JohnMo

The person that put the UFH drawing together, has assumed you will be having a fully zoned system, so each space will have a thermostat including the hall. That is why they bunch all the pipes together when transitioning through an area. This where the design comes in not making pretty images. You need to understand the heat output and space heat demand. Areas like the utility can be overheated very easily with so many pipes going through area. You need the so called designer to factor this in to the design - LoopCad will do this for you automatically. LopCad is a free to download and a month or so free to use. A weekend messing with is will have a good design done.

There me thinking people that needed dehumidifiers, really needed to sort out the ventilation - maybe they do? If we dry clothes on an air dryer in the utility, they dry fine, humidity levels bearly change in the house, certainly nothing noticeable.

Just done a search "This has potentially increased since the COVID-19 pandemic (Young et al., 2024), with many people working-from-home in environments with poor mechanical air-ventilation (Naz- aroff, 2021). The proportion of time spent in indoor, CO2 enriched environments could also contribute to the changes in blood chemistry noted in the NHANES data and is an important consideration in interpreting changes over time, and forecasts for the future.

Dehumidifier - not sure it would make our house comfortable at all, it never much above 40% in winter. Stripping more humidity would not make sense. Think a heat pump dryer pulls 3-400W.

But could it equally be increases in house airtightness, coupled with poor ventilation, kids playing less outside, spending too much time inside etc.

Not sure how, neither condenser dryer nor heat pump dryer have an air outlet. Older ones are supposed to have air vent routed outside

I used these inside and out, used hundreds, almost zero issues https://mkm.com/product/47mm-x-50mm-rough-sawn-carcassing-green-treated-t001663 These wood screws https://www.screwfix.com/p/reisser-cutter-tub-pz-countersunk-high-performance-woodscrews-5mm-x-100mm-250-pack/734pv

New invention, we bought ours about 15 years ago.

Not sure if you house layout, but could you add a dMEV fan (high up on an internal wall to push the heat from your hot room to hall way etc.

That's sad, for you, a heat pump dryer is a wonderful thing. Nice soft clothes and towels and next to no energy to do it.

You can get it from Amazon, RS Components, just choose the correct thickness. I choose RS Components so I get a known quality.

Couple of comments - because I can't help myself. 1. You have all loops transiting via what I assume is a hallway, then an additional 3 loops dedicated to the hallway. Deleted the dedicated loops and spread the pipes transiting through halls to provide hall heating. 2. Low temp heating will perform just as well with either spiral or serpentine. 3. Design is done on the premise of zoned heating, using a thermostat to control each area. Bit like adding the largest radiator you can fit on a wall in each room. As it is the floor array isn't designed for room heat loss, so balancing the heating will be battle. 3. Your pantry wants to be cold, I would keep all pipes well away from there by at least 300mm. 4. Assume your manifold is in or close to the utility, with all the loops transiting through that area, it will always be hot in heating season, you do not need a dedicated loop there. You will also need to think about adding insulation to pipes to prevent overheating. So 9mm insulation for the first 2m of each loop or run in 20mm conduit to thermally disconnect from screed for the first couple of meters. 5. Drawing by something selling products, not heating design. It isn't a heating design.

A lot of heat generators in a small area, the 16 loops if not insulated, would make the room hot, battery, inverter and cylinder will all add to it. Summer will be hot, running cooling via UFH should offset the heat some what.

I did plenty of testing. On a light use day a big hysterisis may mean your whole cylinder drops well below a usable temp. A normal use day it may be fine, but suspect you will have difficulty conversations with the other half, when the shower is like warm at best. So be ready for your head on a plate

If you use thin battens they will split, but there are screws and screws. Using self drilling screws makes a big difference, 50mm battens makes things better also

That's pretty normal Maybe not the best tariff for winter, Cosy may be better. Fill up at 15p/kWh You may actually make a loss in real terms if you are paying to charge and then discharging with round trip losses. Not sure about that, its more about being on the correct tariff. My electric cost to buy is currently 15p, excess PV I get 15p. I never charge battery to get paid for discharging only, only export excess energy from PV.

Why do you need a floor sensor for that? A room sensor does that anyway. If a room sensor breaks its an easy job to replace, not so sure about a floor sensor.

For the information it gives, would not bother. Certainly no need for cooling as your plumbers says. Pump at 17 degs, humidity will never be an issue - ever. I did short bursts at 12, with zero issue. Heat pump off, circulation pump on, will tell you way more than the odd probe in the floor, you can see solar gain and chart floor temperature drops and rise rates for heat and cool. Generally if you need more than a manifold and possibly a single thermostat (if the heat pump controller doesn't do that function) you are over thinking it. The thermostat should do heat and cool with in build humidity sensing. Humidity sensing is belt and braces for cooling and serve as as safety cut out off, if you or someone has been messing with controller

I would keep it simple and not bother with the complexity, for the small gains if any you would have.

Area is small for use as a heat source, it's expensive, in summer house over heat would charge ground, but only if you had no insulation. Big risk of freeze if you strip too much heat. So no.

The 150m² multiple zones I covered with a thermostat in hall and another in ensuite controlling a towel radiator (direct electric). Use the thermostat to trip the ASHP off, if I have the fire on in winter and for summer cooling. The rest is cover by 5.20b and 5.22a. High thermal mass buffering via thick screed floor and a thermostat in a room served by the heating circuit, in my case the hall. But I have a temperature sensor in each room, most are not generally used except for monitoring temperature. They are useful to understand what is happening, how your system performs, system balancing etc.

I use Rye Oils, cedar oil, one single coat lasts a couple of years, now done two coats and 5 years in and is due a coat before summer.

If you have access to the settings, they change how slowly or quickly the heat pump responds to change. Useful for some matching of water volume and/or heating system and rate of change to things like return temperature. So for fan coils you can speed things up and thick screed floors slow the whole response down. It acts like a stiff damper in one direction and weak damper in another.

If they cannot quote for a new build with good plans zero hope for a normal house, with no plans. Just cut out the middle man, buy yourself, then claim the vat back. So far finding direct cylinder heating via immersion for domestic hot water isn't that expensive, so a direct immersion cylinder is about £500 compared to £1500 for a heat pump one. Then get as small a heat pump, as your heat loss allows. Direct couple ASHP to your heating system. Super simple install, just two pipes.

I did Durisol ICF, used ready mix and a pump lorry, me, my assistant, ready mix lorry driver and pump lorry driver, was the full team. Someone else near me did the full pour via a mixing hopper and Tele handler all on his own, mixed it, poured it. So you don't need a full team, makes life easier and faster. Durisol (now Ecobrix) are easy to fill you are only filling 5.5 rows deep at a time. No special equipment needed just OSB support patches are cut joints and corners, so very DIY friendly. Concrete pump (36m boom) was £560 for 8 hrs. I did my build during COVID restrictions, which included the Durisol training centres being closed, so I had the build manual to rely on. Just followed the steps laid out in the manual and zero issues. Note: I like to read manuals, many people don't, Ecobrix manual is very comprehensive.