Grooved concrete vs overlay floor board underfloor heating ?

everfor007

I am planning to install the underfloor heating to my bunglaow which has concrete floor. Got two quotes from different company
1.One company called jk underflooring heating, they are directly making a groove to concrete layer and inserting the pipe and top on that  adivsing us to install the flooring tiles directly with out any matting/insulation.

2. Another company, using on above concrete layer of installing EPS overlay floor planel board, pipes and top fermacell flooring element and after installation, total height increase over 50mm..

I got feeling first option will have loss heating, as heating pipe  directly exposed to concrete.

 And second option is very expensive, double of the first one.

I am not too techincal, can you advise which underfloors option is more effective and worth for money?

FFHillbilly

I don't understand option 2 are there some typos in it?
is there insulation below your existing floor?

everfor007

First option of installation image 


Second option of installation image

gm0

Hard to be prescriptive.  Retrofit compromises.

UFH pipes sat over insulation beneath flooring can act as a large and low temperature radiator (option 2).  Workable heat distribution but somewhat limited storage.  It should do what it sets out to do consistently.

But a new build would probably lay an insulated slab so that heat could be built up and stored in a high heat capacity large mass. e.g. from solar electric dumped via heatpump into the slab when solar available to heat it up before autumn.  So more like option 1 - but the slab has to be the right structure for the purpose and ideally insulated from cold ground.  Which won't be true for an old school concrete floor which may not be insulated or thick enough. 

So option 1 is a compromise - without the disruption of digging it out to do it right or the height compromise of option 2.

Option 1 will be slower to respond for room heating than Option 2 and its "storage" performance could be quite variable with your exact sub floor conditions.  But it doesn't cut room heights.  Installer won't be interested in warranty on how well it works with old sub-floors they had nothing to do with.

For retrofit few of us want to dig out our concrete floors, support walls, lay insulated slabs and build back up.

Option 2 is more likely to perform to a known specification - fewer variables but with the cost and room height compromise

FFHillbilly

so is there insulation below your existing floor?

EssexExile

Can you tolerate a 50mm loss of headroom? I'd be bashing my head every time I went through a doorway. If you don't mind that, what about visitors and potential buyers later?