Foaming a regular old cooler

I asked to in the yeti thread, but there be quite the vitriol between 7 or 8 posters in there...... So my bad...




Has anyone that had an old cooler lying around eve try to foam the inside of the walls for keeping ice longer?


Does is work? If so, what kind of foam have you used,







I also understand that refilling the ice is the best way to keep things cold, but we do 5 day river trips where there are no replenish sites, some stretches of river have no known parking along the trip so that option is not available.


We do a lot of techniques. Add frozen water bottles, white towel around... ice the cooler the night before etc. but in 100 deg heat, sometimes that still won't cut it. Even my buddy's yeti kept ice for only two days.