RichardL

Have you got a remote bathroom somewhere with its own local water heater? It would only fire up when the water cools or someone uses a tap.

Theres a ledge/cill to go in the outside surely although the window would sit on that normally - have they measured for a cill and not fitting it?

This - for now... If the batteries are charging they're not discharging and if yesterday was sunny then overnight they'll have some residual to reduce the overnight top up. Keeping an eye on the overall draw from the grid with batteries/immersion and car all pulling at the same time. I still think a time of day based system is simpler than relying on layers external infrastructure/cloud to be up and talking to each other, You just have to look at solis inverter forums for the regular changes/breaks and downtime on their offering, I suspect others are similar or at least out of the consumer's control? I can only offer it IS possible to keep it simple - for the moment.

Is your EV sitting in the drive when the sun is shining? I found it easier to charge the car on the known off peak overnight, along with water heating and let the PV/Batteries time shift some of that off peak to run the house. Granted it depends how much PV you have and if the car is there when the sun is shining vs. a work destination. Not yet bought into the over complex cloud solutions/integration.

Certainly air leakage - its not obviously drafty inside, but in the floor space and loft space theres no issue with ventilation - eaves seem to let air through to both areas relatively freely.

Around 1' -18" thick.. outside - stone facing cement/roughcast render, from what I saw when re-tiling I suspect rubble infill. The bedrooms sit half in the roof space, both have a gable end wall / end of the house.

Hi - looking for pointers: I have a couple of rooms in a solid stone walls part of the house with 2x and 3x external walls respectively, one has the inside of the chimney stack. I can keep them warm if I push in enough energy - but overnight in winter they drop back to 12ºC at the drop of a hat. Room floor sizes ~3m x 3m I have external insulation elsewhere but it's not possible/desirable for this part of the house so thinking internal insulation. Ceilings above to loft are insulated. Question Is IWI a potential DIY job - battens/insulation materials followed by a professional to skim/plaster? Drilling/cutting boards etc I can do. Can anyone recommend any products to shortlist - especially thin as possible options, any build up needs to be <10cm per wall or I'm stealing a lot of internal space. Many thanks;

Re the water - makes sense, Go for a fixed short glass screen - perhaps 30cm then shower curtain. The fixed screen isn't too deep so you can still get to the taps & catches most of the water, didn't go for a hinged screen re leaks (to your points), just a curtain that hangs inside the tub. e.g. this was the bathroom from our old house with a Bette Set tub, that room was probably about 2m x 2m, Loo is on the left outside shot. Boxing in is to hide pipes & match the window cill - the LHS was an outside wall. After refurb ~2006 After real life use when we sold the house ~2017 For fun - this is the before picture - nice corner tub in green with gold taps & carpet... is that retro cool yet ? After living with the corner bath for a year or so - they're super uncomfortable!

+1 for the shower/bath... Bette used to make nice shaped square one end/flat bottom tubs. In a smaller bathroom I went for a square ended steel bath and shower at one end of it rather than squeezing in a shower cubicle. There's no substitute for space giving that feel of a little luxury vs. too much stuff.

What do you actually 'need' in a power-cut, Understood - depends on your local situation - how often you get them and how long for etc.. Freezers will last a fair while if sensible about opening them, Cooking can be put off usually until power comes back/live on cold snacks .... Think it through and work out if a full blown house disconnect and backup is worth it, vs (in my case) an off the shelf UPS which keeps the internet router up for work for a couple of hours and laptop/phone batteries maintaining a similar uptime. Medical equipment accepted - I'd assume that sort of kit has its own local backup option rather than relying on a whole house/site solution?

Consider a new back to the cupboard to hide most of it, removable inside, it looks like most of it would be behind the old back-wall of the cabinet. Assuming the plumbing is functional.

+1 THIS, now is the time to overthink things, make lists & decisions - sleep on them - and re-visit and simplify a few times before finalising. It's going to be much cheaper now than after contractors are on board.

External wall insulation on timber frame I can recommend, it transformed part of our house into a space that could actually keep heat inside vs. before the upgrade it just wouldn't go above 15ºC in the winter no matter how much heating was on! I would even go so far to recommend the firm we used in Blackwood, South Wales - for the EWI only though which they do themselves and pretty good job. (Take care if they sub-contract any part of the job) https://eliterenderingsystems.co.uk

That works - much better than measure everything guess materials - for existing builds. IMO you'd have a much better chance of a. making that work with installers, b. be understandable by the customer - than the current standard approach. I don't doubt the latter (measure heat loss & calc sizes etc) works - it needs work on making it transparent and be seen to be working.

I don't know - seems part of the problem is a mistrust, or can't be bothered/afford to learn, or can't measure accurately heating requirements using the extrapolate from materials/rooms sizes etc method. For whatever reason that approach (fabric measuring) wasn't used on pre-heat pump sizing - the trades/installers - just scaled up to make sure there was enough. Just because heat pumps amplify the rule-of-thumb & experience methodology is not good enough - that on its own won't drive change before the heat pumps get a bad name for themselves (already happened) A rule of thumb method - even the controlled test Tech.Connections did may work better to ramp up use of heat pumps? I don't think I'm a luddite re methodology - just looking at what happens on the ground. Post-note - you could regulation the heck out of it and try and make that regulation mandatory (see MCS) - That doesn't tend to solve the problem though - I suspect it needs a simpler rule of thumb/sizing methodology.