Conor

I can highly recommend 70mm metal studs. We have 70mm wall with 50mm accoustic insulation, 18mm ply lined on one side and 12.5mm plasterboard on each side. We have this between our two offices and you can't hear a thing through it.

Was there an edge insulation/expansion strip installed around all the walls? Usually a light strip of foam that's stapled or glued to all the walls before the screed is poured. Also along the edge of your patio doors. It's there to allow the screed to expand and contract without being constrained by the walls.

Can you them on flat ground with a length of timber at each end and stack a few concrete blocks in the middle to take the bow out? We had a few dismantled IKEA wardrobes in storage and the same thing happened to the sides and doors. I set them on the ground on top of 4" timbers at the ends and set a block on the middle. Worked a treat. You might need a bit more weight tho.

Our thermostatic bath tap said the same but works fine with ~40⁰c water. In fact all of our thermostatic taps say something like min 50 or 55c.

It probably did and you've dropped it or its stuck in the packaging... Took me an entire weekend of fiddling and refitting my Quooker tap before I realised I'd lost one of the weird sized fibre washers. Never did find it and had to buy a big box of mixed washers to get one roughly the right size.

Type up a rough list in an email and send it on to a few builders and plumbing merchants and see what they come back with. Doesn't need to be exact or fully complete, just enough to get an idea E.g. 10x coils of 200m 16mm PERT pipe 2000 60mm ufh staples 3x 8m lift 28mm circulating pumps 3x 8 port stainless steel manifolds 3x 22mm actuated valves 50m 22mm PET pipe. Then take it from there and finalise the list with your chosen merchant. I did this and saved over £1k.

Sorry, not much help other than to double check where the water is coming from and to try PTFE on the male threads. My plumber leant me his, couldn't figure out how to connect it to the UFH manifold so connected the garden hose to the drain valve instead 🤣

What's the rest of the floor build up? I'm assuming there will just be screed on top? Where is the tanking membrane in this design? Do you have drainage under the slab? If the insualtion is perpetually wet, it won't work so well! Your engineer is basically suggesting an insulated raft foundation, which is the best type of foundation in the world* *I am not a structural engineer

My friends had designed a straw bale house (bales as structure, lime render either side) and were going to use dry stone trench foundations. Unfortunately project fell through and never happened. I'm assuming as you are avoiding cement you're mindful of the embodied carbon of the build? Have you down a whole life carbon assessment of the build or is this a ideological decision? You'd be surprised how little impact a small amount of the right concrete in the founds will make in the overall carbon impact of a build. A couple courses of 7n concrete blocks would be nothing over the life span of the building. We looked at using low carbon concrete in our build, but wasn't feasible as it would have to have been mixed on site which wasn't an option for the grade and type of concrete needed.

It depends. Can be done either way. If you are keying together blockwork, roof structure etc then you'd pin the foundation together. But you can also have the new structure independent from the old one, I e. Have a gap between the blockwork and fill later with mastic. You then don't pin the founds as you want them to move independently. We did the latter as the new foundations needed to be deeper an lower than the original so wouldn't have worked anyway. 2 Speak to you SE.

Limecrete? See it used a fair bit here.

Any rubble? Fire in a few broken bricks and leave good gaps and you'll have the amount of concrete needed.

Some advice from new bifold owner here. We have a 4.6m X 2.6m opening and have five leaf doors. The leaves are triple glazed and not far from the weight limit from the manufacturer. The room is noticeably cooler than the rest of the house as the doors, even though they are pretty much the best on the market and cost more than our kitchen, perform nowhere near as well as a single pane. Your limitation will be leaf weight limit, and that will mean you'll be getting the thinnest possible double glazed units. Having more glass to frame ratio, however, works to your favour. You'll either need to change to sliders or accept a poorer performing system.

A above, issue isn't the 25mm to each pods it's the 32mm pipe. Lay a 63mm pipe. Or have have a gravity storage tank on the site with pumped feeds to each pod. I'm not sure what you mean by looping the 32mm pipe, but if it's just looping around the pods and not all the way back to the connection, then it won't make much of a difference. Work out the cost difference between a storage and pump system to a new 63mm connection (or three additional 32mm connections which is roughly equivalent) and take it from there.

I know a guy that has. Think he has a 24pKw array and a room full of batteries. Passive House so minimal heat load. Was denied permission for a wind turbine.

50mm rolls cost £35 in the summer, £48 back in Jan. Add that rise on and that means doubling of price on a year.

We went for AAVs. One in concealed cistern and other in cupboard. No issues so far and BCO happy.

I drilled dozens of big holes with my titan sds drill. The slip clutch is essential. Also borrowed sparks core drill. Not a whole load of difference tbh. It's really tough work. Set yourself up on a proper platform so you can keep the drill level and your weight behind it. Ladder is no use. Oh the dust. The dust. Wear all the masks. For the holes through the 200mm RC walls I hired a guy... Best money spent!!!

That's a good point. The majority of the cost of my install was the mounting kit and inverter. Panels £2k, everything else £3k.

I think the cheapest is an ASHP running on economy 7 or other night rate tarrif. Works out at about 2-3p per kWh of heat output Vs 6p or more for gas. Who knows what it'll be in the future, bit I can't see gas coming down in price ever again. If definitely gas, go for an UVC as gives you the ability to switch to other heating source in the future, use solar PV to heat hot water ( a bigger energy component in a well imsualted house than people think) and run multiple hot water outlets at the same time. A combi is a far cheaper install (£1k easily) and takes up less space. Have you designed in the required plant space, service voids, floor build up etc for all these options?

No bother. Btw, I've a LOAD of ventilation, plumbing, screws, etc left over that will be going on gumtree very soon. Let me know of you're interested in anything.

Sorry, terminology borrowed from my industry. You need one of these, ideally sitting on a bit of cement. https://www.diy.com/departments/floplast-underground-drainage-rest-bend-285123-dia-110mm-l-132mm/81473_BQ.prd Everything before this bend should be black. I'd highly advise adding a soil vent pipe up the side of the house. You'd connect to a T piece coming out of the wall and up to a suitable height away from Windows and openings.

Keep it simple. Keep boiler, PV on roof to offset your day to day usage and a solar diverter to heat your UVC during the sunny days. Go to town on your extension air tightness and insualtion (200mm full fill cavities, 150mm PIR in floor or 300mm EPS, basically passive standards) so your minimising the additional heat load of the building replace your crappy double glazing with decent triple.

All I'll say is our house ended far bigger than we thought/needed.

That's underground pipe. It's not UV stabilised and should not be used above ground. You want to replace that pipe with either the same type and cover it, or black PVC pipe to ground level bend and cover. It wouldn't be hard to pull those apart and replace. Likely the seals have pulled out or the pipe has become porus. You need to make sure the bottom bend has a duck foot and is set firm, and the vertical pipe is clipped to the wall or a support. Finally, is there a vent pipe or air admittance valve on that branch? From the description it's just servicing a single toilet then presumably connects to the sewer outside.