Insulation effectiveness

[flashuk]

Hi

First post here, and delighted to discover the forum before I embark on the UFH adventure! I'm converting my garage into a wine cellar and therefore insulating it. I am installing UFH onto a concrete floor (at ground level).

I plan to lay 10mm Marmox board then UFH mat + SLC, then tiles.

My question is how much impact does the 10mm insulation board have? Some people are telling me it is nowhere near enough, and that 50% of the UFH output will go down to heat the earth underneath. Is this the case and therefore I should be thinking about 20 or 30mm?

One other quick question while I'm at it. Do I need any kind of membrane installed? Have been reading and looks like a polythene barrier between Marmox and the mat/SLC is advised? Is this a good idea?

Thanks for any help!
Flash

 

[Time's Ran Out]

Flash - we only have a short time to save the world!
:welcome:
Not got any figures to offer for thermal loss on an insulated garage floor, but was wondering why a 'wine cellar' would need UFH. Room temperature for Red and fridge for White.

 

[flashuk]

Hi

THe wine is expensive and will be stored a long time. Needs to be at 12-15 degrees C. So in winter, room will need a boost of heat to get it to 12C.

F

 

[Alan M]

the problem i see here is keeping the heat out not in.
the temperature in the ground will want to come up and heat your garage (presuming the walls and ceiling are insulated.


10mm of anything will be almost useless.

if i was building this myself i would put in a layer of drainage then 6" of poli iso board insulation and continue that up the walls . continue that up above the ceiling and up to the height of the rolled out insulation . that way you will have a complete thermal envilobe.
i would install a second dor inside the first to creat a thermal air lock. this will reduce the heat escaping.

install your membrains over the insulation. then your UFH and screed.

i would put in a thermal mass system (big lump of concrete that holds the heat) in there incase of ufh or power failure.
there are some great systems coming to market in this area. phase change materials PCM (old concept ) are one of them.
you put the material in a container . as it is soaks up heat from the room it changes from a solid to a liquid. by doing so it traps a lot of energy . when the temperature drops the material solidifies and releases the energy again.
in theory a PCM should hold the energy for ever.

i hear a lot on the radio about wine colecters colections getting ruined because of failure of the heating or cooling systems.
the reason i reconmend the PCM is that the energy will only release when the temp drops . if it releases too much it will get sucked back in and keep everything at the engineered temp (thats the hard part, working it all out)

 

[flashuk]

Thx AlanM

Am not too worried about risk of problems with heat failing as I will have a temp & humidity monitor hooked up to SMS notification if temp goes outside some limits.

Cheers
F

 

[Time's Ran Out]

And I thought it was to drink!

 

[flashuk]

Oh don't worry - a fair amount will get drunk along the way

 

[Uheat - Keith]

If you have the depth, Elektra VCD17 In screed Underfloor Heating Cable, for installing on to insulation boards as Celotex tuff-R, fast-R, T-Break or equivalent, then Cable to be installed in a minimum 50mm screed ( subject to Build Regs ) Like a storage rad system, but you do need 100mm minimum depth to play with.
If you have no insulation in the garage at the moment, 10mm insulation is not going to help much.

Warm regards, Keith