Nickfromwales

Membrane can go atop the 60mm PIR and be fixed by the battens. After that 1st fix electrics / plumbing. The OSB would be affixed AFTER 1st fix, so all metal back boxes would be in already and the OSB cut out to suit. Sounds like a good plan IMO, and AT detailing with a membrane behind the battens is shit-loads easier to manage and preserve IMHO.

Render IS waterproof, which is why it gets applied! Yes, point impact would damage this with relative ease, but you can apply additional layers of base coat and mesh to 'beef' this up. If you want to take a hammer to it, not much will withstand that tbh, but render over a cement board would be an option. Visit a house with render over EPS EWI and see for yourself that it is quite robust. If you are crap at parking and hit the corner of the house........use the bus

Wow! That's not exactly discreet Moving parts and maintenance? Lifespan? And why not batteries?

Is it electrical energy you wish to convert / store?

Some useful numbers here https://cordek.com/products/filcor

The Nudura is from 'across the pond' so as @Russell griffiths found out, the embedded plastic spines are on imperial centres. To affix plasterboards at 1200x2400 you would need to apply horizontal counter battens rising on 300 / 400 / 600 OC's ( which also creates your service void if you don't want to bury cables flush into the EPS in conduit ) or you could fit 11 or 15mm OSB ( 1220 x 2440 ) and PB to that.

As one of our original boffins once noted here, plasterboard actually has a very high specific heat capacity, so not quite cut and dry.

I suppose I should add that I found myself, a few days back, wondering about exactly how much wasted ( diverted ) energy would be spent maintaining a "passive" dwelling that had not been designed with some degree of management for unwanted / nuisance solar. I believe it would be significant, eg a shameful waste. Even having excess PV going into that endeavour seems a little grotesque from a design PoV, and it should, instead, be going into other strategic energy storage for self consumption. "Fabric first" as always, wins the day.

Thanks, and agreed. My ethos is prevention vs cure, so where some designers will give you the option to go 'full throttle' to cool a home, I prefer to simply work on preventative methods to stop it getting hot in the first place. With successful management ( by using controls with a tight hysteresis ) the runaway should never be more than a degree or degree and a half, eg the uplift over the time taken for the controls to recognise that occurrence and for the system components to have kicked in to respond to tackle said unwanted uplift. A correctly designed system, in a relatively relaxed state, should not struggle to bring that back down in a reasonable timeframe without having to become too aggressive in its response. To cool a house down that has been left to runaway to, say, 24oC would almost need air con to drag it back down, given that by then the fabric surroundings would have had time to achieve that new ambient and would be holding on to that heat energy for a much longer / extended period of time, ergo the 'response' would need to dialled up then from a whisper to a shout. Each dwelling / instance is different, so I review each case uniquely, and on its own merit, in my day to day business. Comments here, however, do sometimes generalise a little, but it is a widely differing crowd on here with varying dwellings / installed systems / wants / needs, so we do our best to cater for all.

Did he let out any outbuildings and the extras are landlord meters eg outgoing not incoming?

Interesting. My main thoughts are if the supply air is branched over two floors and the Comfopost is supposed to deliver 'some' heat or cool effect, then surely the main unit would have to go into a semi or full boost flow rate to facilitate that? If the upper floor was the one needing the extra help, then the whole house would receive additional airflow whilst the upper floor was serviced, as trying to shift any kind of heat energy via MVHR would be utterly useless at 'trickle' flow rate? How were you 'sold' this idea?

These do appear to be the main flaws, vs more uniform blocks like EPS systems. Woodcrete deffo needs a fair bit of putting right before external render can be directly applied, and it's deffo a good idea to parge all internal walls and dot'n'dab if you want a really good airtightness score plus level flat walls with 'minimum' fuss. Even 5-10mm out requires a lot of residual work, but that does happen with the EPS systems too, like Nudura ( only named because I've been working in a build with this system so can speak from direct experience ), but the EPS can simply be surformed, like the EWI installers do, to quickly get a nice flat surface. EPS wins imho because it's non hygroscopic, and is probably what I would build with, that or twin-wall cellulose blown TF.

🙄

Nonsense!!! My mates lasted a little over 6 months ........ .........we're both going to hell btw.

Reliance are very good bits of kit.

185mm gross is a healthy amount of PIR, so I would stick with this tbh. Now I see the 60mm internally the concern of cold bridging from the frame is dealt with. Don't apply to the outside, as others have said, as it will unnecessarily complicate things ( with little reward imo ). Looks good as-is.

Use plywood cut down into a strip instead of natural timber. That won't split when you drive 2 screws in in very close proximity.

Still bewildered as to why anyone would remove all the service space within the posi-joists, but it's down to what each person sees is of value to them I suppose. Why showing no solar on the front roof? Architectural typo? With a swimming pool I'd be grabbing every ounce of 'free' energy tbh. Are you insulating outside the concrete core of the substructure and then again internally where the pool is?

All ICF systems hold the concrete core at 'arms length' with it being locked into the centre / core. "Thermal mass", as it has been nicknamed, would then exist in the floor and internal volume vs the fundamental walls themselves. It doesn't really matter tbh as all of the popular build systems typically end up clad internally in plasterboard, which actually has a very high 'heat capacity'. Thermal mass is this heat capacity, eg a surface or materials ability to absorb, retain, and transmit heat energy to assist in maintaining an equal / ambient temperature balance. I'd choose ICF over a TF with a PIR core any day as it offers a lot more decrement delay, but the hands-down winner ( IMHO ) is a cellulose blown frame. After being in so many of these in varying states, eg from start of build through to occupation, that's what I would choose for my own house ( when I finally finish doing this for 3rd party's and do my own build that is ). An ICF system could only really offer up its "thermal mass" if the concrete core was uninsulated internally and you wet ( plaster ) coated that for your finish, so this subject is utterly irrelevant afaic.

Bonjour, as we say in Wales. Welcome aboard. You'll be a welcome feather in the BH cap

Hi. If you want an optimum design for off-griddyness then I would suggest a dual cylinder arrangement. A 500L TS ( thermal store ) with 2x 3kW immersions, and a 300L UVC ( unvented hot water cylinder ) also with 2 immersions, with the TS preheating the cold feed to the UVC. This will massively increase your potential to store energy as heat, plus the TS can be depleted ( for heating ) without sapping all of your DHW for bathing. All excess electrical energy into the UVC first, then cascading to the TS. Batteries and PV can dump into either on demand, whichever needs a nudge. Another advantage is, if you have a diesel genny which is water-cooled you can divert the heated water from that into a low mounted coil in the TS to absorb every ounce of energy you create, wherever it gets created. When you have the least solar revenue it will be the winter, and you'll be needing heating, plus the batteries will need topping up via the genny, so, one problem gets solved and the bi-product ( wasted heat from the genny running ) helps to solve another by using even low grade heat at start up to the high grade heat after it's been running for a while. Zero is wasted. What are you doing in terms of heat emitter? Concrete slab with UFH to be used as a further energy store?

Anti-scald mitigation is a core safety remit, and BRegs requirement, so how do you tick that box with <46oC at the bath when turned to max hot temp?

Reference above to a conclusion drawn……was irrelevant as that chap was NOT off grid. Anyhoo.

ICF floors need a massive amount of support during, and a couple of weeks after the pour. Do you plan 1st floor UFH?

You buy a 22mm one and then replace the metric olive with a 3/4” olive @Russell griffiths would have known that if he wasn’t busy touching fish inappropriately. Or, just one of these ; https://www.screwfix.com/p/flomasta-compression-equal-couplers-22mm-2-pack/66818?_requestid=344691 with one of the olives changed out for one of these; https://www.bes.co.uk/3-4in-compression-olive-copper-21062/