ProDave

That is an old and very common way of bracing the joists to stop them twisting. More commonly done with solid noggins now. Why not replace with solid noggins with large round holes drilled in them for the mvhr ducts to pass through?

Comfort in use is largely a case of what you are used to. The going of our stairs is a lot more than the minimum. I can get my size 9's flat on the stairs entirely on the stair. Contrast that to many older houses, built before modern building regs where the going of the very short stairs is only about 3/4 the length of my foot. That now seems an insane design to me, but as a younger man used to stairs like that, I thought nothing of it.

Our house is 7M deep so only a bit more than yours and especially if you are having room in roof or 1.5 storey, as you say you may get into head height issues. For this sort of house a stair split into 2 with a half landing works well. In our case up 6 stairs to the half landing, turn 180 degrees and up another 7 stairs and you arrive on the upstairs landing at almost the highest point of the roof structure and no worries whatsoever about head height. I then took the available space we had, constrained by doorways downstairs and upstairs, and made the going as long as it could possibly be and I think we arrived at about 40 degrees. All easy to do with the Stairbox on line tools and that is who supplied ours. The challenge will be to design a two flight stair as a floating stair, I leave that for someone with more imagination than me.

You need to make the place a bit more upmarket. A new mirror will help them see what they are doing. I have found just the one.

Link gives me 502 Bad Gateway.

One more reason not to be a LL.

Get a quote for the electricity supply, then you will know for certain where it actually has to connect to. Then see if once you have accepted the quote they can issue the cable for you to bury in the field. It does not have to be in duct is is usually suitable for direct burying. If you do go for duct, put large diameter twin wall flexible with gentle bends, don't put elbows. Then never contemplate using the provided drawstring, use that just to pull through a larger bit of rope as your drawstring.

When I was building my house, I too did not believe it would require so little heat. So I did a test. Once the building was complete, insulated and all windows in I put a simple electric convector heater on 24/7 in the middle of the downstairs, for a week, and took daily internal and external temperature measurements, and confirmed the difference was in line with what you would expect with that much heat input thus proving Jeremy's spreadsheet was bang on. I then had the confidence to buy a heat pump.

-10 IS realistic as an outside temperature up here but not for many places in the UK. Bet even at -10 my heat loss was about 2.5kW so a 5kW ashp, about the smallest you can buy, would only spend half it's time heating the house, so plenty of time to heat the DHW.

This ASHP is about 10 years old, well outside guarantee and this is the first time there has been a failure.

I was back today. I confirmed the 300V dc and 15V dc supplies to the motor are present, and when the compressor starts, the other 2 (exact function not determined) connections have variable voltages present. One will be the speed demand. So the motor is dead. The list price appears to be just over £400 plus VAT plus postage. That is a criminally high price in my opinion. Anyway I found one listed on ebay for £200 so that has been bought an on it's way.

For what it is worth, I previously owned a property in a similar situation. I briefly thought about trying for permission for a separate dwelling, but soon concluded, even if it was possible, it would leave the original small house with little garden, the new house would also have a tiny garden, and they would have to share the same road entrance and parking making it even more awkward. I ended up instead extending the original house making it nearly double the size and that met with no opposition and was a better use of the space.

There is a "building" shown in the corner of the existing plot. Is that a garage for the existing house built right up to the road? If so that will be in your favour as the building line and visibility is already breached. Where will the existing house park? I expect both would have to share the same entrance as I doubt a new one would be allowed closer to the corner. Make an offer "subject to planning" and submit a planning in principle application. If that is rejected you can walk away with little cost. A suitably anonymised streetview screen grab might help.

I would question what that meter is actually reading and is it true? for a sanity check, I would read the dial on your electricity meter (not any in home display if you have a smart meter). If you know the time of the sterilisation cycle you can read your meter before and after the cycle and see how much electricity it is really using. Try and not use any other big loads in the house during that time to get an accurate reading.

My plumber up the road called me today. His Mitsubishi ASHP has stopped working. Model number PUHZ-W85VHA2 Symptoms. It just does not work. No errors shown on the in house display panel. Went outside took the cover off the control panel on the outside unit. Gave it a heat demand and watched. After a short while the compressor started, but the fan motor did not start. After a minute or so the compressor stopped and the on board 2 digit 7 segment LED display showed the code U8 which means fan failure. The fain looks very similar but not identical to my fan motor in my LG ASHP. It has an inbuilt variable speed controller. It is supplied with 320V dc (rectified 230V ac) and has a few low voltage control inputs. Unlike my motor, it does not identify on the label what wire does what. So testing today was somewhat limited, other to confirm the 320V dc is pesent. The motor has the part number RG61V143H35 on it. What I have done so far: I have found the service manual, it can be downloaded here https://www.manualslib.com/manual/769585/Mitsubishi-Electric-Puhz-W85vha2.html#manual And the Mitsubishi parts list is here http://www.mitsubishitech.co.uk/Data/Ecodan/Air/Monoblock/Outdoor/PUHZ-W/2012/PUHZ-W85VHA2_SP_OCB465A.pdf From that I have determined the Mitsubishi part number for this fan motor is S70E10763 Next steps: The service manual tells you how to check the 320V and 15V supplies to the motor, so I will go back and do that. There are no test points on the control pcb and the connector does not lend itself to meter probes, so I will splice some test points into the motor lead before going back to do more tests. The only 2 fault conditions identified in the service manual are faulty motor - replace (list price about £400) or replace control PCB (no idea how much that would be) I think the chance of repairing the motor is nill, as far as I can tell all the electronics inside the motor are encapsulated in a plastic moulding. More to come I am sure.....

All scaffold will wobble and risk falling over if you push it to extremes. I bought a load of Kwikstage when building my house, and when I sold it, I kept enough to scaffold one wall of my house. the scaffold lives on a rack in my garden and the boards are stored dry in a custom made enclosure under a raised decking area outside the back door. Much more heavy and needs 2 to assemble it compared to a lightweight tower. But even that needs some bracing at height. You can see in this picture scaffold up the gable wall and the square frame sticking out towards you in this photograph exists just to give it some more bracing.

Is the 2 port normally open or normally closed? Is there any other source of heat e.g. a stove?

Most convert the 50Hz ac to variable frequency ac to power the compressor. I take it you are trying to get something working off grid with PV and dc batteries? Try looking at units made for caravans?

One of the panes is cracked and that has allowed moisture to get between the panes. The glass unit needs replacing.

Build the footings either side of the channel, and bridge the gap over the channel with reinforced concrete lintels. Build wall off the lintels. Why make it difficult?

I assume these are let as separate units or a hmo? It would be most unusual to have 2 separate flats sharing one supply. Who pays the bill? let alone a third unit sharing the same supply. Now you want to add a 4th. Forget lighting. It is the big loads that add up. If you are serious about this I would first shift everything that can be to gas. So gas hobs, gas water heating and showers running from gas HW. Then you are only looking at other stuff on the limited electricity supply. Why are you not doing this properly and getting a separate supply to each unit?

The point about electric panel heaters in bedrooms, is a well insulated air tight house with mvhr most of us find does not need any heating at all in the bedrooms, even up here in the Highlands. But a lot of people are not comfortable with no heating so installing electric points for panel heaters just in case you find you do need some bedroom heating, is a comfort blanket and cheaper to install a few cables that never get used, than a whole lot of upstairs UFH pipes that never get used. If you think you want upstairs cooling look at fan coil units that normally go in the ceiling and will do heating and cooling. The cost of them has put me off and so far we have only had one spell of weather when I might have liked them for cooling. Re the grant. I bought all the parts and installed my own ASHP for WAY less than £7.5K. You only have to look at posts on here on the subject of heat pumps and grants to see it does not seem to work in the customers favour. You might naively think the installer would charge a fair price for the materials and a fair price to install them, then deduct £7.5K leaving the customer with a very small or even zero bill. Sorry to say that optimism will soon be dashed when you start getting real quotes and one is left wondering how can they charge that much?

Actually I don't think that is the OV10 vent there, that is a mock up when working out how to do it. The builders fitted the counter battens not me, they cut them that length. Yes vent fixed through membrane and tray

This is what I did in a similar situation Eaves tray on first. Membrane lapped over eaves tray Counter battens than battens. OV10 over fascia vent on next Then tiles, bottom tile resting on OV10 vent. The OV10 vent is made for this job, it is in line, most other vents tend to "turn a corner" so the outlet would face downwards.

Don't throw it away. Easy repair. I was given 2 by a joiner, both "worn out" and replaced for free by Makita under guarantee. In both cases it was the front bearing of the motor that had worn out. I bought 2 replacement motors for about £20 each from ebay. Mine is still going strong, the other went back to it's original owner.