When packing your cooler with ice or ice packs is it better to put the ice on top of your cooler or on the bottom?
The answer is “it depends”. It depends on what you are trying to keep cold and what solution best suits you. Ideally you want ice or ice packs spread out throughout the cooler – having them on top, on bottom and in the middle. But sometimes you have to choose one or the other.
To keep your items as cold as possible it is recommended that you put your ice or ice packs on the top of the cooler. Cold air sinks so by having the ice at the top the cold will sink down through your food and beverages cooling them as it goes.
Also the majority of the heat coming into the cooler will come from the lid because of the heat from the sun so this adds an extra layer of heat protection to your items.
While other times it can be better to put your ice pack on the bottom of your cooler to keep certain items super cold while allowing other items to stay warmer and dryer.
Why Placing Ice On The Top Generally Works Out Best
Ideally you’d have ice packs or loose ice placed throughout your cooler and around your items. The more ice that is touching your items the colder they will stay, otherwise you will get some items that are colder and some that are warmer.
Generally speaking placing your ice packs on the top of your cooler is going to give you the most even distribution of coldness.
The cold will sink down from the top through the top layer of ice and beverages towards the bottom layers keeping all items in the cooler mostly cold.
This isn’t a guarantee though. If your cooler is extremely tightly packed, items aren’t prechilled and you don’t have many ice packs then the cold may not penetrate far enough to cool all items before your ice packs melt.
The more ice or ice packs you have compared to the items in your cooler the longer they will keep things cold. It’s also a good idea to prechill your items first and keep items you want to stay as cold as possible either at the very bottom of the cooler or touching the ice packs.
The Problem With Putting Ice Packs On Top Of The Cooler
The majority of the heat entering the cooler will come through the top of the cooler.
This happens from sun hitting the lid of the cooler or from the cooler being opened constantly and the top having the most exposure to the warm air when it is opened.
The problem with placing ice packs on the top of the cooler is that they will be exposed to the heat more and thus melt faster than if they were placed on the bottom.
So you have to decide whether you want to keep all your items as cold as possible but for less time or keep a few items super cold for a longer time.
When Is It Best To Put Ice Packs At The Bottom Of Your Cooler?
Sometimes when packing your cooler it actually makes sense to put the ice packs on the bottom of the cooler instead of on the top.
Obviously the items touching the ice packs are going to stay the coldest so when you have items that are very important that you keep cold (eg. meat, ice cream, medicine, milk products) and items further away from the cold pack will be warmer.
Sometimes it can make sense to put the ice packs on the bottom and have items you need to keep cold in contact with the ice packs. Then further up the cooler you can have items that don’t need to be super cold and items you don’t want to get wet, like sandwiches or other food items.
How Many Ice Packs Should You Use In Your Cooler?
How many ice packs you should use in your cooler depends on how long you want to keep ice for.
If you’re just using a little cooler to keep your lunch cold and you don’t mind if it’s warm by the evening then 1-2 small ice packs should do the trick.
If you’re looking to keep ice for much longer, days or maybe even a week then more ice is required. Yeti recommend a 2:1 ice to food ratio but that’s to make ice last for a solid 5-7+ days in a larger cooler.
For most people a 1:2 ratio or a 1:1 ratio of ice/ice packs and food/beverages is going to work just fine.
Or maybe you want to layer your cooler an have a layer of ice bricks on the bottom and a layer of ice bricks on top.
If it was me I would layer ice bricks in between my food and drinks in the cooler and then have a layer of ice bricks on top so everything stays evenly cold. I don’t think I would personally bother with a bottom layer of ice or ice packs.
It’s also important to prechill as many items as possible before you put them in your cooler and if you can prechill your cooler also. Tips like these will help make ice last longer in your cooler.