Temp

Is that 3 x 7KW chargers = 21kW = 90 A ? 12kW ASHP with COP of 3ish would be about 15A

Planning Permission and Building Control Approval are two different things. The 15sqm issue is normally a Building Regs issue rather than Planning Permission issue. I don't think there a limit on floor area for planning other than: A) it must not use more than half the area of the original garden. B) it must be what they call incidental to the original house. Eg not so big its virtually dominating the house or capable of being a dwelling in it's own right. I don't think either are likely to be a problem for you. I believe you can buildi bigger than 15sqm under permitted development. However there are limits on eaves and ridge heights under permitted development and this can be an issue if you want a pitched roof or lots of insulation. The bigger the footprint the lower the roof pitch works out. If you want decent insulation the eaves height limit for buildings near the boundary might be an issue. Eg a 2.5m high roof with 300mm of insulation gives a ceiling height of 2.2m which is a bit low. Less 8f the floor is above ground level. Perhaps keep it away from the boundary so the eaves height can be higher? 0 As for Building Control Approval.. https://www.planningportal.co.uk/permission/common-projects/outbuildings/is-building-regulations-approval-needed-for-an-outbuilding So you will need Building Control Aporoval if its going to have a bedroom. Also because it has drains.

I got one of these for indoor use. https://www.amazon.co.uk/gp/product/B092HXDGS3/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Works for me but I've got nothing to compare with. Frequently you want the laser to draw a line through an existing mark. Say a vertical line. It can be fiddly to do that because small movements of the laser level translate to large movements of the line on the wall. A tripod with a knob you turn to rotate the level might solve that. Also needs a way to raise and lower the unit to adjust the height of horizontal lines smoothly. Otherwise you need a lot of different thickness blocks of wood etc.

I met our builder while his bricklayers were building a massive garden wall around a barn conversion. They also said they prefer to use lime in the mix but I don't know if its proper lime mortar (I doubt it) or if they just add lime to a portland cement mortar (which some frown upon). Either way very pleased with the result. They used a section of 1" dowel to strike the portar so not pointed separately.

Take a look at the rules on "Permitted Development". You may not need planning permission. However the rules are moderately complex. If in doubt post details here of the dimensions and we can comment. The building shouldn't be too self contained. Eg if you put a kitchen in it as well as a bathroom the planners might object.

Either way I would get a 1m X 1m test panel built to see what it looks like and for quality control.

Previous thread on windows in corrugated roof might be worth a read.. https://forum.buildhub.org.uk/topic/8984-corrugated-metal-roofing/

Perhaps you could hammer in sheet piling as used to protect workers in deep holes? Not very pretty but you could clad it with something, even just regular fence panels?

Check the flow pipe temperature. Might be set to 72 but is it producing that.

When it's struggling to achieve the set temperature does the boiler run continuously or cycle on and off?

https://www.northantstelegraph.co.uk/business/construction-starts-on-corby-site-which-will-be-europes-largest-modular-housing-facility-4000305

Lots of suggestions but what actually is SWMBO unhappy about? If she's cold it can only be one of a few things .. System is working but room stats set too low? System isn't working properly and rooms aren't reaching set temperature or are taking too long? It's that time of life or they have a medical issue. Our system keeps our living room bang on the set temperature which is 21 at evenings and weekends. Despite that various members of the family feel either too hot or too cold. I get complaints it's too hot then a few hours later same person says it's cold or fine despite no change in temperature. I sometimes ask them to guess the room temperature without looking at the stat and they always get it wrong. Sometimes I pretend to turn it up/down 🙂 Making them a cup of Tea is sometimes effective. Ten mins later they are too hot.

You might get away without battens if the insulation is suitable but check with the maker. I've heard of people having problems in high traffic areas. People walking around bend the boards slightly compressing the insulation which eventually breaks up or becomes spongy.

I used the poly inserts in a ring binder. After I'd done the spreadsheet I got it to number each line and put a matching number on the plastic inserts. Probably overkill.

Council Web site should have info on the CIL. I

If you accepted his quote make sure to end your contract with him properly. Eg write recorded delivery giving him two weeks to complete the work or you will assume the contract is terminated.

We have 80mm insulation under UFH and wish we fitted more. I would stuck with rads if you only have 50mm. I think Building Regs recommend minimum 18mm thick boards over joists or similar. I would look at 20 or 21mm Engineered boards and 30mm PIR insulation if you can get it? Figure out which direction is best to run the boards. Fit 30mm PIR insulation between 30mm battens on 600mm centres. Battens at 90 degrees to the direction the boards will run. Battens glued and/or screwed down. Batten also around the perimeter and at doorways. Fit 21mm T&G Engineered wood boards (210mm wide?). They should be glued together and secret nailed to the battens. The glue applied by brush to the groove to make sure of really good coverage. Eg don't just run the glue bottle down it doesn't usually apply enough glue to the sides to the groove (according to our builder). Should allow an expansion gap around the perimeter covered by skirting. If you can afford it digging out the floor and fitting more insulation would be better.

If the CIL is a thing in your area check the status. Has it been paid? Normally a self builder has to apply for an exemption before work starts and live in the house for three years after completion otherwise it becomes payable. If not already paid, it's just possible you might become liable for the CIL with no way to claim the exemption because work has already started. This might mean it's cheaper if the existing PP has not been started. You could apply for new PP and claim the exemption before starting work on that one.

We fitted ours after completion. I had quite a problem getting the right register plate to go from the stove pipe to the chimney because the company I used kept sending the wrong parts. Apart from that it wasn't too hard.

Have you actually built the chimney already? Normally you can just raise the entry.

Part J is confusing. I think section 1.48 and 1.49 applies to all flues not just solid fuel appliances. 1.48 says "Where bends are essential, they should be angled at no more than 45° to the vertical." Diagram 15 on page 27 Part J says "90 degree bends not suitable for solid fuel". So I think for a WBS you should use 2*45 degree bends to make a 90.

Ive no idea if these are any good but.. 0.23 TOG.. https://murphylarkin.com/Thermalay-underfloor-heating-underlay-ultra-low-tog 0.303TOG (but only 2mm) https://www.ambiencehardwoodflooring.co.uk/red-classic-under-floor-heating-underlay-sold-per-10m2-roll.html Test samples?

Carpets are sometimes available in two versions, foam backed and hessian backed. The hessian backed has lower TOG but the small print in the contract with the showroom frequently says they can supply either. You might want to do something about that. Then some places say the max 2.5 includes the 18mm chipboard if it's a timber floor. https://www.diynot.com/diy/threads/conundrum-ufh-tog-values-and-underlay-for-carpet.537212/

We have a Bosch integrated fridge in kitchen units. I've never consciously heard it running. Perhaps when the door is open?

We a Our PP had a condition requiring us to agree tree protection measures before work started. We just wrote to them stating we would erect barrier fencing according to BS blah blah. They agreed it but never came to check. We just put the barriers where we wanted them. The main thing they want to stop is vehicles driving over the root zone. So if you can stop that with fencing in strategic places but allow your scaffolding you should be fine. So fence off the trees while digging foundation trenches then fence off the route vehicles would have to take to get to the trees while your scaffolding is up.