Cheap insulation. Is there such a thing?

Just some info on heat block products. Look carefully at emissivity (e) big word alert! It is "the relative ability of surface to emit energy by radiation." Low number like .1 to .2 good; high number like .8 bad. The Reflective Insulation Manufacturers Association (RIMA) establishes standards and rates Radiant Barriers....according to STS Coatings they are rated #1 by RIMA. i have visited their facility and talked to old farmers around here who have used their product and I can recommend them...hey, maybe they're looking for distributors in GA...you could be RadiantRustyRatRod! Sorry, been a long day.

I looked at PPG info above and saw e of .8--this is bad...hopefully a misprint or I'm messed up. But I was equally not impressed with how little heat it reflects and how after 3 years it's even worse...wouldn't waste my money on that. You can have something that reflects well, but if it HEATS up and allows the heat to pass through it into your shop (high emissivity) your going to be feeling the heat! This is why it can be 100 outside and 130 in your metal shop...the metal roof with high emissivity let's through energy which will heat objects above the outside air temperature based on the metal properties present.

The bubble wrap stuff with aluminum on either side sounds cool...and the Free insulation. A combo where the sun hits hardest would really help for the least $$. The radiant heat barrier won't hurt if down the road you decide to insulate and air condition...in fact, it'll lower your electric bill considerably. I give radiant heat block a thumbs up for cost and simplicity...if I was going to work in there everyday I'd insulate and a/c, but I was on a budget and started w/ heat block as a foundation. Just my 2 cents. Good luck with whatever you decide!