How many thermostats/zones for a new build

muddle84

Hello all. Building a new house and going with air to water and underfloor heating upstairs and downstairs. The house is approximately 2500 square feet.
Just wondering how many zones should we split the house into, the standard quotes i have got have included one stat for downstairs and one for upstairs.
What are peoples experiences with this? should the kitchen and living area have its own zone?

freddyuk

I have 5 zones in a bungalow. Self installed. Pipe and programmers are cheap enough but retrofitting is very expensive. In a house it's much worse.
None of it makes any sense at all if occupants do not close the damn doors.!! I fitted a self closer on internal door to solve the problem.
I have mixed radiators and underfloor all closely controlled by programmable stats.
In a small house upstairs and downstairs is probably all you need however bathrooms need to be warmer than bedrooms so pipe it in now.

muddle84

freddyuk wrote: »

I have 5 zones in a bungalow. Self installed. Pipe and programmers are cheap enough but retrofitting is very expensive. In a house it's much worse.
None of it makes any sense at all if occupants do not close the damn doors.!! I fitted a self closer on internal door to solve the problem.
I have mixed radiators and underfloor all closely controlled by programmable stats.
In a small house upstairs and downstairs is probably all you need however bathrooms need to be warmer than bedrooms so pipe it in now.

Where are your actual zones? I presume water is one, then living room? Bedrooms? Kitchen?

freddyuk

Of course it depends on your layout. I have 2 beds and bathroom one end of house with doors so that is 1. Next is living room and kitchen open plan so that is 2.
Then middle room(winter snug) with cloakroom and office room off so that's 3. Then bedroom and bathroom off which is 4 and then conservatory (large) with UFH that's 5. Water is a separate valve so 6 if you count that. Wood burners in snug and conservatory using cheap forestry logs.

Also have 2 pumps as one for radiators and one for UFH via mixer valve. Can't have 2 pumps in S Plan system so you need a couple of relays to switch them separately. ......... you did ask:D

muddle84

freddyuk wrote: »

Of course it depends on your layout. I have 2 beds and bathroom one end of house with doors so that is 1. Next is living room and kitchen open plan so that is 2.
Then middle room(winter snug) with cloakroom and office room off so that's 3. Then bedroom and bathroom off which is 4 and then conservatory (large) with UFH that's 5. Water is a separate valve so 6 if you count that. Wood burners in snug and conservatory using cheap forestry logs.

Also have 2 pumps as one for radiators and one for UFH via mixer valve. Can't have 2 pumps in S Plan system so you need a couple of relays to switch them separately. ......... you did ask:D

Thanks for the freddyuk!! That's a great help! The more detail the better 😀

Count Mondego

Too many zones can be a bad thing, each or them calling the heat pump at different times means that it's starting and stopping more. What's the advantage to having a zone in every room when essentially the floors that you're heating is one big slab anyway?

Living area at 21 and bedrooms at 18 is all you need.

freddyuk

Count Mondego wrote: »

Too many zones can be a bad thing, each or them calling the heat pump at different times means that it's starting and stopping more. What's the advantage to having a zone in every room when essentially the floors that you're heating is one big slab anyway?

Living area at 21 and bedrooms at 18 is all you need.

No it isn't.......

Count Mondego

freddyuk wrote: »

No it isn't.......

Great point, well argued.

John.G

One would have thought that generally, HPs run most efficiently at very low temperatures and heating on 24/7, oil/gas boilers can get any zone up to temperature very rapidly, well within 2 hrs after overnight shutdown. How long, I wonder, does it take a UF heating (HP) zone under similar circumstances, to get up to temperature or is a different "zoning philosphy" used?.

freddyuk

Count Mondego wrote: »

Great point, well argued.

I explained my set up in detail. We do not want the same temperature in the bathroom and the bedrooms. Underfloor is piped in circuits with each circuit heating a different zone. You don't need to just have upstairs and downstairs zones and "live with it". Background temperature around 16/17c which is then boosted maybe 2 hours before required temperature. Bathroom has Towel radiator plumbed into the circuit so warms up quicker. With log burners you are boosting the UF in any room very quickly as the room is not cold. All very flexible and efficient. If the HP cannot handle being turned on/off a few times a day it may not be up to much.

Which reminds me if you live anywhere near the coast think carefully before going for this option.

John.G

Is your HP compressor variable speed drive??.

muddle84

Well the supplier answered my question for me. There is 4 zones upstairs and 6 downstairs in the design they made up for me! Pretty much every room has a seperate zone.