Conor

We (water mains designers) try to keep dead legs under 5x the pipe diameter. E.g a 50mm ID capped pipe would have to be 250mm or less in length. At this length turbulence is sufficient to refresh the water in the leg. Any longer, and the water will be stale and potentially harbour bacteria. However, if you have a way to flush out the leg, then it doesn't really matter as the risk only presents when for some reason the dead water enters the rest of the pipe network. Fyi I've seem some terrifyingly dirty water washed out of hydrants and scour pipes in my time. I'm amazed I still drink tap water

I think it suits the plot very well, she's done a good job. Though it's hard to tell without elevation drawings. We started off with an aim of a 4 bed within about 180m2. That's crept up to 200m² because of a large open plan space. Regarding bedrooms, our architect sticks to a min of 3.3 X 2.7m for a double bedroom. Our. master is 4x4.5m Your other rooms are very similar to ours. If you visit a developer's 4 bed show house you'll soon see your design is more than generous. Would it be possible to square off the transition from one wing to the other? The extra corner is not only more complicated, it removes habitable space and is a bit less thermally efficient (you want a smallest surface area to volume ratio practically possible). I think there is scope to simplify the design and increase floor area to 200m² and stay within budget. You'll get much more value out of an extra bedroom or office, than a fancy kitchen.

Your architect needs a slap for coming up with such a poorly performing design that isn't even meeting minimum standards. Even though you'll be moving on in a few years, please bear in mind your house will be around for another 100 years or more. You should be aiming to blow through the SAP requirements, not scrape though. As above, make cavities 150mm wide, put in 150mm insulation in the floors, 400mm in the loft and consider higher performing windows and doors. And airtightness, makes a huge difference. It will of course add some cost to your build, but you'll have a much more comfortable house and a better legacy for the future.

Nice one. Did you do much in the way of air-tightness work? What are you doing for buffer tank and cylinder? I'm tempted to get the whole package from them.

(possible unreliable anneicdote content) I visited a guy's house that does PV and off-grid installations. He had 20pkw array, and was planning a wind turbine. His rule for installations up here in the dizzy latitudes was to install 4x your typical daily demand. basically because PV production in the winter is 1/4 of the summer. Battery storage flattens the demand during the day, allowing to run a kettle and oven at the same time, even if you're only producing a couple kw.

I'd never build a wall without a concrete foundation. It'll fall over eventually. Line any face of the wall that in in contact with oil/water. Really think about your drainage and make sure water can move freely away from the back of the walls

Most structural attachments (e.g. steel beams, floor joists) to an ICF wall are from the inside, so it's better to have less soft stuff to cut way, minimising cold bridging.

How much is delivery stinging you? Assuming it's a full pallet or two?

I'm looking at them for a heatpump/buffer/cylinder etc. Interesting to hear how you get on with it.

I second the comments above, save the £8k or so on a heat pump installation and put it towards more insulation/ fabric improvements in the house. Gas isn't going away anytime in the next 30 years, prices can't go up too much as will push millions of people in to fuel poverty.

Clear masonry waterproofer. Will stop the bricks soaking up water.

I have a basic Macalister one from B&Q... It's invaluable! Can lift very bulky and heavy loads. Has pneumatic tyres and only needed topped up once in the last year. It basically lives outside. Lasting well. Whatever one you get, make sure it has the drop down extension bars. Makes it's easier to lift bulky loads.

Your solar diverter to the immersion will kick in once PV generation exceeds what your house is consuming. In the depths of winter you'd have to have most appliances off for there to be any excess generation.

My OH that is slowly coming around to the idea sent me a link to somebody that basically built a glass house over a pond and converted it in to a pool. She's a much keener swimmer than me... Things could escalate from just a simple semi-clean pond!

Deffo need to do some calcs. Ground temp is lower than air temp for almost all of the summer, so most heat that is embedded in the water will transfer to the ground, rather than radiate to the air. I'm hoping I can make use of the house's ASHP and UFH system to do some sort of heating when there's enough electricity from the PV to make it free/cheap. I'd also like to explore simply circulating the UFH through the house and to the pool when the floor slab temperature is >22c, so effectively using the pond to cool the house and house to warm the pond. No idea of how to set that up or flow rates. The pond will have at least 100m³ of water in it, a massive heat battery! I'll need a spreadsheet....

We would both swim in the sea and I'm a (retired) surfer so used to swimming in water 12-15c... 17c at the very best! I'd be happy with 20-22c for quick dips from june-sept. That's just above average air temp so I'm hoping to achieve that with a combination of insulation and a bit of passive solar heating / heat exchange with the house. We're talking 30min swims at the most. I've just bought a book on the subject and I'll carefully consider everything over the next year. Definitely a post build project. I think we'll just level the site and forgo landscaping until next year.

That's basically a cube. Might be worth speaking to local concrete suppliered and see if you can get a mini mix delivers? You don't want to do it on two pours. You can pour straight on to the clay, just scrape away any sludge.

Well, I've ordered a book on natural pool design and I've started to wear down the project funder... I'd say we'll put off the major landscaping until next year. Plenty of time to get a design (and permission) figured out. @Iceverge not a million miles away from some of the design concepts out there. You put a flat base in, build up walls to form the deep swimming area, fill the outside between the edges and the walls with gravel and clay to form the shallow living area.

I want a swimming pool but there is absolutely no budget for it. Also want a pond. May as well combine the two. Anybody ever done a pond for swimming in? I.e. a deep pool with a filter bed and shallow area with plants to maintain clear water? Not been able to find a whole load on line. We will have major landscaping, drainage and retention wall works happening later in the year so it's now or never. https://www.impressiveinteriordesign.com/diy-natural-swimming-pool/ Being in Northern Ireland, we'd probably need some sort of heating to take the chill off.... UFH loop in the base???!

Bear in mind that as bats are a protected species, this is more than getting around planning restrictions. I would not do anything at all (even ground works) until you've had the OK from a bat ecologist. You've been made aware of the bats, so any activities that result in their disruption or harm (e.g. construction noise/vibration or dust) would likely be looked at very harshly. We wanted to do works on a barn door (in a timber water treatment plant) to get electric cables through for temporary pumps, and the solution our ecologist made us follow was the careful removal of the doors, move them away from the building so we could then drill out holes for the temporary cables and hoses. The noise/vibration could cause the bats to flee their roosts.

It's encased in 200mm of reinforced concrete, it's not going anywhere.

Open fires have a net cooling effect as they draw out more heat energy (the warm air) than they radiate out (don't know about back boilers). They have no place in our world anymore. There's a house (about 150m²) that's just got fpp across the road from us and they have three open fires and a wood fired pizza oven in their house design... It'll either be freezing or unbearably warm ?. Not sure how they'll pass their air tightness test. And your MVHR won't work properly at all, esp when it's windy or the fire is lit. So you'll be better off with trickle vents and bathroom extractors. And you'll also need a wall vent in the rooms where the fires are, so even draughtier. I think a room sealed stove is the obvious compromise.... You can always fire the door open for effect when the mood takes you. Sorry to be negative, but that's the reality.

Lhs line is the main vent stack with basement toilet connecting to it, them to the right we have the basin and shower, and finally utility sink / DW in next room. We originally had the toilet in same line as main soil stack from above, but BC asked us to put it in with basin and shower for some reason as it obviously meant the toilet line would be more than 6m unvented.

Do you ever think you'll sell the house? Of yes, then stick in a small ASHP as you'll have have difficulties selling a house without central heating. I think we're a decade or two away from unheated passive houses being widely understood and accepted.

Same when we did our extension. Had a spark to 90%, then I added some eternal sockets and extended a loop to my shed. BCO didn't care. I was worried I wasn't going to get signed off.