Iceverge

It's in the Hep manual so I assume it's ok. Our resident Parish Priest of Piping does advocate hep- hep push fitting-copper-compression though.

Plastic bags and tape. I still got some scratches though so I just pulled through enough pipe until I got to a place that wasn't scratched and discarded the excess. It still sealed pretty well to be fair despite non perfect pipe in places. I've don't a dozen or so compression joints with brass and the SS inserts despite @Nickfromwales best advice. No issues so far..................

This is what I use. It's the only protection I have ever had that properly seals around your eyes but doesn't fog up. 5 mins is plenty though. The thought of wearing it whilst insulating as attic fills me with dread.

Has anyone tried one of the fan assisted ones. I like the idea as they might actually be comfortable and shouldn't fog up. a bit Dear Mind you at £336

I would use mineral wool between the studs. (As a second to blown cellulose) Almost zero waste,all offcuts can be tucked in somewhere. It can move with the timber as it expands and contracts. Better for fire protection, sound protection, decrement delay. Easy and fast to fit well. Get a bread knife and cut it slightly large and it tucks in perfectly. For a 140mm stud wall with a continuous internal of PIR like @Thorfun just bump that layer by 10mm and you are at the same U value. @saveasteading did you consider Using something like a mineral wool full fill batt and a 22mm insulated plasterboard for less labour overall?

I suspect you are thinking of Tapco or similar. I would say the planners wouldn't notice the difference having seen them in the flesh.

Yup! Have a look at the way these guys do roofs. Nowhere for a leaf to get caught and the walls are super protected from the rain. https://www.makar.co.uk/portfolio Also I think you're missing a trick by not having carport access to the house under cover. We didn't and it's a regular sprint thought the rain with the kids to the car.

I would say it is a variation of the long house but with some sticky out bits that have parapets and flat roofs. Fine in the Santorini with 340mm of precipitation but in western Scotland with 1500mm of rain annually I think it's asking for trouble. Here is the ground floor suggested build up. The U value at a guesstimate is 0.4W/m2K.

Ah bugger..................... Another Architect who has been taken out for lunch by the Kingspan salesman, shoved a little book with nice copy and paste details and told " this will solve all your problems". They've left you with an expensive option and a non compliant U value ( unless you magically stop all air infiltration and convection inside the unventilated layers of air in the wall build-up). I've written another post on this. Here's a quick calculation of the wall as proposed. It'll be worse in reality as the Kooltherm boards will certainly not be sealed 100% to the timbers and you'll get thermal looping (moving air inside the wall). They're very thin also at 285mm. Architects tend to be very good at concept, usability and balance of designs but alas many fall down on the practicalities of actually building a house. I know this isn't what you want to hear but I'd be tempted to fix the design into something better on paper now before going any further down the building route. Go for thicker walls and make sure all the structure is covered by a pitched roof, balcony included. Get rid of the parapet walls and the bay window. They're going to leak water and air and heat long term. Ensure that no element of the house cannot be easily brought in on a flatbed trailer and can be lifted into place without any large equipment. Sorry if I'm being a killjoy but it annoys me to see professionals being so careless with their customers money. Do you have planning permission yet?

I've had a quick scan of your plans. Your architect has made the walls very thin. Maybe 300mm? You might struggle to get to BRegs with this. Have you robust details for the parapet walls and flat roof. These need to be bomb proof. Especially with timberframe.

Also what is your predicted electric price for 10 years? If you have an option of cheap overnight electricity it may be better not to install any heat pump but just enjoy the low capital outlay and trouble free operation of an immersion and a few storage heaters. For info 186m2 in the south of Ireland we use about 3200kWh for space heating and 3650kWh for a family of 4. Passive insulation levels.

I think your professional has wildly over estimated the heat loss. That is almost 6 times passivhaus levels and you have near passivhaus insulation. Have you tried consulting the heat loss spreadsheet on here to see if your predicted losses are that high?

I wouldn't over think it. Your buildings loadings will be minimal. Go for a 100mm+ slab with some reinforcing mesh and pour it all as one. Any slight movements of the building will all go together then at least after construction. You could get a structural engineer to design it properly but would cost far more than a bit of extra concrete if you're apprehensive about the strength.

Have you considered soil nailing? https://www.designingbuildings.co.uk/wiki/Soil_nailing

Have a look at this video from 9:50. I wish we'd done it in our house.

Ask who ever is signing off your house what paperwork they normally require from the plumber. I suspect they'll be confused by the question. So long as your place complies with the building regs it's unlightly anyone will ask for anything beyond that. The one thing I would get a plumber for is the gas connections for a split unit ASHP. Everything else I would be happy to DIY. I redid all our DHW after the plumber made a mess of it. As for insurance I would far prefer to put my money into a good install and a really redundant design. Ensure that every room where a pipe is jointed has a floor drain. You're half way there with wet room showers. That way if a fitting fails when you're away for the weekend you'll just have to turn off the stopcock, mop slightly wet floor and replace a tap or T joint. Far easier than chasing an insurance company for months to remodel the whole house.

EPS. As much insulation as you can. >150mm Concrete strength >30N at a guess. Mesh for a raft yes. Yes. It's a french drain.

You could slightly curved sheets to do the whole span from a metal supplier. Fix some roofing membrane underneath to catch any drips and tec-screw them together. Simple job.

Demo and rebuild! Its the only way😬.

Well done on the insulation. You won't need much heating at all. A cheap second hand storage heater could allow you to shift all the load to a cheaper tarrif. UFH mats over a slab would be able to achieve this to a limited extent too. I think they'll be fine.

As close as possible to the kitchen tap as possible is best for a quick time to hot. Then run 10mm pipes to the basins for speed of delivery there. The warm up time doesn't really matter as much for showers and not at all for baths.

Guage Pitch Length Alternatively (and I'd recommend this) sharpen the chain. The chainsawing experience is night and day with a sharp chain. I couldn't make any fair attempt of it until I bought one of these. Also sold as Stihl. I have a knock off and it works well too.

@jon3 The house I grew up in was regularly 12deg overnight. Icy noses and fog from your breath, mould on the walls and everyone always had a cold. The only practical way I can see happening for a modern building is to make an uninsulated "storage space" in the attic, plasterboard it out and use it as a bedroom. Ensure you have a huge amount of ventilation however as it'll quickly get mouldy otherwise.

@alfaTom Welcome Welcome Welcome. Looks like a nice spot from the top pic. Excellent News. Have you considered burning it down?

I assume that you'll be insulating from above with mineral wool? If so just cut an appropriate triangular shape of mineral wool and shove it up there, careful not to block eaves ventilation if it's required. ( I've forgotten your roof Construction) . Then use airtight tape and membrane to seal the window to the wall. Then screw in J beads into the window and slot in your plasterboard.