Headliner construction
 

I am finally building a headliner for the Jeep's hardtop.

I am using cardboard with headliner material on the inside & a layer of aluminum foil for a radiant barrier on the outside. The question I have is which direction should the shiny side be facing, toward the cab or the sky? It is more to keep heat in than out.

Thanks

Don

depends on whether you want to keep "them" from beaming thoughts into your head, or keep "them" from reading yours...

my guess is shiny side in.

The shiny side must face an air space. Otherwise it doesn't do anything. Theoretically, it doesn't matter if the shiny side is facing up or down, as long as it is facing an air space. Practically, dust tends to collect on it if it faces up, which degrades its performance. So down is probably preferred, as long as it faces an air space. It is usually recommended that the air space be at least 0.75 inches deep to get the full performance specified for radiant barriers.

Search "radiant barrier" to confirm this and for more info.