Should I get underfloor heating?

Bendy_House

Exodi said:

I have wet UFH throughout downstairs and radiators upstairs so to give my perspective on things -

1) Time - it takes significantly longer to 'feel' the heat from UFH compared to radiators - as the heat has to heat and travel through a solid materials, compared to just travelling through the air like a radiator. This means if I'm cold, I can switch on a radiator and feel the warmth from it in a couple of minutes, UFH on the otherhand may take a couple of hours. On the flipside, after switching off the radiators, the heat will soon start decreasing, whereas UFH may stay hot for hours after they are switched off. For this reason, UFH is best combined with thermostats and routines - they are not great if you're reactive (e.g. 'it's cold this evening, I'll put the heating on' - all this will do is keep the house warm during the night).

2) Spread - while the hottest point of a room with a radiator in is obviously around the radiator, with UFH the heat is even spread across the floor making the whole room an even temperature.

While I do think UFH is superior, I wouldn't consider retroactively installing UFH.

I think that pretty much sums it up! As someone else remarked, in a room with, say, high solar gain, UFH might be even less sensible as it's so slow to react.

Since UFH isn't required for low-temp wet systems - ie oversized rads should do the same efficient job - then I'd only suggest installing it if you prefer the comfort it gives. I've only had two, well three, experiences of UHF; one was in a village hall where my kids went to a party, and I immediately sensed on walking in that the heating effect was different - I was really impressed, especially so when I sat down on the floor. Another was a during a stay in a holiday cottage, again a very comfortable experience. And I've just been reminded how lovely UFH is as mil has just moved in to a bungalow which has the whole place zoned out in wet UFH. She fitted LVT throughout, and it's a joy to walk on barefoot!

It is very comfortable in there - always cosy, but not oppressive. Actually, the heating has barely been on since she moved in, as the weather has been so mild and with plenty of sunshine. It'll be interesting to see what it's like in winter, but I suspect even more 'comfy'.

So, I'd only go UFH for the comfort, if you prefer that form of heating.

anon_ymous

Bendy_House said:

Exodi said:

I have wet UFH throughout downstairs and radiators upstairs so to give my perspective on things -

1) Time - it takes significantly longer to 'feel' the heat from UFH compared to radiators - as the heat has to heat and travel through a solid materials, compared to just travelling through the air like a radiator. This means if I'm cold, I can switch on a radiator and feel the warmth from it in a couple of minutes, UFH on the otherhand may take a couple of hours. On the flipside, after switching off the radiators, the heat will soon start decreasing, whereas UFH may stay hot for hours after they are switched off. For this reason, UFH is best combined with thermostats and routines - they are not great if you're reactive (e.g. 'it's cold this evening, I'll put the heating on' - all this will do is keep the house warm during the night).

2) Spread - while the hottest point of a room with a radiator in is obviously around the radiator, with UFH the heat is even spread across the floor making the whole room an even temperature.

While I do think UFH is superior, I wouldn't consider retroactively installing UFH.

I think that pretty much sums it up! As someone else remarked, in a room with, say, high solar gain, UFH might be even less sensible as it's so slow to react.

Since UFH isn't required for low-temp wet systems - ie oversized rads should do the same efficient job - then I'd only suggest installing it if you prefer the comfort it gives. I've only had two, well three, experiences of UHF; one was in a village hall where my kids went to a party, and I immediately sensed on walking in that the heating effect was different - I was really impressed, especially so when I sat down on the floor. Another was a during a stay in a holiday cottage, again a very comfortable experience. And I've just been reminded how lovely UFH is as mil has just moved in to a bungalow which has the whole place zoned out in wet UFH. She fitted LVT throughout, and it's a joy to walk on barefoot!

It is very comfortable in there - always cosy, but not oppressive. Actually, the heating has barely been on since she moved in, as the weather has been so mild and with plenty of sunshine. It'll be interesting to see what it's like in winter, but I suspect even more 'comfy'.

So, I'd only go UFH for the comfort, if you prefer that form of heating.

Thanks. I'll go for oversized radiators instead then (Assuming my current ones wouldn't already be considered to be oversized, if I'm adding more insulation) 

Bendy_House

waqasahmed said:

Thanks. I'll go for oversized radiators instead then (Assuming my current ones wouldn't already be considered to be oversized, if I'm adding more insulation) 

Good point! If you significantly upgrade your insulation levels and cut down on drafts, then the way you heat your home should change to a cooler boiler output temp, and not allowing it to 'cycle' at its previous high rate, relying on TRVs and room 'stats to turn it on and off.

It is a balance betwixt energy savings and initial outlay. Any rad you swap is going to be - what? - ~£200? That pays for a fair bit of gas, so generally not worth doing for a few % of energy savings. But, if a rad needs replacing anyway, then, youknow...

anon_ymous

Bendy_House said:

waqasahmed said:

Thanks. I'll go for oversized radiators instead then (Assuming my current ones wouldn't already be considered to be oversized, if I'm adding more insulation) 

Good point! If you significantly upgrade your insulation levels and cut down on drafts, then the way you heat your home should change to a cooler boiler output temp, and not allowing it to 'cycle' at its previous high rate, relying on TRVs and room 'stats to turn it on and off.

It is a balance betwixt energy savings and initial outlay. Any rad you swap is going to be - what? - ~£200? That pays for a fair bit of gas, so generally not worth doing for a few % of energy savings. But, if a rad needs replacing anyway, then, youknow...

I am probably gonna get either Tado or Netatmo too. The house I'm buying has a brand new (ish) boiler that's already 93% efficient, so that's something . It isn't a good brand but hey it's got a five year warranty. 

It's this one 
https://www.boilerguide.co.uk/productinfo/vokera/easi-heat-plus-29ci-combi-gas-boiler

Then, when it comes to 2035, you won't be able to even buy a new boiler anyway. I'll look into draught proofing too, because that's quite cheap, relatively speaking, and I'll play around with the temperature on the boiler, to hopefully get the same heat with lower flow rates. 

If I can get it to 45C and still have heat, then I don't even need oversized rads

Chickereeeee

I have learnt a bit about UFH here. I am planning to extend my house with a 2 story extension, which will increase the ground floor area by about a third (converting L shaped house to square.) The new bit will be insulated to latest high standards. The old bit is draught proofed very well, but no extra insulation on/in cavity walls. New extension will 'remove' two of these outside walls, of course. Now I am not sure what to specify for heating the extension UFH (in screed) UFH (surface mount) or radiators (as rest if house is currently).

Bendy_House

waqasahmed said:

Bendy_House said:

waqasahmed said:

Thanks. I'll go for oversized radiators instead then (Assuming my current ones wouldn't already be considered to be oversized, if I'm adding more insulation) 

Good point! If you significantly upgrade your insulation levels and cut down on drafts, then the way you heat your home should change to a cooler boiler output temp, and not allowing it to 'cycle' at its previous high rate, relying on TRVs and room 'stats to turn it on and off.

It is a balance betwixt energy savings and initial outlay. Any rad you swap is going to be - what? - ~£200? That pays for a fair bit of gas, so generally not worth doing for a few % of energy savings. But, if a rad needs replacing anyway, then, youknow...

I am probably gonna get either Tado or Netatmo too. The house I'm buying has a brand new (ish) boiler that's already 93% efficient, so that's something . It isn't a good brand but hey it's got a five year warranty. 

It's this one 
https://www.boilerguide.co.uk/productinfo/vokera/easi-heat-plus-29ci-combi-gas-boiler

Then, when it comes to 2035, you won't be able to even buy a new boiler anyway. I'll look into draught proofing too, because that's quite cheap, relatively speaking, and I'll play around with the temperature on the boiler, to hopefully get the same heat with lower flow rates. 

If I can get it to 45C and still have heat, then I don't even need oversized rads

Blimey, that boiler is cheap! I thought Vokera were ok? And a 5-year warranty is good.

45oC will heat your house? Not a chance... :-)

anon_ymous

Bendy_House said:

waqasahmed said:

Bendy_House said:

waqasahmed said:

Thanks. I'll go for oversized radiators instead then (Assuming my current ones wouldn't already be considered to be oversized, if I'm adding more insulation) 

Good point! If you significantly upgrade your insulation levels and cut down on drafts, then the way you heat your home should change to a cooler boiler output temp, and not allowing it to 'cycle' at its previous high rate, relying on TRVs and room 'stats to turn it on and off.

It is a balance betwixt energy savings and initial outlay. Any rad you swap is going to be - what? - ~£200? That pays for a fair bit of gas, so generally not worth doing for a few % of energy savings. But, if a rad needs replacing anyway, then, youknow...

I am probably gonna get either Tado or Netatmo too. The house I'm buying has a brand new (ish) boiler that's already 93% efficient, so that's something . It isn't a good brand but hey it's got a five year warranty. 

It's this one 
https://www.boilerguide.co.uk/productinfo/vokera/easi-heat-plus-29ci-combi-gas-boiler

Then, when it comes to 2035, you won't be able to even buy a new boiler anyway. I'll look into draught proofing too, because that's quite cheap, relatively speaking, and I'll play around with the temperature on the boiler, to hopefully get the same heat with lower flow rates. 

If I can get it to 45C and still have heat, then I don't even need oversized rads

Blimey, that boiler is cheap! I thought Vokera were ok? And a 5-year warranty is good.

45oC will heat your house? Not a chance... :-)

I though they were known for being cheap but not necessarily being good?

And aha. I mean, it's still worth playing with the dials and the lower the flow temp, the more efficient it is (Assuming that it can still heat the house up) 

ArbitraryRandom

DRP said:

waqasahmed said:

FreeBear said:

waqasahmed said: I'm waiting for ASHP to either match the price of boilers, or have a higher COP than 4.

From what I've seen of ASHP, a COP of between 2 & 2.5 is about the best you can hope for in the depths of winter. You might get up to 4 with GSHP, but the installation costs is much higher.

If I had the cash and suitable access to my rear garden for a big rig, I'd be drilling boreholes and installing a GSHP. As it is, I can only get something like a Dando Terrier in which limits me to a borehole depth of around 40m.

From what I've seen, apparently the biggy is the installer, and their knowledge, and how they design the system. Apparently heat geek installers average around 3.5 to 4 which at least puts us on parity with gas usage.

Still, either way, I imagine more people would put them in, if they become more efficient. We should hopefully be out of pre crisis as of maybe four years, but in that time period, gas won't meet parity with electricity bills especially given that 25-50% of our electricity is produced using gas. I then can't also see people installing these even with an average of COP of 2+ , at least in the medium term 

By 2025, I think we're meant to use more nuclear however 

Is there any nuclear due to come  online by 2025? Hinckley point C is currently 2027. 

The aim for the RR reactors was 2025. Don't know if that's changed since. 

https://www.edie.net/uk-government-kick-starts-approval-process-for-rolls-royces-small-nuclear-reactors/

markin

Hinckley point C was delayed 2 years from covid, but as far as i remember its only a replacement for the ones planned to close.

Im sure you could have the UFH always on at 16c and use a rad for Fast heat in the evening as needed.

Also Air to Air heat pumps are great for the shoulder months and fast reaction.