Jeremy Harris

I run ours as a single zone, with a single channel time switch/programmer controlling the power to the pump and to the two thermostats (one for heating, one for cooling). The timer sets when water is circulating around the UFH loops, irrespective of thermostat settings. The thermostats control whether heating or cooling is selected, setting the appropriate connections on the ASHP and to the valves. It uses off-the-shelf parts, and the most likely control system parts to ever fail (timer, valves, relays and thermostats) are all off-the-shelf standard parts, that could be replaced quickly and fairly easily if there was ever a problem.

My view is that this thread has now run it's course, and that the summary that @recoveringacademic has carefully compiled here: should be considered to be the definitive source of information for self-builders. For those who are not self builders, but who are building as a part of a business, and so are bound by CDM 2015, as they are not domestic clients, then I would suggest that it is very unsafe to rely on information from an internet forum when it comes to getting legal advice. I'd also add that relying on any legal advice obtained from someone not practising law is also inadvisable. I've seen several accident cases where individuals made assumptions as to their liability based on advice obtained from the media, friends and even consultants, that proved to be wrong and ended up costing them dearly. Self builders are, by definition domestic clients as far as all building-related legislation is concerned, and the guiding principle to be remembered is that legislation aimed to improve the safety and welfare of workers on construction sites, in whatever statute, is not intended to apply to someone who is a domestic client. The sole exception to this is the law that covers each and every one of us every day, with regard to the reasonable duty of care we each have to each other. It is worth remembering that the word "reasonable" has no definition in the law of England and Wales (not sure about Scotland and NI, but I think it's the same). If you are an ordinary citizen, with no specialist training or knowledge, then what is considered "reasonable" in terms of your actions or inactions will be judged on that basis. As soon as you seek to acquire recognised skills and knowledge that means that a court may consider that you have an enhanced duty of care your liability increases. As an example, I used to teach electricians at technical college many years ago, and for years held a ticket myself. Even though I no longer hold a valid chit to work as an electrician today, I would still be considered by a court to have a higher duty of care to others in terms of electrical advice than someone with no such experience. It's the reason I spent a great deal of time clarifying certain points in my blog, after making a typo here that was picked up on and used to condemn me as giving dangerous advice. I felt strongly enough about making sure that my own liability was reduced as to not only quickly correct the typo but also to spend three days writing two articles to clarify things. Those articles were not written from the goodness of my heart, they were written to reduce my personal liability!

It is not valid for domestic clients. Quite why this keep being raised again and again is beyond me. The law is clear, with no ifs, buts or maybes. It's almost as if someone is trying to sell something that self builders neither need or require.....................

You cannot appoint or contract with someone to take on a role that devolves you of responsibility that the law requires you to hold. However, as a domestic client you cannot lawfully assume any responsibility. Therefore you contract with someone to take on a task, and one part of that task consists of assuming certain legal responsibilities. For example, you contract with a main contractor and the main contractor, because he/she has offered to take that role, has, in law, to accept the responsibilities that go with that contract.

The Ecology BS are extremely good to work with, but you have to meet their requirements. I found them absolutely superb in every respect, and their interest rates are reasonably if you are building a house that complies with their terms (we were). The best thing about them is that you deal with a real human being, the same one through the whole process, and they are fairly flexible in terms of looking at every application on its merits. Buildstore are a complete bloody nightmare, no way would I even entertain ever using them. We used them for insurance, and that was both ludicrously expensive and tied us in to a deal where the renewal premium when our build over-ran was just crazy, around 150% more than the initial premium, and they try to lock you out of getting a quote from any other broker. The words long, barge and pole come to mind when describing them. Nothing would ever induce me to deal with them again, or suggest anyone else does.

First off, you cannot touch, move, disturb or otherwise interfere with bats, of any species, unless you are licensed to do so. If you do, then it's a criminal offence, with a hefty penalty. So. the first thing is to gather information, and then you have to get a plan of action formulated that ensures you stay within the law. If the bat roost is determined (by an expert) to be a summer roost, then you cannot do anything until the late autumn, when the bats will move to a hibernation roost. If it's a winter hibernation roost, then you can only take action during the summer, and will still need a licensed person on hand as the roof is dismantled (which must be by hand - no ripping it off with a digger!). The licensed person will rescue any trapped bats (often they will be under the felt, perhaps between the felt and the tiles). So, the first thing to do is look at the ecology report and see what it says about bats. If you are very lucky then it may be just a temporary feeding roost, which is the least onerous as you only need a licensed bat person around whilst you dismantle the roof by hand. If it's either a hibernation roost or a maternity roost then you are in for a long and expensive load of hassle, I'm afraid...............

The simple answer is that if you appoint someone then you are accepting some liability, because the act of appointing someone implies that you are sufficiently knowledgeable as to understand whether or not that person has the skills, experience and training to undertake that role safely, and in accordance with the law. If you contract with someone, as a domestic client, to do the same task, then the law does not expect you to have the knowledge or experience to judge whether that person is competent. The liability rests almost wholly on the person you contract. Here's a couple of non-building related examples, by way of an illustration: You are working in an amateur dramatic association, with other people. You appoint someone to erect a scaffold tower to paint some scenery, because they are the nearest person to you at that time. They do as you have told them to, and erect the scaffold. The scaffold collapses because it was incorrectly erected. Both the person that erected it, and you, share liability. Before appointing the person to do the job you had a responsibility to determine whether they had the right skills and training to do the task. You are working in an amateur dramatic association, with other people. You place a contract with someone you believe to be competent to erect a scaffold tower to paint some scenery. They do as they have been contracted, and erect the scaffold. The scaffold collapses because it was incorrectly erected. You almost certainly bear no liability at all. You placed a contract in good faith, and had a reasonable expectation that the person you contracted with was competent.

The building regs changed slightly for the most recent iteration, nowhere near as much as they need to, IMHO, as they are still crap in terms of energy performance, but the requirements of Part L1a has become a little more challenging to meet with way that heat loss is now determined. In the past you could just build to the fabric minimum standards (which haven't changed in the latest iteration, they are still poor) and be reasonably sure that you'd get a pass. Doing that now probably won't get a pass. For a large house, lack of airtightness will be the biggest heat loss, in all probability, so improving this can reap a really big benefit. The air leakage requirements in Part L1a are not great, 10m3/m2/hr at 50 Pa pressure differential, which isn't very airtight at all. It's easy to get better than 3m3/m2/hr with decent detailing - our house achieved a reasonable figure of 1.22m3/m2/hr, for example. In all probability, ventilation heat loss (with poor airtightness and no MVHR) will be the lion's share of your total heat loss, so designing for good airtighness from the very start (which means selecting a build method that is intrinsically easy to make airtight) will both reduce build cost (in terms of reducing the time taken to tape and seal to get the required air test figure) and make it easier to both meet the requirements of Part L1a and make the house a great deal more comfortable and cheaper to run.

My guess is that their ground works ate up a fair bit of the budget. Had they been sensible, and done some basic checks as to where sewers, pipes, cables etc were under the plot (all of which could have been done before the auction, in all probability) and done a bit of research as to what used to be on the site in years gone buy, they could almost certainly saved themselves a lot of grief. I suspect the reason that they managed to buy it at auction was because there was no local builder will to pay anything like £107k for the plot, knowing that if he/she did then there would be no profit in it.

@Ian, thanks for that. That's exactly what I'm hoping to achieve by moving the pump into the small stone block house! We have the same Secoh pump, too.

I will only add that, as the former manager of multi-million pound contracts in my old day job, there is absolutely no way that I would take the risk, as a self-builder, of appointing anyone into any legally binding role. It's a minefield of potential personal liability, and one that self-builders are very well advised to stay well away from, and let their contractors sort out amongst themselves, as they are required to by law.

My advice would be to completely forget about having any sort of trickle vents in the windows, forget bifold doors as they will leak like sieves within a year of being fitted, and go for the very highest spec 3G glazing you can get, in the very, very best frames. Even then I think you might be really struggling to get a SAP pass, even with MVHR. Architects aren't always the best to do the system engineering work needed to make a house both comply with Part L1a and to ensure that there's no over-heating risk, as traditionally some architects would just chuck that "over the wall" to the engineer doing the detail design. That often doesn't work now that the requirements of Part L1a have been slightly tightened, as you can't just build to the minimum fabric performance standards and get a pass, as you used to in the past. I'd very strongly advise doing a design SAP right now, and seeing what the number are. With lots of glass it can be a real struggle to get the house to pass, which basically means no house, even if you have got planning permission and have built it. You don't want to find out after the design has been finalised that you're not going to be able to get through building regs. Sorry, I missed this earlier: In essence, a fixed price contract is not a "fixed price", but a firm price contract is. It's a bit confusing, but a fixed price contract (in English and Welsh contract law) has allowances built in for price variations, caused by things like exchange rate variations, changes in supplier costs etc. A firm price contract has no variation in price as long as the specification remains the same as that originally quoted for (which is another issue, as everyone always changes the specification as they go!). There is another contracting mechanism that I think works very well for expensive projects, and that's to opt to have a target cost incentive fee contract. This has a target cost, agreed by both parties at the start, and backed by a good QS, then an incentive arrangement agreed with the main contractor for any cost saving achieved over the contract duration. For example, you might set a target cost of £500k, and agree a 50% incentive fee. That mean that if the main contractor comes in at, say, £480k, then he gets £490k and you save £10k (the £20k saving is split 50/50 between client and main contractor. Managed carefully, such a contract can be a fairly good way of controlling costs, or even allowing for a higher specification if the main contractor can show a saving early in the build.

My guess is that the neighbour will get over it in time. It takes a lot of bitterness to stay angry for any length of time, and the bottom line here is that it's not you you wrote the SEPA rules, all you did was the sensible thing and pointed them out to the chap.

I've just watched it. I think it's a classic example of how not to self-build. They clearly did sod-all research on the land, so hit high costs with ground works, they've built a medium spec house in a low spec area, never a good idea, as it's almost always the local area that sets the max price. I think they'll be lucky to get their investment back, to be honest, which means they've effectively spent a couple of years doing nothing but spending money in order to gain experience. None of the interior looked particularly "high spec" to me. Laminate flooring, basic veneered doors, painted MDF skirtings and architraves, and what looked like a budget kitchen with laminate worktops. I'd guess it's the sort of finish the majority of new budget builds end up with, and one that will start looking tired within a few years. Even given that it's within London commuting distance, I'm not at all sure that it's worth the £420k they spent on it, given the surrounding area. As they say, house value is all about location, location, location.....................

You can't avoid having to deal with the heat loss, even if you only build to the pretty awful building regs minimum requirements. You will have to meet the SAP requirements, and with large areas of glazing you will probably find that you need to go for the highest window spec you can find and uprate the insulation and airtightness of the whole house in order to get a pass. Might be worth doing some research now, and particularly learning how to drive SAP, You can download a version of the software here, that allows you to play about: https://www.stroma.com/software/sap-software-fsap . Just building to the minimum fabric requirements in the current building regulations Part L1a almost certainly won't now get a pass, whereas in the past it often would. This means trading things like glass area (which will always lose a lot of heat, even with the very best triple glazing available) with the insulation and airtightness of the rest of the house. One mitigation that might work for a house with a lot of glazing like this is to opt to make the house far more airtight than the regulation require as a minimum, then fit Mechanical Ventilation Heat Recovery (MVHR). It's relatively cost effective, can reduce the energy used to heat the house by a large factor (so helps meet the SAP requirement) and gives the added benefit of fresh, clean air in every room, with optional pollen filtering if you happen to have allergies or hay fever. A further advantage is that you can opt to fit an active MVHR, with an internal air-to-air heat pump, that can actively cool the incoming filtered fresh air in hot weather. We've opted for such a system, and it's pretty effective.

FWIW, our pump is still sat inside the foam-lined box that's set into the top of our tank. I've been out working in the garden for the past couple of days and in still moments I can still just hear the pump, pretty much anywhere that end of the garden. It's not loud or annoying, but you are aware of it. It's a bit worse at the moment as the water level in the stream is pretty low, so there's not as much noise from that to mask the hum out. I'm hoping that the small stone box we've built, with it's very thick concrete base (nearly 2 feet on one side, because I had to build up the bank!) will reduce the hum a bit, although the main reason for relocating the pump is just to make it easier to get at to service.

I'm relocating our pump to a small stone box, some distance from the treatment plant, but easier to get at as it's at the side of the drive. The pumps aren't noisy, but they do emit a low frequency hum that carries a fair distance. I'm not sure I'd want it in the house, to be honest, as I'm sure the hum would get on your nerves after a while, even though it is pretty quiet. It's the way low frequency sound like this travels, and is hard to attenuate, that would concern me.

I was thinking that a passive slab would be a very good potential solution, at a lower ground works cost, too. Well worth looking into, in my view. My other thoughts were with controlling heat loss and solar gain. Even if the house is only constructed to our (pretty dire) building regs performance requirements, I think those very large areas of glass are going to need some very careful detailing. These sort of windows worked very well to bring light into cold and draughty Georgian houses, but will be both a significant cause of heat loss in winter and a potentially very significant cause of overheating in summer in a house built to modern standards, unless mitigation measure are put in place. My experience is that few architects are really up to speed with this sort of detail, although those who do a fair bit of commercial work often seem to be.

I did much the same, paid around £250 for a boundary survey, which was useful as the chap included a load of spot heights whilst he was doing it that filled in some of the gaps in the topographic survey we'd inherited with the plot. IIRC I did a web search for local boundary surveyors.

We went with oak linings, stops etc, as I thought it would look a bit odd to have an oiled oak door in a frame that was a different finish. Not cheap though, I think the linings and stops were close to the price of the doors.

Your architect can resolve the issue any legal way he wishes, as long as he makes the decision and takes the action, not you. He may not wish to be the Principal Designer, but no matter what he does the law may well see him as having that role, whether he likes it or not and whether or not he's tried to give the job to someone else. If he's doing the core design work, then by definition it is he that will be considered to be the principal designer, I'm sure. As with the H&S@WA 1974, there is no way to devolve yourself of your own legal responsibilities by trying to pay someone else to take them for you, or to ensure against them. Insurance has no value as you cannot, in the UK, insure against the consequences arising from an illegal act.

The simple answer is to not worry about it, as it isn't your problem, in law. You're a domestic client, and the fact that your contractors (including your architect) refuse to accept these responsibilities is entirely their problem, not yours. They haven't got a leg to stand on if they were legally challenged, but you are fine, you just reiterate that you are a domestic client under CDM2015 and do not have the responsibility, or authority, to appoint anyone into any role, you're simply contracting for a service and expect all those you contract with to act professionally and wholly within the law.

I had a look earlier, but 1/4" BSP or 1/2" BSF were the closest I had - not much use really!

Absolutely essential, in my view, as for us it more than halves our overall heat loss. Mind you, with airtightness that's barely better than the worst allowable under building regs, you probably won't get a massive reduction in heat loss from it, plus you need to make sure there are no nasties, like extractor fans, tumble drier extracts or trickle vents in windows, as they will all defeat the purpose of MVHR. FWIW, our tested airtightness (in the odd UK building regs format) was 1.22 m3/m2/hr @ 50Pa, or 0.43 ACH @50Pa in the more usual measurement system used by everyone else.

I bonded all our oak skirtings and architraves, with no screws of nails anywhere. I used mitre bond for the architrave frames, as suggested above, then bonded them all in place using the water based grip adhesive from Screwfix. Far, far better than the solvent based stuff, as it doesn't skin over and dry anywhere near as quickly. I've not had a problem with any of the 13 doors or any of the skirting - once it's bonded on it stays there. This is the grip adhesive I used: http://www.screwfix.com/p/no-nonsense-11663102-solvent-free-grab-adhesive-white-310ml-12-pack/61428