How to keep drinks icy cold or deliciously hot for hours

You might have noticed on our product descriptions for water bottles and some food containers, that we use terms such as ‘single walled’, ‘double walled’, ‘triple walled’ or ‘vacuum layer’.

But what does all this mean?

Well, without getting too deep into the science, here’s a quick rundown:

Single layer insulation

A bottle or food container that has a single layer is just that – one layer of material between the contents of the container and the outside world.

That means that there isn’t too much insulation, so over time, the contents of the container will heat up or cool down to match the outside temperature.

For bottles that start off with cold liquid inside, you might find that your bottle forms condensation as the contents inside cool down the surface of the bottle. That then creates water droplets on the outside of the bottle as they interact with the warmer air.

The benefit of a single layer insulation bottle is that you can fill it with room temperature water and pop it in the fridge, and the water will cool down until it matches the fridge temperature. The drawbacks are that condensation may form, which can be annoying as that can wet the surface it is sitting on.

Double walled insulation, and a vacuum layer

As the name suggests, a container with double walled insulation has two layers between the contents of the container and the outside.

And what’s in the middle of those two layers?

Nothing!

That’s the vacuum part.

So if you add cold water to a double-insulated bottle, it must interact firstly with the closest layer to it, then through the vacuum, then through the next layer, effectively providing three layers between it and the outside temperature.

That means it takes much longer for the cooler inside contents to meet the warmer outside air. Slowing down that process means your water stays cooler for much, much longer (or the opposite, if your contents are hotter than the outside air temperature).

If you have a double walled bottle, then you’ll need to add cold water to start with (it won’t get cold if you add room temperature water then pop it in the fridge), but it will then stay colder for significantly longer.

Triple walled insulation

We think you can guess this one! It’s like double-walled, but with yet another layer!

Like double-walled insulation, triple-walled insulation is designed to slow down the heat transfer process even further, keeping your drinks or food cold (or hot) for even longer.

Which is best?

It’s often down to personal preference.

Single walled bottles are usually lighter, and can be filled with room temperature water then put in the fridge to cool down.

Double walled and triple walled bottles can be slightly heavier, but keep the water cold for much longer (even if the outside of the bottle feels warm to the touch).

For hot drinks/food, generally single walled containers won’t keep your drinks or food hot for too long. But quite often they are microwave friendly so you can heat your meal or drink up in them, saving dishes.

By contrast, double walled and triple walled containers can keep food or drinks warm or hot for hours – but you’ll need to heat the food or drink first before adding them to the containers.

In fact, many find that having both options works best for them, then they have a solution to cover all bases!

Fortunately, we sell a huge range of options, so we’re confident we’ll have something that suits your needs.

The best way to find what you need on our website? Simply type 'single wall', 'double wall' or 'triple wall' into the search bar and browse what comes up!