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underfloor heating ground floor only?


Fourbarewalls1

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Planning on installing underfloor heating to our barn. The ground floor measures 124m2 and will be totally opened plan, we will be installing a large wood burner 16-20kw, this will be sited in one corner of the barn so will not heat the full ground floor level.

I'm looking for the experience of those that have installed underfloor heating to see whether just installing it on one level the ground floor level will be enough to keep the barn warm.

At the moment I have received cost for underfloor heating system £5000 for both floors, water cylinder £800 and boiler £1000 this is without a gas or oil tank situated outside.

Look forward to hearing from you all

Lee
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We've got underfloor water fed heating in our house with concrete floors with tiles downstairs and wooden floors upstairs.  We got our system specd foc by wirsbo in uk (uponor now its called) and bought it through plumbase in the uk who kindly let us have some of the trade discount.  My DH installed it all himself, our house is about 80m2 and was fairly easy installation, cant remember how much the underfloor alone cost as we had it backed up with solar panels.  (Although the solars aren't efficient enough to run the hot water in our house and the heating in the winter so we have huge electric bills and are now installing an oil boiler)

We're contemplating a huge barn renovation project which will be about 140 downstairs and eventually 140 upstairs but we're going underfloor downstairs (wirsbo rough estimate under £3000) we'll get a water cylinder and gas boiler and tank here and we're more inclined for radiators upstairs, we do like the underfloor upstairs but as we have wood coverings it doesnt heat up as much as downstairs and I like radiators to dry clothes on. DH wants underfloor on both levels but im hoping to persuade him, we'll have a woodburner for ambiance and for the cooler spring/autumn evenings.

hth

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Just a note.

 

Underfloor heating is perfect for a evacuated tube solar system as it runs on lower temps than radiators.

 

If you want to know more about how to get your heat Free (end ecologically) then PM me and I keep you informed of the installation on my house.

 

Andrew

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  • 4 weeks later...

Recommend you use electric UFH, ground floor only - even on buildings with high ceilings the heat penetrates the fabric of the house very well. If you have bathrooms upstairs then maybe consider UFH for these.

Electric UFH is much more controllable than wet and in the event of faults wet systems are just not easily fixed. It is also worth mentioning that with wood the temp must never reach 27 degrees as the floor can be irreparably damaged - with eloectric UFH the thermocouples are actuall in the floor itself so the situation does not arise.

Good luck with the projects

Marc

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We have geothermal underfloor heating downstairs and via radiators on the 2nd floor as we also have wooden floors, if we could turn back time it wood have been better to have had concrete floors and underfloor heating upstairs also ( I would have liked a stone floor!!). You can nowadays have underfloor with a floating wooden floor with special parket ( kiln dried drier!) On the matter of Electric underfloor, our friends have this on a much much smaller scale, a relatively new installation and they had to turn if off half way through winter and resort to a parafin heater as the electric bills were so high.

Lilly

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Hi Lilly,

We have underfloor heating both down and upstairs. Our house is about 14 years old and the system has been in since it was built. During the winter we only have the heating on downstairs, apart from the bathroom upstairs as we find it gets too hot. We have a logburner as well, but that is really for ambience as we don't seem to need often.

Regarding a solar sytem with evacuated tubes, I agree with Poolguy. You could run your hot water and heating system from it during the winter, topping up if required from your boiler. During the summer months, you should be able to divert the extra hot water to heat a pool. Electric underfloor heating is expensive and will only get dearer, even if you have superb insulation. You are far better off going for solar heating using evacuated tubes. The payback time is a few years and obviously almost free after that. Also, you will receive money back on your tax return. I'm installing my own solar panel at the moment (when I can find the time!). At the time I purchased the system, it was too expensive to have another coil put into the water tank to link up with the underfloor heating. However, if we decide to stay here, I will look at installing an additional tank and system to do just that.

Regards

Paul 

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[quote user="Paul Bradford"]

Regarding a solar sytem with evacuated tubes, I agree with Poolguy. You could run your hot water and heating system from it during the winter, topping up if required from your boiler. During the summer months, you should be able to divert the extra hot water to heat a pool. Electric underfloor heating is expensive and will only get dearer, even if you have superb insulation. You are far better off going for solar heating using evacuated tubes. The payback time is a few years and obviously almost free after that. Also, you will receive money back on your tax return. I'm installing my own solar panel at the moment (when I can find the time!). At the time I purchased the system, it was too expensive to have another coil put into the water tank to link up with the underfloor heating. However, if we decide to stay here, I will look at installing an additional tank and system to do just that.

Regards

Paul 

[/quote]

As regards cost of running electric UFH I can only surmise that the system Lily eluded to (friends installation) was badly designed - this is easily done and the watts per linear metre is the primary calculation. There are also a number of systems where the efficiency losses are high because of the quality of cable / components used.

We have also coupled an electric energy saver (power factor correction unit) with one system and this has provided even better results with the electric UFH.

Both wet and electric systems can be laid under all types of floor finishes but as Lily mentions concrete provides a better thermal mass and tends to respond quicker. It the 'TOG' rating (just like quilts) of the materials that matters.

Geothermal is generally considered best due to the Co-efficient of performance (CoP) which is generally 4:1 or greater. That said, you also have to remember the cost of installing a GSHP whihc is substantial and motors / compressors do wear - we do know of some whose system components have failed prematurely (to be fair one was because of bad maintenance by the customer) with cost of repair being prohibitive - you can of course usually only get the spares from the particular supplier / manufacturer with the associated high costs of such.

The CoP of aerothermal is getting better so this technology is becoming a favourable option for heating.

I have to say categorically that Electric underfloor heating is neither expensive to purchase or costly to run. It depends on whose system is chosen and how well it was designed.

Unfortunately I have to disagree about the viability of solar for central heating - domestic hot water yes great, heating, NO.  Unless you have a substantial Thermal store it just cant cut it - here is what a colleague of one of the above gents says regarding solar for heating.

There is 10 times more sun energy in the summer than in the winter. (this is the reason for the different seasons, after all). Therefore you immediately have the problem that the bulk of the energy is at the wrong time of year. The other problem with using solar to heat your house is that it is not present at the times when it is really cold - at night, on very overcast days, in winter evenings etc.
In practice you can provide a significant amount of supplementary heat in the spring and autumn (and some people have implemented such systems), but the contribution in the winter will be minimal, restricted to sunny days, but you will need to fit many more panels, as heating a house is a lot larger task than heating an insulated cylinder of water. Solar water heating on the other hand, can be effective even in the winter, as the amount of heat required is considerably less than that required to heat a house.

I do have some reports on this subject if you wish to study it further. 

Well, guess thats really confused things now so extract what you can

Regards

Marc

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Hi Ecopower,

My friends installation was carried out by a very reputble electrician heating engineer and knowing these friends no cost cutting would have been applied to the materials, now allowing for the fact that mistakes can ad do happen may be this was the case but than that would have to be true to all installations no matter by whom they are laid.

When we did the research (very extensive it was too!) and not entirely by me, I flick the switches and make tea !!! ( proberbly not doing myself justice really but you get my point) Comparing Devis for good quality oil / gas systems and if you factor in the reimborsement of 50% on the specific material and labour costs of geothermal linear method it was very much in favour of going Geo as it came out the same for gas, or oil but with this option being cheaper to run after! On top of this we did all the donkey work , dug out the area for the capture and re filling after, posing of all the radiators and we laid the underfloor pipework and insolation with a scematic of course and the patron came and checked that we had indeed installed properly no kinks etc and quite a few other things, we had them do the important stuff involving electricity and anything we felt that a true professional should thus also preserving our guarentee. Incidently would your friends problems have been covered by the extensive Guarentee for premature wear and tear and I fail to see what they have neglected to do that is specific to a geothermal installation and would the same neglect have caused problems for any other system including Electric.

I would be intersted to know how effective these evacuated tube panels work as don't they work on UV so it is not so necessary  for it to be sunny. My opinion so far is in an ideal world and to an extent money as side if you can fork it out up front, a dual solar plus geo is worth considering. We have a River with good continuas flow and I would like to harness this really but I'm not sure how the Architec de Batiment de France or whom ever would feel about that!!.

Not really changing the subject by the font has changed and I don't mean to shout or stand out, but I'm not quite sure how to change it back?

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[quote user="Lilly"]

Hi Ecopower,

My friends installation was carried out by a very reputble electrician heating engineer and knowing these friends no cost cutting would have been applied to the materials, now allowing for the fact that mistakes can ad do happen may be this was the case but than that would have to be true to all installations no matter by whom they are laid.

When we did the research (very extensive it was too!) and not entirely by me, I flick the switches and make tea !!! ( proberbly not doing myself justice really but you get my point) Comparing Devis for good quality oil / gas systems and if you factor in the reimborsement of 50% on the specific material and labour costs of geothermal linear method it was very much in favour of going Geo as it came out the same for gas, or oil but with this option being cheaper to run after! On top of this we did all the donkey work , dug out the area for the capture and re filling after, posing of all the radiators and we laid the underfloor pipework and insolation with a scematic of course and the patron came and checked that we had indeed installed properly no kinks etc and quite a few other things, we had them do the important stuff involving electricity and anything we felt that a true professional should thus also preserving our guarentee. Incidently would your friends problems have been covered by the extensive Guarentee for premature wear and tear and I fail to see what they have neglected to do that is specific to a geothermal installation and would the same neglect have caused problems for any other system including Electric.

I would be intersted to know how effective these evacuated tube panels work as don't they work on UV so it is not so necessary  for it to be sunny. My opinion so far is in an ideal world and to an extent money as side if you can fork it out up front, a dual solar plus geo is worth considering. We have a River with good continuas flow and I would like to harness this really but I'm not sure how the Architec de Batiment de France or whom ever would feel about that!!.

Not really changing the subject by the font has changed and I don't mean to shout or stand out, but I'm not quite sure how to change it back?

[/quote]

Hello Lily,

As regards electric UFH it is impossible to comment on a specific installation other than to say that from case studies our system comes out very well.

For Geothermal with wet UFH you have done exceptionally well to undertake a lot of the work yourselves with a huge reduction in costs by doing so. You are right that for a good quality boiler the cost can also be high but the savings you have made with your own labour are huge. Fot that I can only congratulate you.

I'm not sure I understand the point you elude to as regard our friends installation?

Solar evacuated tube systems work exceptionally well for domestic hot water and for pools. You will find lots of information about these systems but I speak from experience. They work and you are right, they work on UV and as the tubes are evacuated ambient temperature has virtually no effect upon perfromance.

If you have a dependable water source whihc runs through your  property then do try and use it. Absolutely the best form of renewable energy period.

Kind regards

Marc

 

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Thank you for your responce ecopower, it was indeed a great saving but bloody ard work and no one should take it on lightly.

With regards my statement re my friends installation was only in response to your statement and I just wanted to reassure you that it was carried out with all the best intentions thats all.

Marc if you know more about capture from a water source and or regs please feel free to PM.

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Hello Lily,

I'll send you a PM (if I can find out how to?) - we have a lot of enquiries about both water turbines and water wheels (excellent machines) and Hydro power is always the best investment if you have a dependable water source.

Regards

Marc

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  • 1 year later...
We bought a newly built house in August which has electric underfloor heating downstairs and convector heaters upstairs. It's got concrete floors throughout, and presumabely the latest spec insulation together with double glazing,

We only got hold of the instructions for the CH last week. It has various factory set programmes; on all day, on morning and evening and on three times a day.

We switched it on but other than the meter flying round there was no change in temperature and the tiled floors felt no warmer.

Is this normal? Is it not working? If it's this slow to react what's the point of having various on/off settings during the day? Would it work most economically overnight on off peak rlectricity?

Any advice gratefully received
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When you say that it was slow to react how long did you leave it on for?

I have storage heaters and by the time I switch it on for the winter the cold snap has already begun, I dont have a floor slab to heat other than indirectly but nonetheless I find that it takes a few days for the heat to soak through the fabric of the building before things start to feel warm.

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I wonder if it's zoned so as not to trip out the board on surge so maybe it's set up and  the meter is flying round while the upper areas get to temp then as upstairs gets to temp the  underfloor cuts in?

Personally I would try and have it set up the other way about and have warmth rising through the building possible that the controls are wired ga ga or that you haven't got the stat for the underfloor set ie it's not calling for heat.

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I think you may have a controls problem electric underfloor is generally laid on insulation and directly under the tiles it heats up very quickly and seems to be de-rigeur in a lot of French new builds down our way. I would say those that I have seen you can feel it within ten minutes and its fully warm in 20.

I wonder if they have forgotten the insulation or put the matrix below a screed either way its not hours, are you sure that its not electric up stairs and wet downstairs?

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[quote user="Pommier"]We set it for downstairs (Underfloor) only with the upstairs (radiators) switched off. We had it switched on for 5 or 6 hours - maybe that wasn't long enough? It seems as if it might be a rather expensive form of heating![/quote]

We ha-e an electric heating mat installed directly under the tiles with insulation under the mat and  the tiles are warm within an hour. We switched it on at 2.00 pm today and had to switch off at 6.00 pm we were so hot. Do you know whether there is a heating mat under the tiles or if a cable system has been laid in the concrete subfloor? If the cable is in the concrete it will act like what we know as night storage heaters and take a while to heat up and similarly a long time to cool down.

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Unfortunately I don't know what sort of underfloor heating we've got. We bought the house ready built (I think it had been completed 12 months ago) and have never seen the builders - even at the signing they'd appointed a proxy.

We've been waiting for them to do the snagging since September which includes ensuring that the heating works as it ought, but it'd be good if we could know what we can reasonably expect from it. I would suspect that since one of the programmer options gives a lunchtime boost, it ought to be fairly quickly reactive.
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[quote user="Pommier"]... and have never seen the builders - even at the signing they'd appointed a proxy.

We've been waiting for them to do the snagging since September which includes ensuring that the heating works as it ought, [/quote]

If you know the name of the company who built the house then can you not get in contact with them and ask when they are going to do the 'snagging'? Either that or approach the estate agent you bought the house through and explain your situation. They should help you out especially if they hope to sell on the house for you one day.

Sue

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[quote user="Pommier"]The notaire is also trying to get them moving, but if nothing happens soon I'll see if the legal insurance included with the house insurance would pay for an advocat.[/quote]

Perhaps there might be no need for that at this point - sometimes just the threat of using your 'assurance juridique' prods a company into action.

Good Luck.

Sue

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  • 1 month later...
We are thinking of underfloor heating in an extension we are building, the rest of the system is 'wet' with normal rads, but the extension will have a higher ceiling and velux windows and be quite open etc and the size of rad we need might be a little large and difficult to place - are there any sites with calculations so we can see if it would work for us ? (we're in the UK)
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