Much of the information I've read up until now has stated that "insulation" is the way to reduce temperature change - and thereby reduce our energy consumption. So three candidates were investigate for cost at Home Depot.
* Reflectix "Radiant Barrier" 500 sq.ft. roll
* Insulafoam 4'x8' panel
* Solarflex paint (data sheet) 287 sq.ft. coverage per 5 gallon bucket
Its worth noting that painting would likely have a lower labor cost, and painting reflects the a portion of the heat versus being a barrier to heat.
tc
| product | cost/unit | cost per sq. ft. | cost for 5000 sq. ft. |
|---|---|---|---|
| Reflectix Radiant Barrier | $66/roll | $0.1320 | $660.00 |
| Insulfoam panel | $7 | $0.2188 | $1,093.75 |
| Solarflex roof paint | $70 | $0.2438 | $1,219.51 |
