Is underfloor heating more costly to run?

[u587162]

Generally speaking, does underfloor heating cost more to run than having radiators?

We're having an extension built (dimension A is 41m2 and another dimension B is 21m2). I am aware that it is not easy to make a direct comparison because they are two different systems and underfloor heating is perhaps more efficient because of radiant heat etc, but given that the length of pipe in each area will contain more water than say radiators (but then I'm not really factoring in copper pipe runs etc), is underfloor heating more expensive?

Or could costs actually fall because of the efficiency attained?

Finally, is underfloor heating less prone to leaks / burst pipes etc as a result of not setting your heating to come on during winter time if going away on holiday etc (leaving aside the pipes supplying taps and toilets)?

 

[Richardthe3rd]

Generally speaking, does underfloor heating cost more to run than having radiators?

We're having an extension built (dimension A is 41m2 and another dimension B is 21m2). I am aware that it is not easy to make a direct comparison because they are two different systems and underfloor heating is perhaps more efficient because of radiant heat etc, but given that the length of pipe in each area will contain more water than say radiators (but then I'm not really factoring in copper pipe runs etc), is underfloor heating more expensive?

Or could costs actually fall because of the efficiency attained?

Finally, is underfloor heating less prone to leaks / burst pipes etc as a result of not setting your heating to come on during winter time if going away on holiday etc (leaving aside the pipes supplying taps and toilets)?

There's several reasons why UFH should be the first & only choice when it comes to heating;
1. It generally runs at a much lower temperature than radiators, so the lower temperature the boiler is on less & you save a shed load of money.
2. UFH is mostly a radiant heat, it heat you & the fabric of the building. Radiators give off converted heat, the hottest part of the room is the ceiling!!
3. All pipes are hidden, no radiator to try & paint behind or take up wall space.
4. The installation costs have come down greatly in the last 30 years, with many, many companies now specialising in the supply of the gear.

So it's really a no brainier in my view.
HTH

 

[u587162]

Good morning and thanks for your feedback!

Could you pls comment a little about 1. possible leaks v copper pipes, 2. retro fitting meeting up with new extension which will be done with secreed etc (costs, pitfalls etc)?

Thanks.

 

[gas112]

your first point richard the water maybe at a lower temp but if you have to heat far more of it for a far longer time then this is not cheaper.


Response time of under floor is far slower than rads which is one of it main downfalls

 

[Richardthe3rd]

Good morning and thanks for your feedback!

Could you pls comment a little about 1. possible leaks v copper pipes, 2. retro fitting meeting up with new extension which will be done with secreed etc (costs, pitfalls etc)?

Thanks.

The UFH system is installed & tested prior to the floor screeds/finish. So little or no chance of any problems with that type of system.

You can add UFH to any system.

The thermal mass is the important thing; pipes in concrete is best, the thicker the better. The more thermal mass the lower the running temperature.

 

[Richardthe3rd]

your first point richard the water maybe at a lower temp but if you have to heat far more of it for a far longer time then this is not cheaper.


Response time of under floor is far slower than rads which is one of it main downfalls

It runs 27/7 with an overnight set-back temperature & just ticks over during the day, so the time the boiler is on is limited. Even less with weather compensation systems. Also, the mean water temperature of UFH suits condensing boiler to a T, the lower temperature of say 40degC or even less, is ideal to have your boiler condensing longer.

There's every reason for UFH.

 

[gas112]

Jesus i knew there was more daylight hours in scotland in the summer but 27 hours that a fair length of day .
Still doesnt matter how limited the time of boiler i on if it on dozens and dozens of limited times a day were is your proof in facts and figures that its cheaper for the same level of room temps and comfort than rads

 

[Richardthe3rd]

Jesus i knew there was more daylight hours in scotland in the summer but 27 hours that a fair length of day .
Still doesnt matter how limited the time of boiler i on if it on dozens and dozens of limited times a day were is your proof in facts and figures that its cheaper for the same level of room temps and comfort than rads

LOL!! Oh yes, the Scottish Nazi Party(SNP) can walk on water mate. It's these cnts that have added 3 hours to each day........

Well, I'd say common sense would tell you with the thermal mass & the low mean water temperatures, the boiler is hardly on during the normal 27hour day.......

I don't have any figures mate to back up this though.

 

[Agile]

Richard, ( who we lovingly call Dick ! ) is not so correct about UFH but does have the right idea about the SNP.

Simply, to heat your house you need a certain amount of heat.

How you deliver that heat is up to you and it can be UFH, radiators or warm air!

But, apart from slight differences in radiant heat and convected heat the amount of heat is the same and calculated as the heat loss of the building. That's the amount of energy to keep the inside at say 21 C when its -1 C outside and is about 11 kW for a typical three bed semi.

Warm air takes about THREE minutes to warm up as air has a very low specific heat.

Radiators take about TWENTY minutes to heat up as they contain about 80 litres of water and have a heavy metal casings.

UFH contains about 60 litres of water but is normally surrounded by masses of concrete which can take up to TWO hours to heat up even though its to a surface of only about 30 C.

So as a result of the very slow warm up of UFH its running costs are always higher than other forms of heating because it has to be left on most of the time although a setback temperature a few degrees lower overnight can be timed into the system.

Its cheaper in England because we only have 24 hours in the day but more expensive in Scotland where the SNP have apparently imposed a local 27 hour day. If they still had any shipyards then I am sure the workers would not be very happy with that.

We did maintain some Trident subs in Scotland but the SNP wants them and their 2000 jobs gone.

Probably irrelevant now as the Ruskies have probably walked in and floated them away after one of the sailors leaked that they were never locked anyway!

Tony

 

[Richardthe3rd]

Tony, a property will not require the same amount of heat to counteract the building heat loss. Convected heat has more air movement, more air changes & a higher heat loss. Convected heat will also have a higher heat loss through any ceiling or roof - due to the fact that the ceiling has a higher temperature. Lastly, with convected heat the human body needs more than with radiant heat; the human body loses more heat by radiant heat & if you counteract that heat from the body with radiant heat, it's feels more comfortable.
With radiant heat; 17degC ambient feels like 22degC.

Once a building with a slab full of UFH is heated up, it takes very little heat to maintain that comfortable environment. Most people that have UFH would never go back to radiators or hot air heating - hot air heating of any kind is the work of the devil!!!

"Ye canna change the Laws of physics captain, but you can reduce the building fabric heat loss".........

 

[u587162]

Is it a good idea to put wet UFH in the bedrooms?

Is it better to perhaps have wet UHF in the bedroom and perhaps a radiator too? I'm always feeling cold and would be really upset if after spending all this money on UFH I still feel cold (I understand the bit about it taking longer to warm up its just even after its been on for a while, I dont want to feel cold and regret it).

How does one compare the systems sold by these big companies at exhibitions etc versus ones that builders put in themselves?

 

[Norcon]

Radiators are for the dinosaurs. And radiators under windows? Yuk...
People doing stylish new builds who have taste will only fit UFH.
Cold blooded women will always insist on rads of course.

Brother has it in his new build with GSHP compensated controlled.
Off peak night rate running then off most of the day with a slight boost in the evening.
It's a no brainer. Interior design and decoration then has free rein.

 

[vulcancontinental]

It's only a no brainer when it's suited to the building and the building rate of heat loss, ceiling height lots of other factors.

7 1000mm rads 600mm high, two of which are doubles; 30m of 22 and 60 of 15mm plus the boiler is around 50 litres Tony so I don't know how you worked out those figures.

Horses for courses.

UF is a lot more expensive to put in but in the right situation I am quite prepared to believe it is superior, it just isn't always the right situation.

 

[hertsboilers]

Hi David, I like to hear your view on the efficiency difference of the boiler between a radiator system and a UFH system, providing all other aspects are the same.

 

[u587162]

Here is the layout of my house after we finish it.

The ceilings in the ground floor are 2.8m high, less on the other floors. Only the kitchen, utility area and living room area will have solid concrete floors.

Any suggestions on anything to do with UHF based on this?