ProDave

I am pretty sure that's 3 phase, neutral and earth 240V so "Low Voltage" in DNO speak. I don't know if that changes how close you can build to it or not? but will still affect materials unloading and if you need a crane etc. I am not sure from the plan you posted earlier which is new and which is existing buildings, and how far from the pole they are?

I think the filter is inside the ASHP perhaps if there is anyone that knows this model could comment. Is is still in warranty? Can you play on the fact you have no heating in this freezing weather to get them to come on an emergency call?

That is exactly what we do. I don't see the need for a fancy complicated control panel.

Can you confirm it works normally in space heating mode, i.e. the pump continues to run and the house is warm, and your problem is only when trying to heat the hot water tank?

First turn the heating off completely so all pumps stop, and confirm the flow meters all return to 0. It is not unknown for them to stick. Any change you make to flow rate by rotating the flow meters should register immediately.

Assuming the inverter is not mounted right next to your electricity meter, then all he is meaning is you have to get a cable from wherever the inverter is, to your incoming supply point to get that current clamp onto the supply cable. He does not literally mean the cable connects to the smart meter, but the the current clamp that is in the vicinity of the smart meter.

The driver would be responsible. You may have issues with delivery drivers refusing to operate a hiab unless then can pull completely off the road onto your land so they are far enough from the cables for the hiab not to reach them. And in any event if you are building within 10 metres of the cables, you will have issues and I think under 6 metres is a definate no (it was when I enquired)

the 4 speeds are selected by 4 volt free contacts. You could buy a switch that could be mounted anywhere in the house that was simply a rotary switch labelled 1,2,3,4 but I chose to do my own thing. I used this sort of time switch But because that has a switched 240V output I use that to switch on a small relay, that then provides the volt free contact to connect to the ASHP

Is this to divide it into a pair of semi's?

In Scotland, you have to submit full plans, there is no simple building notice option. Building control approve the plans before you can start and then their inspections are to determine it has been built according to the plans. If something changes, and they deem it important (I would expect such a massive change in the insulation spec to be so) they will insist on a new set of drawings to show the changes. As this is an extension, it might be being built under a building notice where it is everything agreed as you go. but as the client I would want to be involved in any discussions changing anything.

Thanks, glad you got it fixed.

I am so sad for you, this is a shocking example of shocking builders both for not following the plans and not even discussing with you when they want to change something. Ditto building control. WHO appointed building control, you or your architect? Is your architect involves still and supposed to be supervising this? Who appointed the brickie and joiner? you or the architect and under what terms where they appointed? You need to understand the chain of command here before you can decide who is at fault and what action to take. I would certainly STOP any further work until a resolution plan is agreed. Is the outer covering of the flat roof on already? This is why I project managed my own build and watched like a hawk everything that was done, but thankfully I had appointed builders I knew and trusted and they discussed any changes before implementing them, and they were mostly changes for the good.

I suspect the stay will have to stay. If I am understanding your pictures, the stay is perpendicular to the road, so putting your entrance to one side of the pole, it will not be blocking the entrance. To prevent people walking into it, I would plant a row of shrubs / bushes directly underneath it and let them grow high enough and the stay will be hidden, embeded in the greenery.

Is it a single 3 way valve or multiple 2 way valves. Either way it sounds like the valve to the hot water tank not opening so there is not enough flow. that could be a faulty actuator head or it could be a mechanical fault (seized) If you don't know, post a picture of the HW tank and all valves or controls on or near it.

Have you paid him? If not don't. I would be having serious words along the lines "you did not build what you were contracted to build and what was shown on the approved drawings. Correct it to make it match the approved design AT YOUR EXPENSE" If I need to change something when I am doing a job, I discuss it first with the customer.

They certainly don't seem to understand safe zones.........

About 4 years with no issues. The problem was my MVHR unit only has 4 speeds (it actually has a fine +/- adjustment on each speed) and I needed speed 2 to get the BR rates in all rooms. At that speed it was just audible in some rooms. So now it runs at speed 1 with the + adjustment on. It's not much below regs levels but dead silent.

WHY? Seriously I would sack the joiner, he knows nothing about buildings. If you had followed the plans you would have a warm roof that does not need ventilating and you would not have these issues. Just why did he want to go back to "the old ways"? No wonder the building trade is so poor in general. Sorry a bit of a rant, but there are plenty of people having issues with their homes in this cold weather, and your joiner talking you out of doing it properly is an example of why.

If you want to do it better, you have 175mm joists, fit 100mm insulation boards with a 25mm gap between the top of the insulation and the cold deck, that will leave the bottom of the boards 50mm above the bottom of the joists. Seal (tape) all the joints no gaps no holes. Put all the wiring on the underside of the insulation. If your downlights are more than 60mm deep, batten the underside of the joists with 25mm battens to drop the ceiling to then give you 75mm from the plasterboard to the insulation to fit the downlights.

With no plasterboard and that great big gap, the warm moist air from the room can get to the cold deck board and it is no wonder you are getting condensation and mould. The insulation might as well not be there at all for all the good it is doing. Really bad design, I would not use flush downlights without a re design of the roof personally. The best you can do is fill in as much of the gap as you can leaving just a very small round hole for each light, and then fit a sealed downlight, NOT the open framed ones to try and minimise how much of your precious warm air can escape to the cold side.

Can you post a picture further out to give more context of what we are looking at there. Where are the lights? indeed where is even the ceiling plasterboard? How are you seeing this or is it not yet finished and the plasterboard is not yet on?

That is not where the pipe fits, that is where the trap screws on, it is not intended to take a pipe int there. the outlet of a trap is a compression fitting with a rubber seal with enough flex to accommodate the different sizes of "40mm" pipes

I always encourage my customers of a new build to buy the materials themself and I just give them a shopping list.

Just buy it, it will fit, in the UK there are really only 2 sizes, bath and basin. You would be very unlucky of you had a non UK bath waste and trap fitted. UK waste pipe sizes annoy me, just look at how many different sized "40mm" pipes there are available. but at least the screw thread fittings for wastes and traps is pretty standard.

Not meant to be serious: Turn gas off. Drill hole. Turn gas on. Can you smell gas from the hole? If you can you know where the pipe is and where to repair it. If not, you missed the pipe. Hang the cupboard. For a final sanity check, get a gas safe engineer to do a drop test, just in case you grazed it and made a minute hole.