In order to get the longest life out of your MREs they are best stored at around 60 degrees. So you may have to plan a cooling system for your storage area. Here is an Estimated Life table of most MREs (in F).
Degrees Life 120 1 month 100 18 months 90 30 months 80 48 months 70 55 months 60 84 months
As you can see, 10 degrees of difference between 60 and 70 degrees can mean 29 months! Some MRE sellers say their products last for 7 to 10 years, but that's providing constant proper storing.
Offered by Jon.