This isn't my idea, but I tripped across it in a YouTube video.

I took a trip up to Sawbill Campgrounds last weekend with my teardrop trailer and I had been thinking about how to increase the insulation value of the Coleman ice cooler that I carry in the galley area of the trailer. I had thought about building box of foam construction insulation, but just don't have the extra room around the cooler.

What I came upon is that the cover of my Coleman cooler was not insulated. I'm guessing the covers of most of the Coleman and Igloo type of inexpensive coolers are not insulated.

What I did was drill a number of 1/4" holes into the cooler cover from the bottom. You need to drill enough holes that you can easily fill the void in the cover with expandable insulation foam that you get at the hardware store. You want enough holes that you can get the straw into them and aim the straw in a few directions. The holes not only allow you get the foam into the cover, but also allow the overspray to easily escape back out.

Make sure you let it harden before you cut the expanded foam from the holes.

I noticed a sizable difference in how long my had ice in the cooler.

I tried this with a generic hollow lid equipped cooler and the foam condensed back into liquid before it hardened. The cooler was ruined. I felt it was a great waste...Lots of other places I could have used that spray foam. ;)

OCDave: "I tried this with a generic hollow lid equipped cooler and the foam condensed back into liquid before it hardened. The cooler was ruined. I felt it was a great waste...Lots of other places I could have used that spray foam. ;)"

What was the temperature when you sprayed the foam? I use spray foam everyday at work and have never had it "condense back into liquid." When it is -20 it takes a long time to harden, but still expanded into foam.

I cut a piece of closed-cell foam and taped it to the inside of the cover. I'm not sure whether it helps or not, but I figured it can't hurt.

MidwestFirecraft: "What was the temperature when you sprayed the foam? I use spray foam everyday at work and have never had it "condense back into liquid." When it is -20 it takes a long time to harden, but still expanded into foam. "

Normal ambient summer temps. It was older, used cooler. I suspect there was grease, veg oil or something that contaminated inside of the lid. Something that reacted with the foam and prevented it from bonding with the plastic??? I don't know. Can't explain why but, it didn't work for me.

I covered a cooler in bubble foil insulation once. Really increased the performance of the cooler.

That's a good tip, to spray insulating material inside the hollow lid. I also have a reflectix cover that I cut to fit the inside of the cooler to minimize the amount of space that needs to be cooled, and it then lets me separate things which might be damaged sitting against an ice pack.

mirth: " I also have a reflectix cover that I cut to fit the inside of the cooler."

I made a reflectix liner for my main soft cooler that includes a flap over top and can tell the difference in ice retention. I take the hard plastic liner out so i can flex the cooler to squeeze it in tight spaces and the reflectix liner flexes well also.