Underfloor heating, cost effective or not!

[neilymack]

Hi all
I am thinking of installing underfloor heating throughout the downstairs area of my house and also my bathrooms upstairs. In total it will be approximately 43m2 downstairs over 5 rooms and the 2 bathrooms upstairs that covers around 9m2. Obviously the other option is radiators. I am currently renovating the whole house so I will need to purchase something if the underfloor heating is a non starter. I will need 9 of those in total for the areas mentioned.
I have read all the manufacturers stuff on the underfloor heating and lets face it they are all biased. I am looking for users perspective of it and also an idea of its benefits and pitalls and also if it is cost effective.
Water fed systems or electrical??
Any advice greatly appreciated.

 

[tamz]

cost effective.

As a retrofit.....NO.
Would involve an overlay (basically a new floor on top of existing) which would mean skirting off, doors altered, bathrooms out and refitted, bottom tread on stairs a different height etc or lifting (or digging up) the full ground floor and relaying. It is a lot of work and expense.

Electric is too expensive to run.

Just put in a std system with radiators.

 

[Agile]

The other problem is that the heat output would probably be insufficient for the rooms.

It also has a very long time constant which gives control problems unless you are retired or work from home.

Tony

 

[tamz]

control problems

Tony have you noticed that all these smart rsed things that are supposed to save energy , in reality don't?

Eg i've got a "smart" wc system on mine and in the past week i've been at home earlier, doing the garden plants stuff and noticed the boiler kicking in between half 3 and 4.
Now the heating is set to come on at half 5, the weather has been quite mild, around 60 deg (although it was snowing wed morning but nice day). The "smart electronics have decided to come on up to 2 hrs early to get the house to temp because i have the windows open!
Now i know that the house is up to temp in half an hour so wee job for through the week is put in a timer and a stat

 

[neilymack]

Thanks guys.
Its amazing how different peoples perspectives are of the same product. I still have a friend banging on about how great it is but I must say, I completely agree with you Tony. I hadnt thought about it but I do think the time constant is a major issue for me. I am not even at home for half the year and my wife is out most of the day and my daughter is in nursery. Pointless.
I just thought clearing the rooms of radiators would give us more space. Oh well. need to find some good, nice radiators now as the wife hates the standard ones!
Thanks again and any other ideas for the heating sources or designs would be appreciated!

 

[RigidRaider]

It's nice in bathrooms where you go barefoot though!

 

[ianniann]

It also has a very long time constant which gives control problems unless you are retired or work from home.

You just can't win, can you? Designers put massive effort into complex controllers to try and maintain a constant temperature inside the house from a mechanism (ie. metal tanks full of hot water) that isn't really good at doing that and to operate it in a way that is compatible with condensing boilers. Then someone comes up with a system that is tailor made for maintaining a constant temperature inside the house and for being efficient with a condensing boiler (ie underfloor heating) and it gets criticised for being difficult to control

Don't go electric unless you're really wedded to the idea of UFH and can't do it any other way. Do the sizing calculations to make sure it is viable. Poorly insulated houses may be a problem and you might need an additional heat source for really cold days. Or more insulation! You might want an additional heat source anyway in a living room just as a focal point. Or not, depending on your taste. Another rule of thumb is big rooms work well with UFH, small rooms not so well. You won't save massive amounts of energy by having underfloor heating, but you should save some. You have to work out whether it is worth the extra cost and effort up front.

If your friend has it already, ask about things like how long it takes to heat up in the morning, which controllers they have fitted, etc. No substitute for first hand knowledge.

 

[htgeng]

control problems

Tony have you noticed that all these smart rsed things that are supposed to save energy , in reality don't?

Eg i've got a "smart" wc system on mine and in the past week i've been at home earlier, doing the garden plants stuff and noticed the boiler kicking in between half 3 and 4.

You can't blame the controls as they are just doing what they are designed to do. Check the setup options for a 'summer switch off' feature. That allows you to specify an outside temp above which the boiler will not fire up on central heating. Otherwise, just do what I do and turn the controller off. Given we had a harsh winter, when its more than 10c outside, we can cope without the heating on.

 

[greemyamochop]

retro fitted in my own property and its the best thing ive spent money on