Temp

I think that's going to be considered "non-standard construction" by the Mortgage industry. I would seek advice from a valuer/estate agents to see what impact it might have on the final value. Might be worth knocking it down and building a semi or even two detached houses. https://www.homeprotect.co.uk/non-standard-construction-insurance/buying-a-non-standard-home

Regarding cavities... The Building Regulations are somewhat vague but they are the ONLY legal requirements. The so called "Approved Documents" is what most people work to.. https://www.gov.uk/government/collections/approved-documents These outline ways of meeting the Building Regulations. They are not legal requirements so you are free to adopt other ways of complying, however BCO sometimes treat them as if they are mandatory and the only way of complying. Approved Document C covers water ingress.. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/431943/BR_PDF_AD_C_2013.pdf Each Approved Doc has a section in green near the beginning that references the relevant section of the Building Regulations (the law). In this case see page 5. Diagram 11 on page 33 covers external insulation. If the walls are concrete I would suggest the nearest option is top left (External Insulation of solid walls). Thats EWI with a cladding board and render or similar waterproof "protective system". However there is a section for "framed" external walls. This was probably intended to refer to timber framing but the BCO might interpret it to mean any type of framing (eg concrete posts and concrete panels). That option is EWI, Membrane, Cavity, Cladding. You will have to propose whatever external cladding solution you want and see what the BCO says. As for how thick the insulation deeds to be that's a whole different ball game and I'm out of date with the figures.

Some Building Control Officers will try and tell you a cavity is necessary but that's not in the Building Regs. Of more concern is what mortgage companies think. If they see it as a "non-traditional construction" then buyers will have a harder time getting a mortgage and valuations will be lower. What sort of foundations and floor has it got? Is it just a timber frame sat on a concrete slab like a shed or does it have proper trench foundations?

I've had a quick look at the wiring diagram for "a" Wirsbo Cosy 24V stat... https://www.uponor.co.uk/-/media/country-specific/uk/download-centre/support/manuals/legacy/cosywirsbo/cosy-wired-manual.pdf?la=en-gb&hash=B38C92FA92FB3D52591E387F7F3D06AC2A380540 and the Danfos TP5000M 24 Si. https://assets.danfoss.com/documents/DOC041186407154/DOC041186407154.pdf I think you would need a wire link in the TP5000Si but otherwise I reckon they could be used to replace the Wirsbo Cosy stats. I believe the existing stat has.. Terminal 2 → Phase 24V Terminal 3 → Switched phase Terminal 4 → Neutral 24V The TP5000M 24 Si has.. A → 0V B → 24V and relay contacts.. 1 → OFF 2 → Com 3 → ON So I think the wiring would be... Wire TP5000M 24 Si Contacts Phase 24V --------------------------- B and 2 (eg using wire link) Switched Phase ------------------- 3 Neutral 24V -------------------------- A I recommend taking a photo of the back of an existing stat before disconnecting any wires. Oh and turning off power to the whole system but that's obvious.

Perhaps ask them if the HTRS230 is a direct replacement for the ERT32 https://salus-controls.com/uk/product/htrs230/

The key thing is to try and make the going and rising the same for all steps otherwise it becomes a trip hazard. This requires careful planning if you are adding steps to an existing staircase.

Perhaps someone used car under sealer ?

Some thoughts.. Most likely it will need more insulation both thermal and sound. Part L for thermal and Part E for sound. The roof overhang looks a bit small for external wall insulation so the roof might require mods. Is there insulation in the floor already? As for sound insulation I think walls between separate flats need to meet Part E1 (walls between rooms in the same dwelling need to meet E2). There is also a section E3 for walls separating dwellings from corridors. This summary is from somewhere that wants to sell sound proofing stuff that you may not need but gives an overview of the regs.. https://www.soundproofingstore.co.uk/how-to-pass-part-e-building-regulations The wall between the two dwellings will also need to be 60min fire rated (I think) and extend up into any roof space to prevent fire spreading from one to the other up there. Think that need either one layer of something like Gyproc Fireline or two of ordinary Gyproc wall board each side. The electrics will need separating into two with two meters etc. Ditto water and ideally sewerage. It looks like the windows only have top openers? Some may have to be changed so the bottom opens to meet fire escape regs. But perhaps all the windows need changing for other reasons? Got any oil storage tanks near?

Never used them but this place appears to sell small quantities.. click on pic of bricks then whers it says "choose" you can change it to "corner packs -...".. https://mybrickwall.co.uk/?gclid=CjwKCAjwlID8BRAFEiwAnUoK1V6bVP0jrr9iR1Wf-cMXK4uLC0iBs6RNE9RgZ34vYfxWwadzxlHkeBoCEroQAvD_BwE

My understanding is that until the end of the year you should pay ROI VAT and freclaim it like any other material you buy. The big unknown is how VAT is processed after the end of the year. My understanding is that in the event of a no deal exports to the UK should be ROI VAT free and UK VAT will be charged when the goods arrive in the UK. Then you reclaim the UK VAT. The problem will be if the supplier won't export VAT free. My guess is you will have to pay both and only be able to reclaim the UK VAT. There may also be UK duty to pay on goods arriving next year and that cannot be reclaimed. I would make sure delivery is well this side of year end.

Last i heard house building is back to precovid levels so perhaps suppliers have been caught short of stock?.

That's unfortunate. Means the bco may want a 50mm deep ventilated void between membrane and insulation to avoid interstitial condensation.

Definitly reclaimable (Brexit changes allowing). Many of us have reclaimed vat on purchases from Europe, Belgium in my case.

Possible insulated roof panels.. https://www.panelsell.co.uk/insulated-roof-panels?source=google&medium=adwords&campaign=1614494041&adgroup=62109888958&keyword=insulated roof panels&matchtype=e&adposition=&device=t&network=g&gclid=CjwKCAjwlID8BRAFEiwAnUoK1bB9upYPK1cPN1_smpBo1Oyz_koIJikm6xUO6Dz63dWeO66Hd_rhWRoC--cQAvD_BwE Add more insulation below.

Trivia: Balsa wood is technically a hardwood. We went with Oak and despite protecting it managed to get some dings during construction.

Although stepped flashing does look good when done right.

Just curious but are they mains powered with a battery backup that's meant to last 10 years or does the battery power them all the time?

What span are the rafters? Is the membrane under the tiles vapour permeable? If it is then you can save 50mm by not needing a ventilated void between it and the insulation. Aerogel is the best insulation in the world (last I heard) but at best it's only twice as good as PIR and very expensive if you can get it. Most aerogel insulation isn't in its pure form because it's too fragile so the insulation properties aren't twice as good as PIR.

I think it might help to know what sort of temper you run the existing store at and the UFH flow temperatures needed to keep those rooms warm?

Yes we have about 80mm of PIR then beam and block floor. If building again I would go for much more.

Which you can reclaim at the end as its a conversion.

That would be a bodge. The flat roof almost certainly has a vertical upstand hidden by the bottom row of slates that stops water running under the slates from getting into the house. The correct thing to do would be to temporarily remove a row or two of slates and redo the flat roof and upstand properly before replacing the slates.

How about dual pitch roof each 2.5m... some rough calculations.. 2.5 * tan(8) = 0.35cm 3m max height at ridge works out at 2.65 at the walls. Less thickness of roof say 300mm gives 2.2m high walls? With such a short span of each pitch perhaps no need to overlap metal sheets so less pitch might be allowed? Just thinking aloud.

Not just BC. The planners would also start rubbing their hands together.

Others may disagree but I would have a rethink. If you put down 18mm osb then 18mm engineered Wood you end up with 36mm overall. We have 21mm in a house built to Building regs standards as they were in 2005-7. We have found we need quite high flow temperatures to push enough heat into the rooms. In addition the return temperatures can be quite high sometimes. There are other threads on here where I suspect having too much wood above the ufh might be the reason they are seeing long warm up times.