the cooling temperature. The heating stat switches the ASHP to heating mode, the cooling stat switches it to cooling mode. I did need to programme the ASHP with the cooling and heating temperatures, but some delving through the manual showed how to do that fairly easily. Our ASHP is a Carrier, but badged Glowworm, and is identical to the other ASHPs also made by Carrier that carry badges like Kingspan. Often UK installers may not be familiar with operating ASHPs in cooling mode, unless they are used to dealing with office type installations. Our old offices had chilled water passive coolers in the ceilings, basically just like radiators mounted on their side on the ceiling with chilled water running through them, but with condensate trays to collect and drain away condensation from the cooled surfaces.

Apparently it was partly filled with building materials. I found it listed on ebay yesterday, with bids up around £300, but the listing seems to have gone now.

Underfloor cooling works well, in my experience. Pretty much any ASHP can be reversed and become a cooler, as they do this normally to defrost when in heating mode. It may not be well documented, it depends on the model, but I found it very easy to switch ours from heating to cooling. In cooling mode I have it set for a flow temperature of 12 deg C, which means that in practice the floor temperature never drops below about 18 deg C, which in turns means there's no condensation risk at all. It's most effective where the floor might otherwise be heated up by sun coming through glazing, as by stopping that area of floor from warming up it prevents heat from the floor being convected into the air in the house. Another fairly simple way to add air cooling, if you are fitting an ASHP, is to fit an inline duct heater/cooler into the main fresh air outlet duct from the MVHR. This then allows the MVHR to deliver cool air to all the rooms whenever the ASHP is running in cooling mode. It doesn't shift a great deal of heat, as the MVHR takes a couple of hours or more to change all the air in the house, but will probably remove around 1 to 2 kW of heat at a guess, which may well be enough if the house insulation has a nice long decrement delay. Decrement delay is more important than U value in many ways, so well worth looking at during the design stage. Duct heater/coolers look like this, and should be easy enough to plumb in:

If it's not a TCT blade, then using an angle grinder whilst the blade is spinning on the table saw should work OK. I've done something similar with a Dremel grinding wheel on hardened steel spinning in the lathe - it's the way I sharpen centre punches, just to save softening them, turning a new point, then hardening and tempering them again. I wouldn't try it with a TCT saw blade, though, as they will chew up the angle grinder and probably spit bboken TCT blade tips out, as the brazed joints holding the TCT tips give way.

My identical Glowworm doesn't have AV pads either, and the MIs just say bolt direct to the concrete base. I bolted mine directly down with thunderbolts and there's no noise or vibration at all. If you look inside you'll find that the scroll compressor is mounted on internal AV mounts, which is presumably why the MIs make no mention of fitting the unit on AV pads.

I bought a cheap'ish, fairly large dish (larger than needed for our area) and I was surprised to find that the LNB arm was made from a pretty robust alloy box section, complete with a built-in spirit level. The dish and mounting bracket seem to be powder coated zinc plated steel, and there's a neat plastic socket inside the steel bracket at the base of the dish where the LNB arm bolts, presumably to prevent galvanic corrosion. I bought it from ebay for around £40, complete with a quad LNB, and it looks like it will last for many years. TBH I was a bit surprised, as the quality of the powder coat and the bolts that hold it together look as if it may well have been made in Germany - it has that well-engineered German look to it. I'm no doubt that it would be fine in an exposed location, as long as the mounting tube was secured to something very rigid.

Freesat get's my vote, too. My experience has been that it's 100% reliable, dead easy to use and there shouldn't be any problems with having a dish on Skye - IIRC, Paul Camilli out on Raasay relied on a dish for internet connectivity for a time, and his place is pretty exposed.

Even that's far from ideal, it's not wholly open source, and relies on users trusting the element of closed source code that it uses.

No, unless you happen to have an "old school" inspector! The falls should be on a full plans submission anyway, at least indirectly, as the invert levels at key points in the foul drain run are supposed to be shown on the plans. With these, and the scale on the drawing, the fall can be calculated. What seems to have happened is that the guidance on falls has changed sometime over the past couple of decades, but this hasn't filtered through to those applying the regs very well. There are still well-respected sources telling people that they need to install a back-drop chamber if the fall is steeper than 1:40, for example, despite the fact that it's been shown to be OK to use steeper gradients. I'll admit to being caught out by this myself, as back when I first installed a foul drain run the "between 1:40 and 1:80" rule was strictly applied. I only realised it had changed, in the light of evidence from more recent testing, after someone posted here to point it out. Part H makes no mention of steep falls being a problem now, so if an inspector gets a bit uppity about it, just show them what's in the Approved Document.

My main concern with Windows 10 is loss of privacy and granting Microsoft the right to read and copy any file, email, bit of data or whatever that's stored on your machine, be it on the hard drive, USB stick or whatever. Because it's written into the terms and conditions that you agree to when installing W10, even if you opt out of their "customer experience program" and try to turn off all the data gathering and telemetry, Microsoft will turn it all back on again with the next update. Anyway, the user-accessible privacy options on W10 are a bit like the buttons on some traffic lights at pedestrian crossings, they give you a feeling that you've done something, but the reality is that you haven't. For those who don't read all the dozens of pages of the terms and conditions before installing software, then this is just an excerpt from the Windows 10 Ts and Cs that might just give you pause for thought: Microsoft are moving their business model from one where you pay for an operating system licence to one where they earn revenue from your data, much like Facebook does, and Google does, especially with Android (Android constantly streams data to Google servers all the time, I found, even with all the privacy settings set to turn off as much data sharing as you can). Right now, Microsoft are adamant that they are not sharing the data they collect from you with anyone else, but it's very clear from the terms and conditions above that if you install and use W10 you have given them explicit consent to access any of your data they wish. Personally I feel this is a bit OTT, not because I have anything that I want to hide, but just because I would rather that the content of letters I draft to my doctor, insurer, bank, etc remain private, and don't end up having data extracted from them that ends up in a big dataset about me that Microsoft (or whoever) use to generate revenue. Although not a fan of Apple, by any stretch, they do seem to be probably the only big company in this sector that isn't (yet) exploiting user's personal data to generate revenue, and they seem to take personal privacy concerns a bit more seriously. The only other alternatives are to go open source and run Linux, or, with very great care, stick with an older version of Windows. Be aware that if you have updated Windows 7 regularly, then you will have added the update that has been rolled out several times over the past couple of years that includes data gathering and telemetry back to Microsoft. Whilst this is not as great an intrusion into your personal privacy as installing W10, it still passes lots of data back to Microsoft servers. The good news is that it's not too hard to remove all the updates that only send data back to Microsoft, although it is a bit tedious, as there are a lot of them and removing them is best done from the command line, with admin privileges. I still run Win 7 and have removed all the "telemetry" updates, plus I've blocked all the Microsoft (and Google) related data gathering servers in my router (another tedious task). There are plenty of instructions on the net as to how to remove telemetry from Win 7, but this is not an option for personal users of W10. If you can get hold of an enterprise version of W10, as released to companies and organisations that must have secure operating systems (although I'd question whether anything Microsoft produce is really ever secure) then it won't have any of the telemetry or data gathering capability activated, so won't keep "phoning home" to Microsoft all the time. Sadly, I don't think there is any lawful way for most personal users to install and run the enterprise versions of W10. For mobile devices, LineageOS is easily as good as Android, runs a fair bit faster and, as long as you don't do something daft, like install Google Play Services or the Google store, then it doesn't share any data at all with anyone unless you specifically give an app permission to do so. The only real downside is that apps (that you trust!) have to be installed by side loading APKs, but that's not really a major issue. I've been running LineageOS, and it's predecessor CyanogenMod, as the operating system on my Sony Xperia tablet for a fair time, and it's much faster than Android, uses a lot less data when I'm out and about using a mobile connection (presumably just because of the absence of all that "phoning home" to Google every few seconds, using up your bandwidth and data allowance) and best of all, the battery life improved by around 20%. I'd be the first to say that it's a bit of a faff to root your device and load the new OS, but there are lots of useful tutorials on the net, and it only takes an hour or so to do. Some of the open source apps are really very good indeed; I particularly like OpenStreetMap, as it doesn't need a data connection to work - you can opt to download chunks of map data for an area that has a poor mobile signal beforehand, and the data set seems to be as good, if not better, than Google Maps. It's also faster, at least as far as my very limited comparison testing (before I got rid of Android) indicated.

I solved this with rolled up balls of chicken wire, with a bit of heavy gauge fencing wire threaded through the centre and twisted back in itself. What you do it feed the pipes, cables etc through the ducts, then poke the ball of chicken wire down, with the heavy gauge wire poking up. Then use expanding foam to seal the duct on top of the chicken wire, again with the heavy gauge wire poking out. Do this at both ends of every duct, although there's no need for foam on the outside ends. The ball of chicken wire should act as a pretty effective rodent barrier. If you ever need to run another cable or pipe in the duct, you can just pull the ball of chicken wire out using the heavy gauge fencing wire as a handle. The foam seals the ducts up reasonably well, but doesn't adhere that well to the inside of the duct surface, so can be pulled out (I've already had to do this to one to run another cable in). I finished off over the foam with some airtightness tape inside the house, but I don't think it's really needed, the foam does a good enough job.

Thanks for spotting the error on the spreadsheet, I'll fix the wording and post a revised version up later. Well done for spotting it, too, as I wrote it years ago and must have used it loads of times when refining the detail design of our house, I didn't once spot it - must be going blind!

I also found building control to be (with one exception) very flexible and helpful, who didn't seem at all bothered by our pretty long build time schedule at all. All told I found that our first and last building inspectors were very helpful indeed, and our BCO was both quick to answer some often unusual questions as well as always offering advice that was first rate.

On the couple of occasions I've used Citizens Advice they were great, but that is some time ago. I found this link that may help: https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/problem-with-home-improvements/

Best bet might be to ask Citizens Advice on this. Often they have access to a pro bono solicitor who will give 30 mins of advice for free.

Easy enough, but you do need to refer back to the BCO (not the building inspector, usually) and provide additional information to show that the modifications meet building regs. Main issues are like to be Part A, Part B and Part M.

They did for me. I pointed to some standard approved details for things like the rafter/ridge beam detail, and the fact that our house frame was signed off by the frame company's SE satisfied our BCO, although I did need to point out that we had an agreement in the UK to accept NSAI certification (NSAI being the Irish certification for timber frame construction) as being equivalent to UK certification, and vice versa (our frame was built in Ireland).

@jack, I think you really have three choices at the moment. You could choose to use a mediation service ( http://civilmediation.justice.gov.uk/ ) and see if that resolves things without you needing to deal directly with the insurer You could just file a claim online against the supplier, using the small claims track, which is fairly easy to do if your claim is for a fixed sum ( https://www.gov.uk/make-money-claim ), or you could send a registered letter to the supplier, telling them that you refuse to deal with their insurer, as is your right in law, and that they have a fixed period of time to settle the outstanding claim or else you will be making a claim via the small claims track. If it were me then I would avoid dealing with their insurer, and insist on dealing with the company directly. Their insurer will try every trick in the book to slow the process and avoid paying out - I do work for some insurers and have seen first hand how they try their damnedest to avoid paying out. The "incompetent staff" trick is often just that. They try to make sure that anyone dealing with a claim by one of their clients customers seems to be less than competent, with documents being "lost", emails being claimed to have been sent when they weren't, phone calls made that weren't, you name it.

Too late, I know, but when we first started thinking seriously about self-build, around ten years ago, the first thing I did was think about the type of house we would want, and do some research on that, the second thing I did was join this forum's predecessor, ebuild, and make a bit of a fool of myself by asking some pretty dumb questions. Luckily, that forum , like this one, highlighted lots of things I needed to consider, and the one thing that kept recurring was that there were potentially major cost risks that needed to be mitigated, and that builders/main contractors/project managers/architects were consistently poor at managing the price the client ended up paying. I gained the very strong impression, pretty early on, that managing the risk of going over-budget was going to be really bloody hard. That was reinforced by having watched every episode of Grand Designs, where busting the budget seems to be a feature of the majority of builds they show. When we found our plot, my main priority, bar none, was nailing down the prices we were going to have to pay for the various stages of the build. I probably put more effort into taking risk out of the build than anything else, and it very definitely influenced the way I contracted for every major build area. Our ground works contract was done to a firm price, against a very well defined specification, with no variations at all to be undertaken with out written consent and an amended firm price. The same applied to the water supply borehole, and also to the house foundation and erection to watertight stage, we had a detailed contract that included drawings and written specifications, with an agreed stage payment plan and the exact definition of the work that needed to be completed in order for that stage payment to be made. The roofing, fascias and guttering were also done to a tightly defined written specification at a firm price, as was the window supply and fitting and the solar panel installation. It was only when that work was completed that I changed to getting some of the smaller jobs done to a firm price, some done on a day rate, as by that time I had a better feel for the way the building industry works. The upside of this approach was that I knew what all the major costs would be upfront, the downside was that i probably paid a little bit more for the ground works as they included a risk contingency in their costing that they didn't end up incurring, but I'd heard so much about unforeseen ground works cost problems that I had already decided that the ground work risk was not one I wanted to bear, so would rather pay a bit more to get a firm price, with no risk to us. We did run out of money towards the end, but only because we opted to go for higher spec stuff. We went about £5k or so over budget on the kitchen, maybe £1k over on the bathrooms, about £2k over on internal joinery and at least £5k over on the landscaping, partly as a consequence of the unforeseen actions of a neighbour cutting down a 30ft high hedge and creating a major privacy problem. We also incurred an additional cost of around £4k to £5k in trying to keep a neighbour onside, which, with hindsight, was not a good move at all. All the over-spend (around £17k to £18k), plus around a year of delay caused by problems with the borehole, meaning I did a great deal of work that really should have been done by the borehole company, ended up being paid for by saving up money each month from my pension, and doing the work as I could afford it. All told this added at least two years to the build, which itself increased cost, as we have been paying Council Tax for over a year now whilst I slowly finished off some of the extra work.

Thanks for this, it looks very interesting. Not sure about using a RPi, though, as it's not really optimised to handle network traffic. I wonder if this will migrate to OpenWrt/LEDE? Running it on router hardware seems to make more sense, and would avoid the need to have another box in the network connection. I've already got a cheap second mini router running TOR that gives me the option to connect via TOR without having to run the TOR browser (although it does still need a safe browser to be used to limit browser profiling - I use a portable version of Firefox that is set up to run from a USB stick, with all the usual safeguards that are in the TOR browser version of Firefox.

As above, I'd go for a full plans application, as it's damned risky to do a new build on a building notice and could easily cost more on rectification following a failed inspection than the costs of preparing a full plans application. I did all my own drawings etc and submitted the full plans application myself. At a guess it was probably a couple of days work initially, plus a few hours spent answering a few questions from building control. If it's any help. everything I submitted for building control approval as a full plans submission is here: http://www.mayfly.eu/2013/09/part-fifteen-the-site-is-finally-ready/ I didn't have to buy any software as I already had a copy of AutoCad, and have been using it for decades, and the design SAP was done with the free version of the Stroma FSAP software, which is fine for the design submission, as there is no requirement to use an accredited assessor at this stage, and the software isn't hard to get to grips with.

It's certainly hard to think of something that could happen after five years to cause this. I reckon that going through the diagnostics using the Command Unit connected might be the best way to track down the sequence that's causing the flow error shutdown. One problem is that the final errors shown on the diagnostic LEDs may not be the actual cause, as one fault can lead to other error messages due to the knock on effects it creates. The big problem is that if it takes 5 hours of running before the thing throws an error and shutdown, you could be there for ages trying to track it down. The fact that it's affecting two units at the same time seems really odd, too, and makes me wonder whether it's something other than the heat pumps that's causing the fault. Equally odd is that when the error occurred 30 months ago you had to replace two flow switches to fix it, it seems a heck of a coincidence for two to fail together. Any chance of a system diagram to try and have a look at what might possibly be the root cause of this?