Insulation / Sound deadening
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Reflectix is a very good product that I've used many times but it is not very useful in a car interior.
Those high r-values are "apparent" values that only occur in very specific circumstances much more common in a lab than in the real world.
Installed between the floor pan and carpet its R-value is essentially that of an air gap of the same thickness. Air gaps are excellent insulators but 1/4" or so just isn't much thus that R 1.1 or so "true" insulation value. Also it has no sound attenuation ability so there are better things to use.
Against the firewall and transmission "tunnel" however is another matter. While it would be much more effective installed on the engine side of the firewall and the underside of the tunnel (both impractical/impossible/destructive to the insulation) it will at least stop some radiative heat transfer.
Exterior insulation of HVAC ductwork installed in non-conditioned space is one of my favorite uses for reflectix. It is time consuming to apply but it is extremely effective as confirmed by my tests.
Those high r-values are "apparent" values that only occur in very specific circumstances much more common in a lab than in the real world.
Installed between the floor pan and carpet its R-value is essentially that of an air gap of the same thickness. Air gaps are excellent insulators but 1/4" or so just isn't much thus that R 1.1 or so "true" insulation value. Also it has no sound attenuation ability so there are better things to use.
Against the firewall and transmission "tunnel" however is another matter. While it would be much more effective installed on the engine side of the firewall and the underside of the tunnel (both impractical/impossible/destructive to the insulation) it will at least stop some radiative heat transfer.
Exterior insulation of HVAC ductwork installed in non-conditioned space is one of my favorite uses for reflectix. It is time consuming to apply but it is extremely effective as confirmed by my tests.
