Nickfromwales

22mm cement board would do it nicely. Such as Link.

Oops. Read as thermalite. Been working with these for the last 3 weeks so now brain-numbed. I’ll go kneel on some pencils.

Not sure if you have a way to monitor the temps of the batteries, but trickle / slow charging is always favourable. I’d say drop the charge rate by 50% and see if that gets them topped up before 05.30. If it doesn’t, just add 5% and go again.

No need to apologise, they’re all grown ups who are just getting their 2 cents out and onto the table. Best to simply ask your chosen architect? It’s their contract that has their unique terms within, so in actuality you should already be in possession of those terms; it should be available to you from day 1, contained within their terms of business and T&C’s?

Yup. So basically you’re at a stage that I refer to as ‘drip dry’, so no point in worrying about that little bit of wet afaic. Wind-driven rain will get into every mm of available space, and capillary action can pull that along a membrane for meters and meters, so is also not truly representative of where you’re currently vulnerable to such ingress. ”Stand down red alert”

Agreed. But easy(er) to say if you’re someone using a TS as a hot water heater exchanger? The pic I shared used one, and they never ‘ran out’ of DHW, so case in point. They had more chance of running out of dynamic flow, than DHW, so I directed a TS capable of still outputting space heating whilst the boiler went full wallop doing max demand DHW without either being compromised. I put a lot of thought into that, and chose a quality gas boiler capable of <4kw when Lilly modulating, or a huge >37kw of heat energy output whenever it was necessary to ‘recharge’ the TS. I don’t think it was grotesquely oversized personally, and the client and his family were fully consulted before any prices were arrived at and kit purchased, with costs know, and expectations understood and met (actually exceeded). Some good words about perceived flow rates and what shower flow rate would (should) be acceptable, and that can bring a lot of the capacity related issues back down to earth. I had that chat and was told to ‘go large’, with the client then making their own fully informed choices. If they’d have insisted on a HP, I’d have walked away, or I’d have had a contract loaded with caveats to protect me for when disappointment kicked in. Sense prevails if the persons involved are sensible, imo.

What stage of weathertight are you?

All quite relevant, to get a practical solution “Continue….”.

Multi tool with a TC blade and a hoover = next to zero dust. Grinder = lots. Multitool will fly through it. A regular bimetal blade for slicing downwards to do the chase after cutting the side channels is deliciously simple and controllable. One hand on tool (ahem) and other on the Henry.

Wouldn’t that mean huge infiltration during winter? The problem is, the time you need the ‘benefit’ is the most detrimental time to use such a system. Retrofit of MVHR has got to be on the table at this point?

Agreed, but won't the PIV be in the attic blowing down into the open landing? Or are you suggesting blowing air from atmosphere into the bedrooms? If the former, the input air will seek out the path of least resistance, eg you can't guarantee it'll solve the bedroom issues. I have 4 kids, so am defo up for taking the £20 prize money on offer.

There are large instantaneous gas water heaters available, eg not boilers. Just zero chance of PV > DHW without some kind of cylinder.

Buy a trickle vent and see if it physically fits at the head of the window. If so, it's just a matter of drilling a series of 10mm holes along the length of the vent, and two more holes for fixing screws. If you are budget shy for new doors and windows, you could maybe install some 4mm neoprene insulation 'tape' both inside and out on the frames, then dress over these with white PVC D section 'makeup' trim, if you're happy to have a DIY improvement at least. Not much more you can do as aluminium (when old style frames which are shockingly bad for bridging cold) is horrid stuff; realistically you need to change the windows / doors etc, as you prob already know.

Not without trickle vents?

Got one on the go (certified PH) in Bow Brickhill, but that’s on stop atm as they ran out of funds. I’ll seek you out when they find the pot of gold they need to get going again….not holding my breath atm though

You get a feel for it. Brass on brass should be assembled with pipe jointing compound, or PTFE (liquid or regular tape). An indicator of it not being tight enough is by it leaking obvs…. Then just a 1/4 turn tweak at a time until it’s not.

My point is, to get anywhere even close to the performance gas, a luxury we’ve become used to, and to have very high kw ratings on tap (without the need to wait for the energy to ramp up) then the options for heat pumps are non cost effective, impractical, and very much not on the table. BTW, I didn’t pick the biggest one to be obtuse, I picked it because that’s the one that stands any chance of matching the performance of a high kw gas appliance. So basically you need a heat pump that’s exactly the size of a small garden shed!! And you need maintenance / service / repair access as per MI’s. Remembering that this thread is being replied to specifically to answer the OP, for which we need to get a result for that unique enquiry, hence generalising about HP’s isn’t of any real relevance here; plenty of ASHP / GSHP chat on here for every other situation. How to get continuous DHW, not from a heat pump; unless you’ve a very big back garden, a spare bedroom for the UVC, and a massive budget.

You won’t. If you were using a kango demolition hammer I’d be slightly worried, but either stitch drilling it or diamond core drilling will be zero detriment.

Probably....but still happy to stay up and argue the toss.

That's "then" and the OP wants "now" solutions?

You lied about your age...you're clearly in your late 70's lol.

If you have 8' x 8' x 5' of space (plus surrounding areas clearances)...... / 4 ELM DIMENSIONS // B C A Unit Elm 75/60kW LN Elm 75/60kW SN Elm 105/70kW LN Height ‘A’ (mm) 2400 Width ‘B’ (mm) 2354 Depth ‘C’ (mm) 1455 Operating Weight (kg) Shipping Weight (kg) 1850

What if the ASHP option cannot provide sufficient oomph, as per the OP's request, then do you steer back to gas regardless due to necessity? Guilty as charged. Send him down.

You said when he 'has to go to ASHP', so I'm charging you with entrapment.

Yes to PTFE, but if easier you can buy liquid PTFE / joint 'glue' and leave these to cure as per the instructions. https://ukradiators.com/products/that-rapid-blu-stuff-liquid-ptfe-tape-50ml?nbt=nb%3Aadwords%3Ax%3A22500772236%3A%3A&nb_adtype=pla&nb_kwd=&nb_ti=&nb_mi=290210051&nb_pc=online&nb_pi=shopify_GB_14870046245237_54875791294837&nb_ppi=&nb_placement=&nb_li_ms=&nb_lp_ms=&nb_fii=&nb_ap=&nb_mt=&tw_source=google&tw_adid=&tw_campaign=22500772236&tw_kwdid=&gad_source=1&gad_campaignid=22500719472&gbraid=0AAAAADoz-xFD0GR_UGIhNwyTm5D5bA2MB&gclid=CjwKCAjwxfjGBhAUEiwAKWPwDpxdLx0vas8vgmw0X3OdlWk7TJTAewnN_f5QFpeBD7OxQ_Slagyi9BoCzPwQAvD_BwE