[H. L. Chauvin]

It is too long a subject to explain; however, if one were to go on line and research "Radiant Barriers", (which has been around since the 1920's), and try it, one would be convinced of the benefits of aluminum radiant barriers, (which can reflect 97% of radiant heat), "only" when placed adjacent to an "air space".

It can also provide a Low-E condition by reducing heat emissions by 97% when placed adjacent to an air space.

Aluminum foil sandwiched between 2 pieces of cardboard, carpet, plywood, steel, etc., reflects zero (0) heat.

Sound transmission, measured with a sound transmission coefficient, (STC rating), is greatly reduced when an air space is added and mass is added to one of two adjacent materials; hence, a similar minimum 3/4" air space can be used for both sound transmission reduction and radiant heat reduction.

One great solution for Model A "interior cab" heat transmission reduction and noise reduction is to:

1. First, adhesively apply and add two (2) layers of foil faced sound deadening material to the in-side of the thin metal firewall. (Double layer produces 3 times the sound deadening effect, thus adding mass to one adjacent material for sound reduction, plus a layer of foil for low heat emission).

2. Second, prior to installing the firewall assembly indicated in reply #3 above, at every pre-drilled hole in same, (for bolt fasteners), provide a 3/4" x 3/4" x 1-1/2" long wood block on top of the foil faced sound deadener listed in (1.) above. (This 3/4" created air space is the key to additional loss of sound transmission and 97% reduction in heat emissions).

3. Lastly, provide the firewall assembly indicated in reply #3 above, where the dense fiberglass backing is exposed to the created 3/4" air space to absorb lesser amounts of sound coming through the thin metal firewall because of adding mass to said firewall.

4. On the underside of floor boards, "thoroughly" remove all petroleum products and dirt, sand smooth and paint same with two coats of paint; then adhesively apply one layer of Lowe's or Home Depot's aluminum duct tape, which will be exposed to air & can reflect 97% of muffler radiant heat and hard surfaced highway heat.

5. Have only been experimenting with this stuff for over 40 years on about 2-3/4 million square feet of public buildings, and really, still learning ...... some manufacturer's insulation continuing education seminars offered today are really a joke.