Garage door insulation FYI

[Pirate]

Just finished insulating our overhead metal garage door.
Used 3/4" foil on 1 side, insulation board.
With the foil side against the metal door, the temperature reduction, in direct FL sun was 13 degrees.
With the foil side spaced 5/8" from the door, the temperature reduction was 14 degrees. I thought with the 5/8" air gap it would be better.

[daddo]

The Florida sun is different than the rest of the country.  Has something to do with the azimuth parithim ismuth thingy.


 Air gaps reduce conduction at contact points but you still have convection. Moist air increases convection.

[frule]

Just finished insulating our overhead metal garage door.
Used 3/4" foil on 1 side, insulation board.
With the foil side against the metal door, the temperature reduction, in direct FL sun was 13 degrees.
With the foil side spaced 5/8" from the door, the temperature reduction was 14 degrees. I thought with the 5/8" air gap it would be better.

When you say temperature reduction, do you mean ambient temps in the garage, or surface temps on the door?

If the ambient temperature in the garage dropped by 13-14 degrees, that seems like quite a positive gain.