Some folks on one of the philippines expat forums noted that although thin the insulation was pretty effective.
Foil roof insulation philippines.
The insulation foil face up is supported by a network of 16 gauge galvanized tie wire.
They also went on to note that they thought most of the effect was due to the radiant barrier aluminum foil reflecting the infrared radiant heat coming down from the metal roof.
Bubble insulation roofing insulation.
5 16 nominal thickness of foil bubble insulation highly reflective foil facing acts as 100 vapor barrier dimension 1 meter w x 50.
The holes are positioned so as to leave a 1 2 air space between the foil and the underside of the roofing.
Bubble insulation roofing insulation excellent radiant barrier for heat problem provides maximum efficiency and highest r value for bubble insulation.