Temp

The more I think about it the less I like the idea. Can it possibly be rigid enough to tile over reliably?

I would fit big rads. Possible UFH in the walls? Aerogel is the best insulation known to man but is only about twice as good as PIR. We have 80mm PIR under UFH and wish we had more. If you really must have UFH perhaps look at a system that doesn't need screed. Even liquid screeds typically need to be 40mm thick because the UFH pipe reduces the thickness locally. This 18mm or 25mm system claims it can be tiled over without screed.. https://www.continal.co.uk/system/tilefix I think good floor tiles are going to be 10mm thick plus 5mm adhesive. Thin tiles might not be strong enough for point loads over these type of UFH system? 15+25=40mm It might be possible to find a 10mm insulation you can put under the UFH panels.

See page 20 and 21 of the installation manual. Looks possible if there aren't any openings nearby (I mean if the slope is ok).. https://mediacdn.baxi.co.uk/-/media/websites/baxiuk/files/product-literature/baxi-platinum-combi/baxi_platinum_combi_installation_and_service_manual.pdf

Clay soil can sometimes require special foundations. Depends if it expands and contracts with the seasons. Sometimes you need to line the trenches with compressible boards before filling with concrete. You BCO may have have a view on this. Sometimes they require a ground condition report/soil survey to support your proposed foundation design.

The government could regulate to require funds to be held in a separate client account until after delivery or possible even require use of a third party escrow account.

Normally the DPC is roughly 150mm above ground level so I would dig down 1600+150 = 1750 mm below the existing DPC. Then after the BCO is happy fill them with concrete to a suitable multiple of brick or block courses below the DPC. For example 1 block course on the inner leaf and 3 brick courses on the outer leaf should be the same height (but check your bricks and blocks). Alternatively 2 blocks and 6 bricks etc. Then when you lay those courses your DPC will end up at the same height as the house.

Think the strength will depend mostly on the screw, how secure it is in the wood and how many along the bottom. The plastic is just to protect the glass edge from the screw. Tiny stress cracks can cause toughened glass to shatter. For same reason never stand toughened glass on concrete, tiles or stone.

Just replace with similar gas combi.

Something like this? https://www.omegabuild.com/shop/shop.php?category=secondary-glazing-fittings-easyfix-edging https://www.amazon.co.uk/s?k=secondary+glazing+fixings&adgrpid=126785493076&gclid=Cj0KCQjwyOuYBhCGARIsAIdGQROLktcHw02jG1vgMCeVkQrLrjesB6eIJsXgyeUmyD3Fgjd2tuwMySkaAm7iEALw_wcB&hvadid=543083316377&hvdev=t&hvlocphy=1006818&hvnetw=g&hvqmt=e&hvrand=7320255020270910883&hvtargid=kwd-360730112349&hydadcr=28181_1821134&tag=googhydr-21&ref=pd_sl_56z4dawksr_e

So possibly bad luck those of us who filled up their tank recently 😞

Just a heads up on earthing.. In many cases you shouldn't export the earth from the house to an outbuilding. There should be an earth rod at the outbuilding instead. A common set up involves: A MCB is fitted in the House CU. Rating depends on the cable. The cable braid is connected to earth at the house CU end only. At the outbuilding a "Garage CU" is installed. These are typically supplied with an RCD and two MCB (lighting and power). The Earth in the Garage CU is connected to an Earth rod hammered in the ground near the outbuilding. Edit: Your water pump could be plugged into a 13A socket on the power ring in the outbuilding. I think it may also be possible/better to wire it into an FSU.

A lot depends on your attitude to risk. Official advice in the UK from the HSE says keep stored hot water above 60 and cold water below 20C.

From the USA (yes I know their systems are different).. https://pubmed.ncbi.nlm.nih.gov/31940510/

Press reports say they are going to do something for those that use heating oil.

Calculator here.. https://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html Suggests 4mm^2 SWA underground is OK for about 7KW and 6mm^2 about 9kW. Main thing to check is the exact cable length. It's easy to forget you might need 4-5m each end.

Hope he wasn't too upset at being called out for a fault 🙂

In case its not obvious.. you should probably aim for at least double the insulation required by the Building Regs.

+1 although it might even cost you money if you don't know what you are doing. If you are made of money you could easily spend.. Builder 10-15% Architect - managing the builder (technical/quality and schedule issues) 11% Quantity Surveyor - managing the builder (stage valuations and stage payments) 10%.

30kW of PV is about the biggest system I've ever heard of on a house. That's going to be around £21k or £100 per square meter. Edit: without a battery. Tile/stone flooring works best with UFH but costs around £100-£130 per square meter according to checkatrade. Some stone is double that or more buy the time it's stuck down and sealed.

The issue is the 50mm void must be ventilated at the eaves and ridge. Ventilating at the ridge means every rafter bay as there is no lateral air flow due to the rafters. So the best solution involves replacing the ridge tiles with a ventilated ridge rather than individual vents. Some care is needed at the eaves to ensure the air goes up the 50/75mm void rather than into the floor or the loft itself which you are trying to keep warm... but it's doable. I would use 125mm fixings for 100mm insulation. Under the insulation fit a vapour barrier (plastic sheet) or possibly foil tape the joints in the foil covered insulation. Then plasterboard.

For stud walls one technique to reduce sound transmission is to have two staggered sets of studs, each supporting the plasterboard on one side. That way no sound transmitted through the studwork. Sound insulation can be woven between the two sets of studs. Sometimes two layers of plasterboard are used each side to increase the mass. Applying that to a flat roof you would effectively add a false ceiling. Eg one deep set of rafters would support the thermal insulation, OSB and EPDM etc. Then below/between that another set of ceiling joists (can be less deep) supporting just the plasterboard. if its a warm roof (all thermal insulation above the rafters not between) then this would increase the depth of the roof by perhaps another 50-75mm. Again sound insulation would be woven between the two sets. Another possibility would be to use resilient bars between the regular rafters and plasterboard, possibly doubling up the plasterboard to increase its mass. That would probably add 25-30mm.

Think I would fit it as you have it in the photo. The wall plates must be straight and parallel to each other. Otherwise every rafter would have to be a different length. I assume the absence of a fasia board is to ventilate the cold roof? Another approach would be to have external birds mouth and project the rafters beyond the wall board. I quite like the look of exposed rafter ends.

Do you know how much you export? At best a battery should allow you to use that rather than export it

Perhaps of interest. Ripple energy allow you to buy a share in a wind farm. https://rippleenergy.com/ https://rippleenergy.com/how-it-works

Google suggests you can buy matt stone sealer but not used it myself. We just used regular lithofin. Its pretty matt but gets a soft sheen in trafficked areas over time.