Temp

I wonder why they were isolated? I think these work a bit like large expansion vessels. See if water comes out when the precharge valve is opened.

Shouldnt really as rain can splash onto wall above the dpc.

Another with pictures. https://www.pv-magazine.com/2021/09/23/triple-solar-unveils-new-photovoltaic-thermal-panel-for-heat-pump-houses/

Importing is a bit hit and miss at the moment. On arrival in UK you should be charged import duty (which might be zero), UK Vat and probably a handling charge. Only the UK VAT can be reclaimed. That said I've recently imported from China and Italy and paid nothing other than what the seller charged.

They have been sending such letters for at least 14 years as we has virtually the same reply to our full planning application..

If their foundations allow, you could dig a bit deeper, put in a perforated pipe leading to your (or their rainwater?) rainwater drains and cover with gravel. Keep the top of the gravel 2-3 bricks below DPC. If you want to fill the trench higher you would need to tank the side of his garage and then do the above. Personally I wouldn't do this.

https://www.pv-magazine.com/2021/09/21/hybrid-pv-thermal-modules-providing-heat-source-to-brine-water-heat-pumps/ Quote: For two years now, the entrepreneur has no longer heated his home with gas, using instead a brine-water heat pump. That would not be a surprise, as such a system is a standard solution, with the brine being heated up with geothermal energy via a borehole and the heat pump powered with solar energy from the roof. Siegerink, however, did not use a hole in the ground. He developed an attachment that he strapped onto the back of the photovoltaic modules as a heat source for the brine-water cycle. He now produces and sells this solution with his company UseAllEnergy. With this attachment, a heat exchanger, he transforms standard photovoltaic modules into photovoltaic solar thermal (PVT) modules. Such hybrid panels have been around for a long time. However, they couldn’t prevail on a larger scale. One reason for this is that the conversion of a standard PV module would put at risk the manufacturer's guarantee. Another reason is that the water temperatures are not close to the temperatures that pure solar thermal collectors can offer and heat yield is limited to very sunny days. Siegerink was able to solve both problems. Continues..

https://www.fsp-law.com/planning-permission-and-commencement-of-development/ Some councils will tell you what they require you to do. In some cases this is digging foundation trenches, getting them inspected by Building Control and filling them. The problem is that you have to pay a fee to Building Control to get started and some will close a file if progress seems to have stopped. If the council won't tell you then it is possible to do some work and apply for a certificate of lawfulness to determine you have officially started. Wind farm developers sometimes do this while they wait for the grid to be upgraded. Problem is the fee.

We went for 12mm Hardi backer board and would do so again in shower areas. Its hard work to install as its so hard and heavy but our builder recommended it and its bomb proof. I've fixed things like soap dishes and into it and they have remained solid for >10 years.

Welcome to the forum. Can be a bit tricky with clay. An extension that small isn't putting a lot of load on the foundations so that's not really the issue its how the clay may move as it expands and contracts. Probably the best advice is to make them similar to those of your house in terms of depth. Perhaps also line the sides of the trenches with insulation boards before pouring concrete to prevent movement causing an issue. That might well be overkill but its hard to know what you can get away with.

This looks different to the earlier photo. Two switches now on the left? Is there a red wire from one face plate to the other? If so it still looks like Permanant live on Red. Switched lives to the lights on yellow and Blue.

I recal the government are/have consulted on water companies adopting private supply pipes. No idea if that's likely though. You could agree an option to purchase subject to a satisfactory bore hole supply being achieved.

Its common for such things to be in the deeds of all the houses. Not sure if it's possible but it might be worth adding a dispute resolution process. It's not uncommon for one party to want to replace something while another only wants to repair it again and again. Majority voting? Minority pays for surveyors report?

We were going to use hand made bricks but planners rejected them as having too much texture. Ended up using a mix of Audley Antique and another similar brick which I forget the name of.. https://www.travisperkins.co.uk/facing-bricks/traditional-brick-and-stone-facing-brick-audley-antique-pack-of-600/p/621571 Pretty happy with the result and was able to spend more on the roof tiles.

I tried to read up on lime mortar before we built our place but also got differing opinions. Some places say its not real lime mortar if its got any cement in it. Others dissagree. In the end our bricklayers recommended a lime cement mix they had used with our bricks on a garden wall I could go look at. Glad I went with their recommendations. Thus may seem odd but it looks more sandy than cement only mortar. Whatever you decide I recommend you get them to build a sample wall about 1m x 1m using the bricks and mortar mix you propose somewhere in a corner of the site. You can tell them it's to check if the motor mix will look right but also use it as a QA sample.

General idea looks OK to me. This looks a bit higher than the one on the West elevation? Or am I miss reading the drawing.

Our house isn't airtight but we still love our MVHR.

With some WC pans there is space for a block of wood/WBP under the pan. We glued this to the floor and screwed the pan down into that to avoid any risk to the UFH.

+1 to mounted vertically. What I meant was you might be able to run a pipe horizontally then vertically up in the same boxing as the 110m soil pipe and put this small AAV in the loft as well.

Doesn't it just move that drawer space/cupboard from upstairs to downstairs? Or do you loose headroom in the WC?

There are some rules in the building regs about doors opening onto landings. The landing must be a certain size unless it's just a cupboard door.

What reason have they given?

I went with 150mm/6" no rebar. Mine has a tiled roof.

Which way is best depends on the cost of concrete vs bricks and labor, the weather and your attitude to risk.