ProDave

I used dry screed often called pug mix. On top of joists lay OSB or ply, 25mm battens following joists, lay UFH pipes then dry screed, final floor (engineered Oak) on top. Very easy to DIY. Don't forget to include extra dead load when calculating joist sizes.

You used to be able to download the SAP program and input all the details yourself. You could never produce an officially recognised EPC doing that but it is a good way to while away a lot of time. For a good EPC you need good levels of insulation, good probably triple glazed windows, good air tightness that probably means a proper air tight membrane everywhere with well taped joints and good detail at every penetration, An efficient heating system, probably ASHP and UFH, MVHR and possibly some solar PV. and an official air tightness test. When I sent all the final as built figures to my assessor, my instructions to him were that if it failed to get an EPC A, to not lodge the EPC instead come back and discuss what would be needed to achieve an A. It came back with an A94 which I was happy with.

One issue I see is there might be a "warm up time"? If the heater is only a few kW then first time you turn it on, the shower temperature will be low as the waste temperature is low. Once warm waste water starts to reach the unit the flow temperature will warm up, but would there be an issue with a tiled shower where the waste water would initially be cooled by the cold tiles and may be a slow warm up time? Happy to hear how it works in practice. It sounds a good idea but only of interest to new builds or a serious bathroom refit. The biggest market would just be to replace existing electric showers, but the piping for the waste means that is not possible. How do you deal with access for servicing the unit? It seems like it needs to be under a floor with an access hatch to reach it. That might work with a carpeted landing next to a bathroom where you could fold back the carpet to get to a hatch?

In what way is your heater more efficient than others, how does it heat the water?

No problem at all, standard practice when wiring industrial cabinets.

I am electric only and remained on the variable tariff. The only fix they have offered me for a couple of years would have only been a tiny saving and as we keep hearing the price cap will fall over the summer, it was unlikely the fix would save money.

Voltage drop is going to be your issue. Voltage drop for 10mm is 4.7mV / Amp / Metre So at 16A and 60 metres that's 4.5V drop. That is per core, so total volt drop = 9V That mainifests itself as voltage rise when the inverter is generating. Most inverters will shut down or power limit at 253 volts. So with that much volt rise, if your house voltage exceeds 244V your inverter is likely to either shut down or reduce power. I would first measure your typical mains voltage and see how close you are . With long runs it is better to do a large part of the run in DC cables with the inverter close to the house. Volt drop on the dc side does not usually cause any issues.

What does this "4 pipe" system do to improve efficiency? My ASHP is only 2 pipe (as I think they all are) and it only ever does DHW or Heating (with priority DHW) and runs both at different temperatures. It can be plumbed with a 3 port 2 position valve (not mid position) or as I have, with individual 2 port valves. The only disadvantage of the 2 pipe I can see is when it switched from DHW to heating, there can be a slug of water in the pipe at DHW temperature sent to the UFH (but the mixing valve on the manifold stops that being a problem) I fail to see what magic improvement a 4 pipe system can bring and why a heat only 2 pipe boiler cannot be set up to only do DHW or heating with priority DHW. That is more how you wire the controls than how you plumb it (as long as you avoid using a 3 port mid position valve)

I would at least try to get permission for another gable end window like the one in the master bedroom. Tell them it ia a building regulations requirement. If they say no,take it to appeal on the same grounds.

In an ideal world, you would have those valves (supplied with the manifold) as in the top picture, AND another set of valves, installer supplied under the pump. Then if you need to change the pump you can turn them all off and swap the pump with almost no loss of water and minimal bleeding. Operation should not differ between the 2 options.

The reason we didn't do that is 2 coats of Osmo oil each side a day apart and 2 days to dry before you can turn the door over to do the other side = a week per door. You either need a lot of space and a lot of tressles (which we didn't have) or a lot of time to do them sequentially. Obviously painting them flat means no chance of drips.

Get a 32A commando socket fitted in your temporary power box and plug it into that.

We did ours after hanging. We used Osmo door oil.

That was my original design bodge, when I realised my LG ASHP had no "correct" way to turn HW on and off from an external device.

Yes, definitely fell the trees you want gone ASAP in one go as quick as you can. You don't want someone slapping a TPO on them if they get a hint you want to build, so don't give any warning, just turn up one day with a chainsaw(s) and get felling.

L shaped bracket, screwed to the newel post, handrail sits down onto it and you screw into the bottom of the handrail through the bracket. You will need to rebate the end of the handrail to accommodate the thickness of the bracket. I would do that anyway, I would not want a screw head through the newel post to plug or otherwise hide.

Clearly prices are higher on Skye than here. A couple on min wage would earn £43347 and a mortgage 3 times that gets them £130K then add a 10% deposit gets them to £144K they can spend on a house. Plug that into a search on hspc.co.uk and I counted at least 50 properties they could buy. That is way easier than when I bought my first house down south, where even earning considerably more that a basic wage, I had to borrow a higher salary multiple with a higher deposit and I struggled to find anything and I literally bought the cheapest property for sale in the county, and then struggled to pay for it for the first couple of years. There are not loads more small cheap houses for sale, because it is impossible to build them cheap enough. I don't think planning is an issue, as long as you propose building within an existing settlement, it seems quite easy to get planning here even in the countryside.

I don't know what OS you have, but if you save the file just about any file manager will show you the file size, unless you have everything set to just show you a little icon of the picture rather than proper details.

I find a 10kW shower woefully inadequate, that is based on showering with an electric instant electric shower, and the 10kW instant gas water heater we had in the static caravan. So I would guess for a proper decent shower you are looking at 25kW or more? I think the 10kW shower was rated at less than 5 litres per minute. I can get almost 15 litres per minute from an UVC fed shower.

Try as an alternative, get your image on the screen of your computer and take a screen shot and save it, then post that here. What does your file manager say about the size of the image you tried posting that came out tiny?

I just used a simple emitter follower to connect an I/O pin of the Arduino to a 5V solid state relay.

Why is it inefficient? The boiler would be working hard to re heat the tank as quick as it can, not short cycling and would shut off as soon as the tank reaches temperature. Yes the more times it does that it has to re heat the water within it and the water in the connecting pipes but that is a small volume. Mut unike room thermostats, a tank thermostat usually has quite a large hysteresis, so it would not be firing up to re heat just because the tank has lost 1 degree of water temperature.

Some random thoughts from how I see it, yes as an "incomer" House prices here are too cheap. That is to say is is almost impossible to buy a plot, build a house and then sell it for what it has cost. e.g what we eventually sold our 5 bedroom house for was not a lot more than it cost to build our new 3 bedroom house, and if we had persisted with selling it 8 years ago when the market was moribund we would probably have needed to drop the price to the point the 5 bedroom house would have sold for less than the build cost of the new 3 bedroom house. While we could sell our 3 bedroom house now for a little over the build cost, we would then not be able to build another 3 bedroom house for that money as material costs have gone up so much. Coming from the south, it is laughable to hear the talk here of "affordable housing" There are plenty of houses at the lower end of the market that a couple on minimum wage should be able to buy comfortably. It is not house prices or affordability that drive youngsters to the city. They simply find rural life too boring. I don't think it will be long before our daughter leaves home and the city is where she wants to be. I am completely the opposite, having been brought up as a child in a city, I could not wait to get out to the countryside and have no desire to go back. I don't know how you solve that one. IF we did go ahead with this holiday let plan, and at the moment it is looking very unlikely, we would be wanting to employ the services of somebody local to look after it. I still don't know if that would be something easy to find or it we would be shunned and nobody would be interested? It is the burden of regulations that is putting me off mostly, and threat (likelyhood) of more like "tourist tax" that worries me. But also the property market is very skewed here, almost compressed. Having just sold a 5 bedroom house we would like to have bought a 2 bedroom house for a lot less, but what I am finding is the one we are considering is only 1 bedroom, and on the market for half what we got for the 5 bedroom house. That to me is just way too much.

Which is why a short pipe from the well head to a close by power station makes sense rather than a massive, distribution network to individual homes.

Normally an UVC will start off full of hot water heated to the set temperature. As it is used, a hot / cold transition moves up the tank. If no more heat was added, you would get almost the same temperature of water coming out of the taps right up to the point where the hot / cold transition reaches the top of the tank and the water would suddenly go very cold. If the cylinder thermostat was say half way up, then at the point the transition reaches the thermostat the boiler would fire up. At that point the heat input to the tank would stir up convection within the tank and continue to do so while it is heating. With the heat source being a big boiler, it can probably re heat the tank as fast as you can empty it.