Boat Cooler Basics

Nothing shouts Summer Boating! like an ice-cold drink on a sticky-hot day. But if you find yourself short of ice after a long day on the water or constantly shelling out for a fresh bag from the dockside store each morning of a long weekend, you may need to upgrade your chill chest. Four factors determine the effectiveness of your cold spaces aboard: Size, insulation, gasketing, and drainage. Let's tackle them one by one.

Size

Bigger isn't necessarily better. The more volume your cooler or insulated box has, the more ice you'll need to chill down all the stuff in it, and all the air in any empty space. This is why a full cooler holds ice better than one that's mostly empty — you're not wasting thermal energy cooling down all that air, some of which, by the way, gets exchanged every time you open the lid. The ideal cooler or box will be just big enough for your normal weekend's use. If you need more space on occasion, you can always employ a soft-sided cooler bag as needed.

Insulation

This might seem obvious, but more is better in this case. Ideally, it's thick foam, and the lid is as thick as is practical. If you don't have an insulated box on board currently and you're considering adding insulation yourself, the first consideration is how much space there is around the box (on all sides) to add foam — without it contacting the hullsides or the bottom of the boat. The second issue is drainage.

Gasketing

Just like the weather stripping around the doors of your house, a good thick gasket prevents air from leaking in or out of your cooler, in this case, stealing your precious cold air and melting your frozen H2O. If the lid of your box or cooler doesn't have a gasket, consider using a $4 roll of foam tape or door kerf to seal the gap. It won't hold up as well as the proper rubber gasketing of a high-end Yeti or Engel cooler, but it should get you through a season or two.

Drainage

Yes you need to be able to drain your box or cooler, but not at all times. You want a removable plug so you can spill excess water and weight at the end of the weekend, or leave it open to melt and drain in your absence, but until then, that chilled water is your beverage's best friend. Water transfers thermal energy way more efficiently than air, so when your ice melts and becomes an icy bath, your drinks will never be colder. The flip side of this is that your sandwich will never be soggier. But rather than drain that cold water away to keep your foodstuffs dry, pack them in zip-top bags instead.

If you're considering adding insulation to a box on board, make sure it drains overboard, but also figure out how you're going to plug that drain while the box is in use. And while you're at it, figure out a way to stow the plug so you always know where it is when you need it on Saturday morning.