ProDave

You can't repay it. you could donate it to a charity of your choice if you wish. Well at least it seems for me the government has paid for the cost of my new chainsaw to prepare my "alternative fuel" The Alternative fuel payment was automatically paid to any house in a postcode that does not have mains gas and where the census data says the majority of houses uses something other than electricity as their main heating. I wasn't expecting it but in view of the debacle of the price cap falling but bills rising announcement will gladly spend it for them.

And pencils.

He did not get the tile spacing right, known as the gauging. He should have measured the length of the roof and worked out how many rows of tiles were needed and what gauging (spacing) was needed, and set the battens to that. Instead the second tile down is way too close to the top resulting on only a little bit of tile showing and the knock on effect is the bottom tile does not reach the gutter. Basic error but to correct it the whole lot has to come off, the battens positioned correctly and then the tiles put back. I am not seeing any lead around your half of the chimney like there was before and still is around next doors half of the chimney. That will surely leak. I hope you have not paid his full bill yet?

Try trading standards more like. I assume he has some contact details, this is FRAUD.

With all the pipes cold, run the hot tap collecting it's output in buckets, jugs etc, and measure the amount of cold water that comes through before the hot water arrives. Some plumbers don't understand this issue. I remember refurbishing my first house, my father was the plumber doing it. Installing a new bathroom in the opposite corner of the house to the HW tank. Dad ran 22mm from the tank to the bath tap and then a 15mm branch from that to the basin tap. I argued with him but just could not get him to accept that running a separate 15 or even 10mm from the tank to the basin hot tap, would waste less hot water getting it to the tap.

In Scotland, you have to get a building warrant to build. It's the formal process of building control approving your plans and saying you may start. Equivalent to full plans approval in England and Wales.

Ah so it's not the blind top fitting expansion fitting used on back to wall pans where there is no rear access. So if it is a screw and wing nut, you must get round the back to hold the wing nut still.

That is 3 core and earth but it would do, just ignore one core.

So is the one you linked to but it is also LSF so hard springy insulation.

Low Smoke and Fume cable I think is horrible stuff to work with, the insulation is much more stiff and springy than normal cable. https://www.screwfix.com/c/electrical-lighting/cable/cat8960001?cableproducttype=twin___earth&conductorarea=1_mm_&cm_sp=managedredirect-_-electrical-_-1mmtwinearth

Not all of them do separate from the fixings. But you have straight access to the screw head with the seat down so that is normally not necessary. Your issue is the screw spins, so the threaded insert in the expanding plastic bit is spinning. It is either brute force to pull it out destroying the expanding plastic bit, which you are replacing anyway, or try and apply upwards pressure between the flat metal plate and the pan, e.g with a flat screwdriver, to try and put pressure on the screw as you try and undo it. the main thing is not to damage the pan. This is the price you pay for concealed fittings, brilliant when the work, but a pain when they fail and you can't access the hidden bit that has failed.

Ah so not fixed wiring. A small round flex will do, probably 0.5mm is okay it all depends on the terminals in the light fittings and what size cable they are comfortable with. It's the downlighters that will be the pinch point. Do they actually have terminals for 2 cables to loop through properly? Many don't and you get just one set of terminals to fit 2 cables in, and a cable clamp really only designed to clamp a single cable.

Define what you mean "for lighting" 99% of lighting wiring done by electricians is done with 1mm twin and earth.

The ASHP will only do one LWT at a time, so to do that you would need to run UFH or radiators one at a time, alternating. Is that really going to work better than just keeping the radiators at a low temperature?

Neither am I. In nearly 4 years, I have exported a total of 334kWh which is just the times the inverter generates more than the house uses, even with dumoing to the immersion heater. The point is the DNO are only interested in how much could be exported, not how much will be exported. They take no notice of you actively trying not to export. I will delve into this more after April when it becomes clear how the new system works in practice.

Best not show a picture of a vintage test meter then. Wait until after April. If your test comes out worse than 0.18 ohm, then they will likely say you need a network upgrade. If you applied for that today, there would be a cost. But it looks like after April you may not have to pay for network upgrades. See this thread: I will be watching for how people find this situation after April, I would like more PV myself but don't want to pay for a network upgrade that I don't think I actually need as I have no intention of exporting anything.

A SAP assesment does not tell you the actual heat loss of the building at different temperatures. Be best it does is tell you in the coldest month is uses 976kWh so that's 31kWh per day or an average of 1.3kW continuous. If that is to be believed, the 7kW ASHP should be plenty. Also on that basis, you can probably get enough heat into the house by lowering the flow temperature and running it for longer. That would be the first thing to try and see if it improves the defrosting.

If you want to try yourself, you can get old loop testers for peanuts https://www.ebay.co.uk/sch/i.html?_from=R40&_nkw=loop+tester&_sacat=0&_sop=15 But they will be out of calibration. Question is, what paperwork do the DNO want? Just a figure? or a figure backed up by the instrument serial number and calibration certificate?

Yes this is all pretty normal stuff. This is the period property version of the "plasterboard tent". As you rightly say cold air from the loft fills the void. You should be aiming to fill the top of that gap to the loft all the way round, but it will usually be a miserable job and parts of it particularly in the eaves may be hard to reach.

0.18 ohm loop impedance is a pretty low target. You would have to be quite close to your substation to achieve that. We only achieve 0.24 ohm and rural properties here I have seen as high as 0.4 This is a simple test that any electrician can do for you. The trick with paying someone to do such a short test, is to find someone really really close to your home, or someone prepared to call in on his way to or from another job so you need to be flexible with your availability.

As an experiment, turn off the heating to part of the building, so it is say only heating the UFH part or heating the radiator part, and see if it achieves the target temperature and how much defrosting it does. This might give a clue if trying to generate more heat than it it capable of is the problem.

Where is the hot water tank in relation to the bathrooms? There is a trend for heat pump installers to fit the hot water cylinder right close to where the heat pump pipes enter the house, in many cases a very long way from the point of use. any plumber worth his salt would be advising put the HW cylinder as central as possible to the points of use to minimise the length of pipe and then use thinner pipe like no more than 15mm to minimise the volume of water that must pass through before the hot water arrives at the tap.

I would not do that. Just tell your solicitor what you have and let your solicitor and the buyers solicitor discuss it between them. You then either complete the sale or the buyer withdraws, only then would I take the action you suggest.

Frequency of defrosting is also a function of how hard the ASHP is working. My 5kW LG rarely defrosts when it is just driving the UFH but is much more likely to do so when it starts heating the DHW where the load is higher and the delivered water temperature is higher. Mine is also on the S side of the house where it is always a little warmer. In a still cold winter spell of weather, the north side of the house can remain frozen for days on end, but it only takes a little sun to warm the S side of the house. What may be more relevant from one make to another is how the defrost cycle works. On the LG when it needs to defrost it stops the compressor and fan, reverses the 4 way valve, starts the compressor only which now warms up the evaprorator, and only when it has warmed and melted all the ice, does it start the fan to blow the water vapour out. then it stops and swaps the valve back and returns to normal operation. I am always surprised how quick this happens, and if it happens quickly, it can't be removing much heat from the house. If yours is struggling to reach the demand temperature in the 20 minutes or so between defrosts, it sounds like it is working hard. Could the unit be under sized for the job?

I always board a ceiling first, then the walls, so the edge of the ceiling boards is covered by the wall boards.