JohnMo

Battery storage may have an alternative technology on its way - the flywheel. https://www.pv-magazine.com/2022/02/24/french-flywheel-storage-system-specialist-secures-e10-million-investment/ Funny thing I did a a project paper on this subject 30 years ago. There was even a Le Mans race car with one installed in the early 90s and trams have had them installed for energy recovery and storage. Run a flywheel on magnetic bearings and in a vacuum, nearly no standing losses. Use a magnetic clutch to engage a motor/generator for power output and power input. It's not rocket science as they say, just some kenetic energy.

I would explore if you really need to up the size of the heat pump, as the heat downstairs will go a long way to fulfill the heating requirements of that space. Simplify the glazing design or don't install any, will help with the heat losses. Do you need a spandrel panel, could it stick built on site?

Good places for info are the German passivhaus website, lots of good info freely available. You can build a good building using any build method, the important bit is the contractor being good, because many will not read detailed notes and just do what they have always done, which may not be what you want. The other thing is constructibility, so PIR in cavity may not be the way to go as it's too unforgiving. A lower performance u value, may be better than a high performance u value badly installed. So Rockwool or bonded beads etc. Form factor makes a difference, but only in respect to how much insulation you have to add to meet the 10W/m2 criteria. We followed the principles, getting rid of thermal bridges, continuity of insulation, high performance triple glazed, airtightness etc. Our form factor is at the wrong end of the scale, long thin and single storey, all insulation at roof line. But so far this heating season our gas input has equated to 13W/m2 (NE Scotland), that includes, a prolonged period of the boiler short cycling, drying the building out etc. All in all pleased with the result. Get the architect drawings and a highlighter. Get each cross section and starting at a piece of insulation, follow its path around the building, up the walls, roof, back down the wall and through the floor, your highlighted light should have no gaps. Any gaps rectify. Ask yourself could I install easily, example, our architect haf mineral wood and PIR insulation in the roof, I changed it, to counter battens (to increase fill depth) and full fill spray foam. Good luck

Suppose the first question is did you get single quote or multiple. We have Posi rafter (about 250m2 floor area) and our garage (60m2 floor area) has normal ones both came Pasquale in Inverness neither were too much of a shock price wise. Pasquale redid all the structural calcs, sent them to the structural engineer to approve. Which he did. I've not done anything more than that. Our original roof trusses on the house were all in 250x45 solid wood and that was super expensive. Both materials and labour.

Does sound expensive. Who is giving you this cost and is there an option to use someone else to remove it

Is that a photo after or before applying? Looks like before. I would apply it with a soft natural bristle brush, (12 to 14 inch) with the right mix there should be nothing to brush off.

Thought it may be...

Triple aim for 0.8 on an opening window, for the whole window not the glazing. Double 1.2, but they are difficult to find. Ask for full u value calcs before you agree to buy, as many salesmen try to talk glazing u value, not whole window.

Lesson learned, agree prices before approving a changes, they always cost more than you expect.

Don't have a continuous insulation layer - wrong, it is thermal bridge free, the continuous woodcrete thickness and the mix material layer (woodcrete, PIR and concrete) have the same thermal resistance. U value of 0.14, thermal bridge free out the box. Block dimensions are acceptable to get a straight vertical wall Funny that the lattice work concrete/woodcrete doesn't require the same amount of rebar required for a polystyrene block. The porous nature allows a high slump concrete mix, which can settle more easily without air pockets, the porous nature allowing the concrete to dewater. Funny how leaky the blocks are, never had any water in the house after the roof went in. Behind timber cladding you have a breathable membrane, same as most buildings. Stone slips directly bonded to woodcrete keep other water out. And the porous nature of the block is vapour open, for a breathable building.

Yes you use scaffold, the same scaffold as you will need to erect to allow the roof structure and covering to be installed. So scaffold up, do final rows of blocks, pour, move on to roof.

Still don't understand the hate people seem to have for Durisol. Other than 12mm OSB screwed (directly into the woodcrete) at corners, lintels and cut blocks, that's the only bracing you need. No blow out on my build or two other I know about near me. Easy enough to do yourself, without a lorry load of bracing other systems seem to demand. Durisol has been around for 70 to 80 years, tried tested and worked easily enough for me. A downside is it's not airtight, so that's an extra job to do, but it is vapour open and can give a breathable building.

Isn't that what mvhr does already, although did loose the will to live reading the link

I have seen this may worth looking at https://m.sessile-oak.co.uk/Resources/Glazing There is a thread on here that looked, had a design, so may be worth a search. Don't know any of the answers, but aware how unforgiving glass is. Linear expansion coefficient is what you are looking at. If you have a gap around the window at zero degrees, with the sun shine on the wall and the window, glass will expand so will the wall, closing gaps, you need enough space between the different pieces so they don't end up breaking the glass. https://www.google.co.uk/amp/s/www.engineeringtoolbox.com/amp/linear-expansion-coefficients-d_95.html

Sharp sand, grass likes the extra drainage, moss hates because it irritates them, so they don't grow. I think you need to use horticultural instead of builders Sharp sand.

Weather compensation, heating optimization start/stop thermostat, waste water heat recovery unit under a shower, more insulation, better window u value

Some basic questions Have you checked you have allowed enough room for the glass thermal expansion and any settling of building at sides, bottom and top of glazing. Do you need a weeping hole at bottom to prevent any water accumulation? All you sizing looks tight for easy assembly, the rubber glued to the glazing may cause hang ups when trying to insert in to block work.

Or larger b&q off the shelf range, you pick it of the shelf and know if it's all there.

Granted, that's why I have a filter on the extract to the MVHR. dMEV units can be removed from the wall or cleaned in situ. A MEV unit would also benefit having a filter in the extract of the kitchen

Resurrection of an old thread, could the water be run through a heat exchanger and used to heat or preheat DHW? So instead of taking fresh water and dumping it, provide a closed loop recovery system? Any thoughts?

After about year and being self insured, I think the cost may be down to you. But check the solar company warranty etc.

I would just install a dMEV fan. These run all the time at a low flow rate and are almost silent. Something like a vent axia, would do the job. A decent electric towel rad, on timer thermostat, would do the heating.

We have Sansfil also. Should only be installed by qualified person, which is a plus. Use exterior grade 18mm ply instead of OSB. Sanafil sits on a flease and is screwed on to the ply with spreader plates and the overlapping seam, which covers the screws is hot air welded. Standing seams are then welded to the membrane, set the spacing so a standing seam covers any joints. Our roof is 12 degs so you will see the effect.

Try finding a a wet plasterer in NE Scotland, hens teeth, when you do find they are too busy. Plasterboard and Ames taping is the norm around us. So wet plaster was a non starter for us.

Parge coat. 25kg cement, 75kg builders sand, 3 shovels hydrated lime. Enough water to give double cream consistency.