Dreadnaught

@Post and beam, I have used that manifold on the supply side of my system (on the return-side, I use a smaller Ubbink manifold). These manifolds come with sound attenuation sponge pads that are inserted inside. Before the manifolds, on the larger diameter ducting (160mm Aerfoam) connection to the appliance, I have in-line flexible sound attenuator on both supply and extract. My system is effectively silent from the bedrooms. It is performing very well.

3.1m x 1.3m. Feels generous. One end has MVHR. The other end has cylinder and heat-pump internal bits. Will use some of the space for storage with wheeled shelving units which I will push around as needed and even remove if I need to access something big. A flexible space. (Personally I wouldn't put any type of house battery inside the house. Precautionary principle.)

In case anyone else is not familiar with "VDI 2035", as I wasn't, this is a good quick intro… https://www.heatgeek.com/heating-water-treatment-explained-vdi-2035/

Very interesting. How is the filter fitted? Do you just remove the valve and the filter wedges between the valve and the valve adapter? With my Ubbink/Brink system, the valves are quite difficult to remove once fitted. Is that a problem for you when changing the cone filter? Are these the cones… https://www.aliexpress.com/item/1005006704266648.html

Hi @Barnboy, I am afraid I don't know, sorry. This is my one… https://underfloorparts.co.uk/product/ivar-uni-mix-underfloor-heating-ufh-pump-mixing-kit-underfloor-heating-manifold-control-unimix/

Of any interest? Still available.

I wonder, are there prescribed widths or depths for a channel so as not to need to de-rate an electrical cable for being inside insulation? Nice video.

The owner of the team who poured my concrete raft was well known to be wealthy from his trade with properties owned abroad. One of his team was originally a chippie. He eventually left to join a team of small-scale house builders. Within a a few months he had convinced his new colleagues to down tools and take up concrete pouring as a means to make much more money.

(A few other disadvantages of pocket doors: (i) they tend to negate the acoustic insulation in the wall that is the pocket; (ii) they are slow and more cumbersome to operate, so better suited for occasional use.)

Welcome @G and J. I am across the border in Cambridgeshire and have a brother soon to be rebuilding anew in Suffolk near Beccles.

For peace of mind, personally I would want the intake up-wind unless the separation was say 3m or more. I would not be too concerned about duct resistance assuming you're using big fat ducts. My MVHR uses external insulated Ubbink foam ducting that is 160mm internal diameter (190mm external diameter), which is comparably huge. The resistance is such ducts, which falls by the square of the diameter, is quite low. I roughly calculated the internal flow rate within those ducts in my case to be 1.9 m/s (2.1 m/s on boost) which I considered acceptably low and should not cause problems of either pressure-drop or noise. You could do a similar calculation.

Best to put the intake upwind from the exhaust relative to the prevailing wind direction for your location (usually westerly in the UK). And ensure the intake and exhaust are both on the same building elevation to ensure even wind pressure between them. Separation: I would suggest 1.5 lateral metres minimum if you can.

@OwenF , ceiling mounted solution: no. I redesigned the kitchen and have moved the hob off the island, which makes an extractor much easier to design. I will be building it within the next 6-months. If I had kept it on the island, I would have chosen a downdraft extractor, albeit I think they are flawed in terms of effectiveness given that hot gases rise and fast.

MVHR: ensure the intake and exhaust are on the same face of the building so they are exposed to even wind pressure.

Can you find a similar door or window which is PAS24 and is similar, provide that certificate to your building control officer while explaining that your manufacturer no longer exists. I had an issue with a window being larger than the size that was PAS 24 certified by the manufacturer, and so in the strictest sense lacked PAS 24 compliance. I provided a copy of the PAS 24 certificate for the assessed size and explained the situation. My local-council's building control then said it was fine.

Timely post for me. Reinforces my idea to double-up the heating in my place under construction; am at first fix. I have wet UFH and am planning to install electric-mat UFH too on my two bathrooms, probably under LVT flooring.

I have screw piles and was advised when doing mine that this form of piling (as it does not remove any soil as such) did not trigger the Party Wall Act. My piles produced almost no vibration so it sounds like yours are not screw piles. And if yours are not then there is a good chance (as described by others above) that the type of pile that your neighbour is using may well fall under the Party Wall Act. In which case you would have plenty of powers to respond.

@HughF, that's interesting. Do you know the approximate volume of your system? Mine will be about 95 litres. It will be a similar open-loop system to the ones in this thread.

Yes, rather concerning. The "Mira Flight" tray comes in a few different forms. I was intending to buy this version below. But am now unsure. Such poor basic quality control is rather damning. Source: https://www.screwfix.com/p/mira-flight-level-safe-rectangular-shower-tray-white-1200mm-x-900mm-x-25mm/250hr

… and cooling. Often summer cooling is a greater challenge for a passive house than winter heating.

My guess is that… You should pay VAT on the hardcore that you buy but only if you're buying from a VAT-registered entity. You would then claim it back at the end of the build if you qualify for the "DIY Housebuilders’ scheme". The crusher man is correct in charge you 0% VAT on his services (including his machine, which he operates) as that counts as site labour. … only a guess.

I have a mono-bloc so no F-gas certification needed. I might guess without evidence that the majority of domestic installs are mono-blocs. If you want a career in heat pumps, is F-gas certification really needed. Could the Heat-Geeks course, or similar, be a better route in to the industry. Utterly ignorant so I could be missing the mark. Just my tuppence worth.

Back in 2022, I was charged by Latzel €20.83 on a £500 order so sounds plausible.

Thanks @nod. Makes sense. Very helpful. Thanks all!

Thanks @TonyT. Good to hear. My decision has also been helped by when I saw the price difference for "full-pallet-only" specials compared to the lines held in-stock. Nothing dampens my perfectionism more than being asked to pay a *lot* extra to achieve it