Conor

Ok, from my point of view from the water industry. We'd always avoid doing this. And you'd never have the water pipe in the same bedding material as the sewer, especially below. The scenario is that a leak in the waste system could enter the water pipe if it were at the same level or lower and in the same bedding material as the waste pipe. (This scenario can easily happen if you have a leaking pipe and low pressure or no water event, when the hydrostatic pressure in the ground is greater than in the pipe) This has happened in public water supplies and lead to serious health incidents. You will need to bury your water pipe at about 900mm deep. See what the invert requirements are for your waste and take it from there. If the water pipe is more than 400mm (100mm bedding for each service separated with clay) deeper than than the required depth for the water pipe, you'll be fine.

Consensus is that in the north of the UK you can complete a modest house for £1k/m² (if you get your hands dirty) or less. We're in NI and are aiming for £1k for finished areas and £500 for basement as it will be a shell only, so £850/m² overall for 300m² = £255k. And not a penny more lol. Bear in mind there are economies of scale.... A 200m² two story house will cost 50% more than a single story 100m² house (before furnishing etc) rather than double. (I could be totally wrong)

We're building a full footprint basement as part of our project. We looked at various scenarios (split level, partial basement, no basement but bigger footprint) and the full basement came out best value for money. I think I calculated it as an extra £400/m² compared to standard ground floor build, but we get an extra 100m² of space. - we have a limited footprint to work with, in order to get a 4 bed house, we either need a bedroom on ground floor or in a basement. - we are on a sloping site, so have to deal with a 1.5m fall from front to back of house regardless. - rear aspect of basement will be at ground level - we will have a utility/laundry room, plant area, cold storage room, plus a large "store" that could be used as a gym/play room/study etc in future- no money for that now but have included an escape window at least. -hope fully having a dumbwaiter (3£k) from 1st floor to laundry room. Otherwise navigating two flights of stairs with laundry baskets would be unnaceptable for my partner (mobility issues) - costs have come back and raw construction cost is about £10k more than building the same 100m² at ground level - about £6k of that is tanking and £4k ground works. It's a standard concrete raft with ICF walls- exactly that same as if it were at ground level. -expect to be another £5k of additional costs in form of extra retaining walls and drainage/landscaping costs. We will be able to have a (sparce) completed basement at passive standard for less than £1k/m² -Our heat pump will be approx 10m from the plant Room.... As long as the pipework is internal, right diameter and insulated, it doesn't matter really. -mvhr is having to go in a hallway as needs to be on an external aspect wall. -to save money and embrace the basement feel... We aren't having suspended ceilings, walls will be painted block, (ICF walls will be lined with ply) electric fittings will be surface mounted, floor will be poured resin or vinyl. No skirtings etc.

Run it in extract only mode* *I'm really, really, not an expert I'm just repeating what my MVHR designer neighbour told me once. In theory it shouldn't work very well, but it does, apparently.

Normally you start the ICF one course below DPC level on top of your footings. You'd then use water proofer in your concrete for the below ground block and first course of ICF. This acts as your dpc. If your Brockie has no experience of using ICF, you're probably much better teaching yourself online and doing that part of the work. It's not at all like block laying.

You'll need an engineer (+drawings) plus building control approval before you start. When we did similar in our last house, we had an interred "T" beam put in along where the supporting was was, and new joists spliced in where required. Ceiling was then reboarded. The inverted T beam allowed the beam to be inserted without having to remove existing joists. Builder just had to cut a notch though the joists and slot in the new beam.

50mm of EPS will be about 0.5 and 150mm PIR will be 0.12. huge difference. Our "garage" will be made with ICF and I'll put in 100mm EPS under the slab... Its more for keeping a stable temperature all year round rather than aiming to have it as a heated space.

100% agree. Nightmare. When we propose pipeline routes, we always assume land within 10m of a petrol station, workshop or similar is contaminated, and we make sure the pipeline goes on the opposite side of the road. It's just not worth the risk.

So, here's my story. We originally wanted an insulated raft for our build (2.5 story ICF build Inc 100m² basement). Loads of promises etc from the sales people. When the SE started her calcs, it turned out we'd need massive ring beams (1200mm and 1700mm wide and 400mm deep in places) as well as loads of steel. It was all because of the limits of the EPS300. The option of making the entire raft with eps300 was silly money, £11k I think. If you are doing a concrete build (ICF or block, with concrete floors) over 1.5 stories you might find that a traditional raft will work out simpler and cheaper. Our design now is a simple 200mm thick raft (250mm at edges) with only one layer of mesh, so much faster and cheaper to build. We'll then have 150mm insulation and 100mm screed. Don't get me wrong, an insulated raft is a great idea, just be aware of the limits of loading onto EPS. Be wary of the insulation form people saying it's a simple matter of a xxxmm thick raft and a bit of steel...

Plywood is definitely the most rigid. I use structural softwood ply all the time for little bits of furniture. Door panels will be a lot more rigid and light if you use ply sheets bounded by a thicker pine frame. But that's a whole load more effort.

We have similar in water industry - different locks and systems within compounds. It's to stop people getting to areas they shouldn't, E.g. you might have somebody authorised to access a site to deliver materials or check equipment at ground level... But not access heights or confined spaces. This is why you have another level of access protection in place, you can't trust your employees or contractors to be sensible. And this comes from somebody who likes to climb to top of water towers lol. To @eandg you don't specifically need to use security fencing, our site is bounded by a thick hedge on three sides and river on fourth, the broker was happy enough for this to constitute site integrity. Basically you need enough for somebody wandering off and walking on to your site. Block off any holes in hedges or fences with panels, and the main access point any that will be more than enough. I only needed three panels at £22 each and three feet blocks. All delivered for less than £100 so pretty small change in the grand scheme of things. Already have a plan for the panels after the build as growing supports in my veg garden.

Well, if that's a shared access up to the point where it meets your neighbours driveway, then yes, it is a highway, and the fence is adjacent to it, meaning planning would be required. I don't think the fact that it is private matters in this context (not in my experience, bit regions vary). I had similar query at my old house, I got clarification on whether the alleyway to our rear was a highway. They decided no, as there was no vehicular ROW established along it. In my experience, if nobody complains, it'll be grand...

My neighbour who designs and installs MVHRs, says aim for 50% normal operating range. Feels the building reg values are far too low. But, if I followed his recommendation I'd need two 300mh3 units for my 300m² build.... So that's not happening!

Agreed. @Jeremy Harris was actively cooling his house the other day (Wiltshire?) and we had our heating on (Belfast). But from those U values, space heating demands will be absolutely minimal. Hot water will be a bigger energy demand. I might wing it with off peak immersion heating of water and just have UFH loops for a future ASHP if it's ever required. I'll also get a gas connection put in (usually free here as long as have an appliance e.g. hob, tumble drier etc) to make resale easier.

Of course. The air coming in would still be laden with moisture, especially where we are in the coast. You're right, one of those water to air copper coil things in a duct would be an easier and more effective solution. There will be a utility room adjacent so getting a condensate drain sorted will be easy.

That would be perfect, I'd be happy with 10c in summer. I'd be installing a single room MVHR to mitigate condensation in the summer. The MVHR would also do the cooling duties in winter. Though I'd need think a bit more about that.

Thanks to insights like this, we're moving away from the traditional over head bris soleil design to something that will provide low sun shading if required. Currently thinking a retractable sail design, anchored from roof above main window to lower level on the outshoot to the SE. Back to topic: roughly how cool could you get a 100mm screed slab down to in a small (4x4m), highly insulated room with a standard UFH loop and ASHP? Is it just like calculating heating load etc but you just invert the temperatures?

We're going to do something similar in our basement in the NE corner. Full insulated with 150mm PIR and a sealed door. Only need to keep it around 10-12c. In winter time that will be achieved with ventilation, like a traditional draft larder. In summer, I'm hoping we can use the UFH (maybe even loops in the walls?) on cooling mode once every few days or so to keep the temp in that range. I might put in a provision for piping for a single Aircon unit like @Jeremy Harris did for his bedroom, Just in case slab and wall cooling isn't enough, but I doubt that will be needed as we won't need it cool enough for meat or dairy.

Yes. You will need to know: Desired flow rate at the outlet. Diameter of pipework - make sure you use internal bore. Length of pipework. Chose your metric. In water networks, we use litres per second. In your case, litres per minute are a better starting poimt. Then enter your data here: http://www.calculatoredge.com/mech/pipeline velocity.htm Then think back to school and calculate the time it'll take over your given length. You'll find that halving the pipe diameter will result in the time reducing by a factor of alomost 4.

@Tom is upgrading access at this stage an option? E.g widening where possible, drainage works, levelling off. By the sounds of it you're going to have to improve access for construction anyway - concrete and stone deliveries etc. Will make life easier all round by throwing a few grand on a few dozen loads of stone and widening works.

Loved Fred! Such passion for all things suity, rusty and steamy. That was chimney no.3 to come down. The best thing is the bricks are coming down pretty much undamaged and separated as the old lime mortar is so weak. Almost clean enough to stick straight on a pallet and sell.

Unexpected consequence of Corona Virus - you need your 8.5 month pregnant partner to help you pull the house down as all the hire places are closed and you need a long chain and a VW golf in lieu of a telehandler... VID-20200328-WA0006.mp4

Take a look at insulating screeds. You could put down 70mm PIR then insulating screeds on top to give you your floor ready to finish.

The installation manual will specify... From what I've seen from Mitsubishi etc, all seem to have 22mm connections. Yes, fully insulate the full pipe runs.

They look perfect. About €12-€14k for exactly what I need. We'd be quids in Vs renting in 15months. Concern would be if they stop manufacturing before I need it...