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JSHarris last won the day on January 9

JSHarris had the most liked content!

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About JSHarris

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    Advanced Member

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  • About Me
    Retired scientist, made the decision to build our own home a few years before retirement, then had the good fortune to be able to retire early and start the self-build journey. Started our build in late 2013, took far longer than anticipated to finish, but have now moved in and we are enjoying having a house with no bills at all (except for the blasted Council Tax...). The house pays us a modest income from the excess energy we generate, over and above the energy we use for heating, cooling, cooking, hot water etc, so we now have a healthy retirement holiday fund.
  • Location
    Wiltshire/Dorset Border

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  1. JSHarris

    Amazing spaces

    I'm just really glad we were able to stay living in our old house whilst building the new one, especially when we went over-budget and the new build ended up being extended by well over a year longer than the original plan. Glad to have got rid of the old place, though, and if doing this again (which we are NOT) I'd question our decision to delay the build as much as we did.
  2. JSHarris

    Is our winter generation amount about right?

    I'm pretty sure that all that is on the MCS chit is the number of panels, the make of the panels and the rated output. I don't think there's anything in there about orientation, so suspect that they wouldn't be able to prove for sure that you'd changed anything. You're allowed to replace damaged panels or an inverter without needing a new FIT application. I doubt very much that the meter reader that comes around would be the slightest bit bothered. Half the time our chaps been around to read the generation meter it's been dark, so he'd never get a look at the panels anyway. If you're worried about the meter reader spotting the change, you could always apply to change your FIT supplier to another company, at the same time as you shift the panels. Chances are you may get a different meter reader who'd be none the wiser as to what the original installation looked like.
  3. JSHarris

    Water Softener: Good Idea?

    I did a few rough calculations about the impact of drinking softened water (I've been on a low sodium diet for years) and concluded that much of what's been written in the past about the apparent risk of drinking softened water is almost certainly scaremongering for most areas in the UK. Harvey have a couple of sections of their website that deal with this, that's worth a read: https://www.harveywatersofteners.co.uk/blog/health-effects-drinking-softened-water and also here: https://www.harveywatersofteners.co.uk/water-softener/faqs/why-it-considered-drinking-softened-water-could-be-detrimental-health . To put this into perspective, it seems important to maintain a balance between sodium intake and potassium intake, from all I've read. If you have a diet that's very low in potassium, or have a water supply that is very hard, then there may be a slightly elevated risk. I asked some questions as to whether it was OK to use softened water in our boiling water tap (an Itho, which isn't sold under that label in the UK any more) and at first was told that it wasn't OK. I then tracked down the original manufacturer of the softening filter and obtained the specification for it from them (not easy, the thing had been re-badged twice). What I found was that the softening cartridge filter that was supplied with the tap was in fact a sodium ion exchange resin cartridge that was pre-charged with sodium, so was giving out softened water that was much the same as that which comes out of our ion exchange softener (which is a Harvey unit). I went back to the tap manufacturer and asked again about using softened water, highlighting that the specification of the softening filter they supplied with the installation kit was actually a ordinary sodium ion exchange resin unit, and they wrote back saying that there was no problem using softened water with their tap at all. I was left with the feeling that their original insistence on using their (very expensive to replace) filter, and not connecting a softened water supply directly to the tap was probably a marketing ruse so that customers would feel obliged to carrying on buying very expensive, custom branded, replacement softening filters from them every six months. As far as taste goes, then I find that tea made with softened water and the boiling water tap tastes better, and doesn't have the nasty scum, than tea made using a kettle and our local fairly hard water. I suppose it's a matter of taste, but we lived in Cornwall for many years, then South West Scotland for a few years, so we're very used to the taste of tea made with very soft water, and found the taste of the hard water when we moved down here pretty unpleasant.
  4. JSHarris

    Being on TV

    We went about £18k over budget in terms of cash spend, and probably another £20k over from all the labour I put in, because we hadn't got the money to pay tradespeople to do the work (which wasn't part of the original plan). Overall we probably went about £38k over budget, allowing for the value of my labour. The problem with going over budget when you just don't have the money is that it really does drag out the build for a long time, which then ends up increasing your costs even more, just from things like insurance, travel to and from the site, and even council tax towards the end, when you can't put off having to pay it any longer. It's a bit of a vicious circle, and looking back I think I'd have been better just trying to find a way to borrow some more money to fund the build and probably finish it at least a year or so sooner. We'd have then been able to sell our old house earlier, to pay of any loan and replenish our savings, as well as having saved a year or so's worth of council tax, insurance, travel costs etc, which probably added up to a wasted £3.5k or so, all told.
  5. JSHarris

    Is our winter generation amount about right?

    TBH, I was surprised when I looked at the daily total, as based on the generation until about lunchtime I was expecting we'd get around 12 kWh. Today looks like it might be another good day. Cold last night but bright this morning, with just a bit of light high cloud. Nice to start generating again in earnest, as December was pretty dire.
  6. JSHarris

    Preliminary plans have arrived

    It's really a DHW device, but that's all that's needed for a passive house, as heating really isn't an issue worth investing serious money in, as the requirement is so low. The Sunamp can provide DHW at around 58 deg C from a relatively small box, that can be heated up by excess PV generation if available, or boosted by E7 for two or three hours overnight if needed. We've been guinea pigs for the technology for around three years, and recently installed their latest model, which is simpler and has about double the heat storage capacity, but I have to add that it is still a work in progress, and the control system needs a bit of refinement. However, Sunamp are supposedly developing a new control system that may address some of the irritating failings of the current system, and once that is available the unit should be very good indeed. For heating, it's dead easy with a passive house to just fit UFH inside the ground floor insulated slab and use that as a massive storage heater. Charging this up at night, using E7, works very well, and is now how we run ours. We have a programmer to enable the UFH charging during the E7 period and a room stat that determines whether or not the UFH actually turns on and heats the slab. Some days in winter the slab doesn't need any heat (it's not heated up at all for the past two nights, and may well not heat up tonight, either), other days it does, and once warmed up it slowly releases heat into the house for the next day or two.
  7. JSHarris

    Preliminary plans have arrived

    Very much better value to go for PV panels, as you can use the energy generated for pretty much any purpose, they cost far less to install (in terms of cost per kWp), have no maintenance requirements etc. We originally fitted a thermal store, but found that the heat losses from it made the services room far too hot (over 40 deg C) and cracked an oak door, as well as making the adjacent bedroom too hot in summer. I removed the thermal store and replaced it with an electrically heated Sunamp phase change thermal battery, that works like a combi boiler, and instantly heats hot water. It's not perfect, and Sunamp need to refine the control system, but it's massively more efficient than the thermal store. Today, for example, our in-roof PV array had fully charged the 9 kWh capacity Sunamp by around 11:00, and I could have used the excess PV generation for the next few hours to charge my car, if it wasn't already charged up.
  8. JSHarris

    Gas nailer servicing

    I know this may be contentious, but just get an air nailer. All I've ever done with mine is put some fresh oil in the in-line oiler. It's never, ever, jammed, never needed any maintenance and just works every time, with zero misfires. Judging from all the Paslode nails I picked up (or rather the young labourer did) I'd have to say that nothing would convince me to own a gas nailer. Not only is the air nailer far more reliable, and needs next to no servicing, but it was also a heck of a lot cheaper to buy than a gas nailer. Friends in the US can't get their heads around the UK's obsession with not using air tools when frame building.
  9. JSHarris

    Noisy pull cord in bathroom

    Not great when you have a wife who gets up, half asleep, a couple of times a night and REALLY, REALLY does NOT want to have the glare of the bathroom light coming on.... (BTW, the solution for that particular problem has been to fit a very dim, single LED light, set near floor level, that is switched by a PIR. This allows navigation without creating high levels of grumpiness for the following 24 hours...)
  10. JSHarris

    Noisy pull cord in bathroom

    We had the same problem, and I have found a pull switch that is much, much quieter than any other one I've heard. It just makes a gentle, single click, not the loud double click that most make. I've changed our switches for just this reason, they were too damned loud. These are the ones, from TLC: https://www.tlc-direct.co.uk/Products/CM2781.html
  11. JSHarris

    Preliminary plans have arrived

    I've looked at spraying the house to try and control cluster flies, but it apparently does more harm than good. It seems that wasps feed on cluster flies and insecticide tends to kill the wasps which then removes a natural predator and tends to make the next generation of cluster flies more prolific. If someone has a foolproof method for controlling cluster flies then I'd really like to hear about it, as I've yet to find anything that works really well at either controlling them, or just dissuading them from swarming around our house at certain times of the year.
  12. JSHarris

    Preliminary plans have arrived

    We just have UFH, with the pipes cast into the passive slab foundation, so only on the ground floor. Our absolutely worst case heating requirement, with everything in the house turned off except the heating and MVHR, no occupants, a set room temperature of 21 deg C and an outside air temperature of -10 deg C, is 1,600 W, though. In practice the house never really needs more than about 500 W at the most, though, as with a couple of hundred watts of incidental gain from appliances etc, another couple of hundred watts from occupants and an outside air temperature in winter that averages at around 4 to 6 deg C, the house doesn't really need much in the way of heating at all. We run the UFH from an ASHP, but that's not cost effective, as we will never recover the capital cost of the thing from the electricity it saves (we are all-electric, no mains gas here). If we wanted the best value heating system then that would be to fit a WIllis immersion heater inline with the UFH and pump, and just use the ground floor slab as a storage heater. Run from E7 it would only cost slightly more to run than the ASHP, and has the advantage that the capital cost would only be a couple of hundred pounds, rather than a couple of thousand for the ASHP (that difference would buy enough electricity for a decade or so of winter heating). We have no other heating, other than electric towel rails in the bathrooms that are automatically switched on and off in the morning and evening on a time switch controlled circuit (plus they have their own switches to disable them if they aren't in use). In theory we could heat the house using the Genvex MVHR, just as we use it for comfort cooling, but in practice neither of us like the slightly dry air that warm air heating tends to give. This is very much a personal preference thing though, as @PeterStarck uses his Genvex MVHR as their main form of heating and they are very happy with it. We had an open weekend a couple of years ago, where we we had around 60 people visit the house over two days, in groups of three or four, for an hour or so each. One couple had just completed a passive house build and had chosen to fit a tiny wood burning stove (a room sealed one, intended for use in canal boats I believe). I think this was one of the very lowest output units that was available, around 2 to 3 kW IIRC. They related their experience with it, when they lit it for the first time on the previous Christmas Day, when they had family around. Apparently the living room quickly warmed up to well over 30 deg C, and even with all the windows open it was too hot, so they evacuated the room, shut the door and left it with the windows open until the fire died down and the room cooled (which was the following day, apparently). When they visited our house they mentioned that they were in the process of getting the flue and air supply duct blocked off and having an LCD screen fitted behind the front of the stove to display a flame effect. If you want real flames and a low heat output, then a bioethanol stove or fire might be worth looking at. They don't give out much heat, don't normally need either a flue or an air supply (so good for airtightness) but they can be a bit expensive to run, if you use it a lot. As a feature, that's only used occasionally, I think they are probably a good compromise for those that really want to have the look of open flames in a room in a passive house.
  13. JSHarris

    Preliminary plans have arrived

    I take your point, but assume that you aren't plagued with cluster flies! This is the second house we've owned which has been a magnet for the damned things, and we've learned over the years that there isn't anything much you can do about them, other than not open windows and open and close outside doors as quickly as possible when going in or out during cluster fly swarm periods. From all I've read up on cluster flies over the years, I've not seen anything that's a reliable predictor as to whether or not a given house will attract them. Our neighbour on one side never has a problem with them, the neighbour the other side has much the same problem as we do. Once they decide they like a house they will keep coming back, pretty much no matter what you try to do to dissuade them. This leads me to believe that relying on having to open windows to get ventilation at the design stage may not be wise, as there is no way of telling at that point whether or not the house is going to be a "cluster fly magnet", other than, perhaps, if it's in the middle of a large town or city, where the damned things don't seem to be a problem.
  14. We had fifteen planning conditions, with four of them being pre-commencement and two of them being mutually exclusive, which resulted in the planning officer over-ruling one of the conditions he'd imposed (I don't think he'd actually read the two conditions together and realised that both couldn't be met!).
  15. JSHarris

    Preliminary plans have arrived

    But why have to open windows, letting in bugs, unfiltered air, etc, when the MVHR can just do it with no reduction in air quality or need for any form of intervention? We do have opening windows in every room, but never bother to open them. One reason is that we're in the countryside and plagued by cluster flies whenever the sun warms up the outside of the house, so the last thing I'd want to do is open a window and have a house full of flies within a few minutes. The cluster fly problem goes away by late spring, but then so does the overheating problem. Sadly the cluster flies come back in autumn, just when the house is prone to occasional overheating again.