Radiant Heat Panel color (any difference?)

[jdwill100]

I am making some underfloor radiant heat panels out of aluminum sheeting that is pre-painted white in color on one side and brown on the other side. The panels will be attached to the bottom of the subfloor with PEX in a groove on the topside of the aluminum. Should I face the brown or white side of the plates toward the top floor or would it not make any sort of difference? Thanks for any thoughts in this matter.

[homebild]

Won't matter.

Aluminum is a highly conductive material and will transfer the heat from the PEX easily through the metal down and to the air space below.

What is more important in your design is not the aluminum at all, but how much insulation you will install below it to keep the heat moving up to the floor above.

In most cases you will need at least an R-25 amount of insulation below the heat panel for it to be maximally effiective.