Nickfromwales

Fabric heat loss is dealt with by insulation / doors & windows etc, and ventilation heat loss is dealt with by arresting a) infiltration ( drafts ) and b) convection heat loss; loads of house builders / frame suppliers seem to not give this their full attention when detailing this at the roof level forgetting that heat rises . If you have poor ventilation heat loss measures ( eg not going to a very good / excellent ( not just 'good' )) level of airtightness, then all the insulation in the world will amount to zilch tbh as the saved heat will just escape to the clouds, whilst pulling lots of fresh, damp and cold air back in to replace it 'Excellent' airtightness will mean you could install lesser amounts of insulation ( eg build to our current and shitty building regs equivalent ) and you'll still have a very high-performance dwelling as a result. I would focus all my energy and efforts in the pursuit of the best AT score you can get you mits on, and once you are already 'in to' the installation of AT tapes and membranes, it will ONLY need you keeping a close eye on attention to detail and no stone being left unturned to take you to the 'excellent' result. Do not dismiss the value of putting in just a little more effort with this, as, if you're staying in the house long-term, the rewards ( lower running costs and personal comfort ) will be significant. You absolutely need a definitive statement regarding method of execution / target ACH score etc ( before parting with any money ) as a lot of lesser interested TF suppliers pay this lip-service only, and that's on a good day...... Ask for details for sections where tapes / membranes start / finish etc and what happens at wall / slab junction plus doors and windows etc. If they start squirming, it's time to move on to another frame supplier.

+1 Good to know, thanks!

I cannot think of a reason to reinvent the wheel here tbh, and as long as there is a thermal break ( with one course of aerated ) then you're as good as it needs to be afic. Is this in motion yet / or still a blank canvass?

You'd have to Tigo the lot most probably. FYI you can get Tigo's which go 1 unit per 2x panels, so may help out with economics, understanding their correct deployment of these units is of course critical. Prob have to re-string also with that close a capacity vs what will end up installed, to split evenly across the two inputs.

Indeed. Domestic systems should ( IMO ) START at 10,000L minimum capacity, and only then would I EVER be an advocate of installing such a system. Even more prominent when my clients state that they are keen gardeners, have large grounds to jet-wash / water / lots of facades which they know will need regular cleaning etc.

I'm just stating the facts. Installing more PV should only be done if you are at sub zero export, eg still ( residually ) reliant on importing from the grid after the first installation. Installing specifically to export is the least "helpful" thing you could possibly be doing with your money. Why not invest in installing IWI or EWI / insulating cavities / replacing boiler with a modern appliance & controls / upgrade to 3g glazing etc etc. If you really want to help the planet, donate the funds to the WWF / other such entity that will put it to good use. You're not doing that afaic, sorry. If, however, you go for a hybrid inverter and add batteries, ( so you do not need permission from the DNO ( as the battery system adds to your gross microgeneration figures for submission to the DNO )) then this may make sense. I would dare to say that you'd still be better off, at that point, in investing in a bigger battery ( instead of the additional PV ) and load-shifting off a ToU tariff to reduce reliance throughout the entirety of the year. I wouldn't be an advocate of just installing a battery for this purpose, but if it can be quickly and cost-effectively installed, to primarily harvest the export you already have, then it's a more viable consideration to do as I suggest above.

Yup, noted earlier that there is no insulation ( and expansion ) upstand around the perimeter of the heated slab ( screed ). Needs a bit more detailing before we allow this to proceed

It is a contradiction to install additional PV that you won't use, so referring to not being able to give away ( for SFA ) the extra energy you pay ( a disproportionally huge amount ) to install is lunacy. If you're getting the FiT payments ( a bloody grotesque scheme on a good day but staggeringly good news to anyone who adopted it ) then just leave this all well alone and enjoy the free money? The planet will not benefit, due to the processes to manufacture, install, and recycle these components. This plan is ( IMHO ) a bad, and wasteful, idea.

If it was my house, I'd do both. Comfort temps for the floor vs having to heat the spaces with it ( so UFH just providing some uplift ) and 'decorative' rads providing the grunt.

You only need to meet this criteria if you export the extra ( new ) capacity. Why not fit a hybrid inverter, totally DIY it, and set the inverter to 0% export via limitation software? You only need an electrician then who's done PV before.

Ouch...

Use this opportunity to install more insulation into the floor, and more screed, for an all-round better performing heating system ( assuming UFH )? For inverts for drainage you should be referencing TOC ( top of concrete ) not FFL . TOC for you would be top of screed.

You can install acoustic baffles, such as angled timber sections ( al-la louvred door type design ) which have gaps between the 'blades', and even clad those with faux or living greenery to further absorb / dissipate the sound. FYI, a Panasonic HP, which I installed for clients living in a tightly-packed urban setting, was very quiet indeed. With the next door neighbour stood less than 1m away from it, whilst it was gong full wallop ( 47oC flow at that time as I was commissioning it ), she stated that it simply could not be heard running / operating. The only obvious sound ( not noise ) was from the fan, which could only be heard when stood directly in front of the unit, and at less than 5m away from it. This was in a very low energy requirement dwelling, and if the heat load had been much higher the results would have been different. You'd need to fully understand these variables to ascertain the resultant sound emission, as the operational conditions will be a huge influence on the outcome.

You CAN put UFH in this area, but it would be expensive to run eg if this is a basic building regs property ( or worse ). Where the original floor is you could consider oversized radiators there, and then just install UFH in the new area for comfort heating. You can run the overlay system throughout, but it's the very worst type of UFH out there. Another big influencer is what you then lay over it, with tiles being better, wooden flooring being worse.

Hi. MBC TF have this down to as fine an art as anyone can expect. They’ve had their bumps in the road, as have a few, but on the whole a good company with a very good product in my own opinion. I have zero affiliation with them, but would gladly speak highly of them to you. If you wish to see their projects just ask the reps ( Keith or Lee are extremely helpful ) and go see for yourself. They offer a tour of the factory too, so you can see what you’ll be getting for your money. 👍 Other TF companies are available, but ( by coincidence ) I have worked on / been around a lot of MBC builds vs any other supplier. Do your research and measure twice at least!

@TerryE Hope Jan has a speedy recovery!

Nope, lol. In times of drought you’d have used it up before you knew you needed it. Actually, it would be a 1/3 full with potable water ( then rendered cat5 ) where the top up had already occurred because of the lack of rain. I quite liked the idea, but stopped my clients spending their money as it just doesn’t add up on paper, unless installing at least 10,000L of storage. Then I’d buy the cheapest pile-o-shart pump I could stoop to, and hope it lives as long as possible 😛

Just type “rainwater” and “RWH” into the search engine and there’s loads to read here about this subject As said, by myself and others, buy more PV!! In 10 years time you’ll be kicking yourself that you didn’t. Cost of electricity then will be the concern, plus guess what the RWH pump runs on……

This is more about having something which COSTS money vs saves it. You need a kitchen, RWH is a trinket.

🤢🤮

Likewise lol. Guy came out, replaced the entire guts of the machine under warranty, scowled at me a good few times muttering "idiot should have been charged for this", and handed me the bolts saying"you said you were a plumber, mate?". Thing shook itself to death over a 10 day period before committing Harakiri. In my defense, that was the first WM I had ever owned, and I was a very young plumber lol. @Kevin77 Is the unit mounted with flexible hoses, or directly plumbed to rigid pipe?

Assuming nothing was shed from your body during the bath ?? eg the reason you got into it in the first place

Yup.

Takes 3x more scrubbing then, and that uses more hot water...

Not for the rest of the population they're not...... 😜 That's exclusive to you matey.