Guide: how to choose your sleeping pad?

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The hiking mattress is an essential accessory when planning to hit the road with your bivouac. It adds comfort and improves your sleep. This is what will allow you to recover better and be ready for a new day full of effort. In this buying guide, discover the most important criteria for choosing your trekking mattress as well as the differences between the different models, be they self-inflating, inflatable or foam.

The main criteria for selecting a trekking mattress

While the primary purpose of a mattress is to provide comfort, we are not going to focus on this in particular, as comfort is subjective and specific to each person. There are other criteria to be aware of when making a choice. Indeed, you will need to choose a different mattress depending on your activity: whether a summer hike, the French Grande Randonnée, winter bivouac trip, camping in steep area, etc.

The R-Value, the thermal insulation index

The hiking mattress has two main objectives: to provide comfort but also to protect you from the chill of the ground. To measure the effectiveness of a mattress’s insulation, there is a standard called the R-Value. The higher it is, the more insulating the mattress will be. So, if you are tend to camp in hot areas, it is not necessary to take a mattress with a high R-Value. Conversely, winter bivouac enthusiasts will prefer an R-Value greater than 4.

As you will have understood, being well insulated from the ground is essential when you want to get some good sleep. This does not warm you up, but limits heat loss. If the underside of your sleeping bag is compressed between you the mattress, the insulation it provides will not be optimal. It is therefore the mattress that plays this role.
For a long time, thermal insulation was calculated independently by each manufacturer. Resulting in unreliable ratings. But since 2020, the R-Value has become an international standard, developed by the ASTM body. When choosing the hiking mattress that will follow you for several years, you must therefore compare the R-Value of these, regardless of the brand.
For a bivouac in hot weather (temperature around 15°C at night), a mattress with an R-Value of 1 to 2 will be sufficient. For temperatures ranging from 5 to 15°C, it is advisable to have a mattress with an R-Value ranging from 2 to 4. Finally, for cooler temperatures, choose a mattress with an R-Value greater than 4. These values are indicative, as everyone’s sensitivity to the cold is different.

Manufacturer’s recommendations Thermarest

What size should a bivouac mattress be?

Once the R-Value has been decided, it’s time to move on to the the mattress dimensions. There are two types of measurement: the dimensions when the mattress is unfolded and the dimensions when it is folded.

Does it have to cover the whole body?

Regarding the unfolded dimensions, they are roughly equivalent among all manufacturers. It’s common to talk about size. Most brands offer the following sizes for each of their mattresses:

• Child size: length 119 to 130 cm, width 45 to 51 cm

• Size S (for Small or Short): length 168 cm, width 51 to 55 cm

• Size R (for Regular): length from 183 to 185 cm, width from 51 to 55 cm

• Size RW (for Regular Wide): length from 183 to 185 cm, width from 55 to 64 cm

• Size L (for Long or Large): length 198 cm, width 64 cm

These are indicative sizes. There is no standard on this and each brand is free to have its own size guide.
Regarding the thickness of the mattress, this has no impact on the thermal insulation as mentioned above. It only affects your comfort. Some prefer a thin mattress because it is often lighter and less bulky, while others prefer comfort with a thick mattress. This is particularly the case for side sleepers. When sleeping on your side, your body weight is concentrated on the shoulders and hips, which causes a feeling of ‘sagging’. Having a thick mattress such as the Sea to Summit Ether Light XT therefore avoids having your shoulders touching the ground when you are lying down.

In search of the compact hiking mattress

Regarding the unfolded dimensions, it is generally on these that the hiker focuses. For equal unfolded sizes, some mattresses will take up little space when stored, while others will be very bulky. However, space is every hiker’s enemy. It’s up to you to decide how much space you want for your hiking mattress in your backpack. Some mattresses are smaller than your water bottle, while others won’t fit in a bag. These must then be hung onto your bag.

Example of the Thermarest NeoAir UberLite mattress

A compact hiking mattress comes at the expense of other characteristics: resistance, thickness, and more. Each trekker must judge whether they prefer equipment that takes up space even if it means cutting back on the thickness.

Ultra-light mattresses for more comfort while walking

Finally, the last essential criterion is obviously the weight. With bulk, these are the two points that must be minimised when you are a hiker, at the risk of making the journey more tiring than it needs to be if you’re loaded down with a backpack that is too heavy and too bulky.
To the question ‘how much should a hiking mattress weigh?’, there is no exact answer. As always, it depends on each one. The lightest mattresses weigh less than 300 g. This is the case with the Therm-A-Rest UberLite inflatable mattress. The latter is also one of the lightest on the market. But does it tick the other boxes you are looking for (a high R-Value, very good resistance…)?
The price is also taken into account. Ultra-light hiking mattresses tend to be more expensive because the materials are more expensive. We will conclude this point with the same sentence, which sums up the choice of a hiking mattress: it’s up to you to compare each mattress and make the choice that seems best to you. There are no good or bad mattresses. There are some that are suitable for your use but not necessarily that of your trekking companion.

The secondary criteria of a good hiking mattress

The first criteria we look at are weight, dimensions and insulation. But these are not the only ones. There are other criteria, perhaps more secondary, but which can also be important depending on the hiker you are.

Resistance, a criterion to be taken into account

The first secondary criterion concerns resistance. Today, we are looking for an ever more compact and lighter mattress. The goal is simple: not to encumber or weigh down the backpack. But can this be done at the expense of resistance? Definitely, yes. Some thin mattresses can be pierced quickly on contact with a sharp stone or even a thorn.
You must therefore choose a durable material if you want a mattress that will last the course. For this, we must look at two indicators: the material and the deniers. Nylon is more resistant than polyester, for example. But it has the disadvantage of being heavier. Foam, for its part, has the advantage of being able to be damaged without losing its insulating power. But it is also heavier.

Then, for a mattress with the same material, you have to look at the deniers. A denier is a unit used to determine the thickness of a fibre. The higher it is, the more resistant the mattress will be. Concretely, a 70 denier nylon 6 mattress is more robust than a 30 denier nylon 6 mattress.
In general, if you plan to bivouac under the stars, it is strongly recommended to provide at least a tarp or a footprint under the mattress to avoid contact points between the ground and the mattress. This also helps to avoid soiling the mattress. It is the same for bivouacs in tents. In addition to protecting the latter, you minimise the risk of damaging your trekking mattress.

Noise: for those who are light sleepers

If you are used to nighttime outdoor activities, you know that a mattress can make noise when moving at night. This isn’t a problem for most, but it can be for those who are light sleepers. The friction between the body and the material can cause a slight squeaking noise.
Self-inflating mattresses have managed to counter this noise with a thin layer of velour or foam. But this adds weight. However, it can be a good solution if you want to be sure that you have a mattress that makes no noise.
Otherwise, to avoid creaking and squeaking, you will have to add layers between the mattress and you. Therefore, when you move at night, it helps to reduce these noises. Putting an unused item of clothing between the mattress and the sleeping bag is an example of good practice.

Ease of inflation and deflation

Before we introduce you to the different types of hiking mattresses, you will know that most of them inflate. The advantage of a mattress that inflates is that it is much less bulky since you can fold it.
But it is true that at the end of an intense day of hiking, we do not always have the energy to set it up for the night. Between the tent and the mattress, it takes a few extra minutes which can seem very long, especially when it is raining.
Ease of inflating/deflating can therefore be one criterion to be taken into account. Brands have done a lot of work on this aspect in recent years. Here are the different options you can find on a mattress:

• Self-inflating:

this type of mattress, which we will talk more about later, inflates itself when unfolded. Of course, it will need to be inflated a little more for it to be ready. But it saves some time.

• Optimised valves:

brands are bursting with ingenuity to make inflation easier for you. Most hiking mattresses are equipped with a non-return valve. In other words, when you remove your mouth from the valve, the mattress does not deflate. Other mattresses have two valves: one for inflation, the other for deflation, for the sake of simplicity.

• The electric micro-pump: it takes slightly longer than inflating a mattress by mouth, but takes no effort. You connect it to the mattress and this gives you time to set up your tent or prepare your meal next door.

• The pump bag: more and more brands are delivering it with the mattress. Ultra-light and compact, the pump-bag allows you to inflate the mattress without having to blow yourself into the valve. Save time and energy. (see video below)

How do I use a pump bag?

Otherwise, it’ll be inflation by mouth. Although relatively fast, you still have to be vigilant. The humid air from your mouth can lead to mould and mildew in your mattress, if there is condensation. In cold weather, it could even freeze and impact its thermal performance.

To summarise this first part, here are the 6 criteria to have on your mind about when buying a mattress:

1. Main criteria: lightness, insulation (R-Value) and dimensions (folded and unfolded)
2. Secondary criteria: resistance, inflation and noise.
   Of course, comfort is also of great importance. But unlike the other criteria, it is completely subjective. You have to test to find out or refer to the opinions of hikers who have already tried it.

The different types of bivouac mattresses

Now let’s come to the different types of hiking mattresses. There are three: the inflatable mattress, the self-inflating mattress and the foam mattress. Each has its own advantages and disadvantages. Here they are.

The inflatable mattress, the best weight-space ratio

This is the most popular mattress for hiking. Comfortable, it is above all very compact and ultra-light. In other words, it’s clearly not the accessory that will take up the most space in your backpack. Insulation side, you can go to bivouac him all year round. Some inflatable hiking mattresses have an R-Value of 8. Versatility appreciated by all trekkers.
In terms of its weak points, the inflatable mattress is noisier than its self-inflating and foam counterparts. In addition, it is more likely to be pierced than a self-inflating mattress. You therefore tend to end up with a flat mattress. So you sleep on the floor, without comfort or insulation. By taking care of it, the risks are still low. And if it ever accidentally happens, there are solutions to fix it, such as this quick repair kit (when you are in the field) or this permanent repair kit (to use after you are back home).
To summarise: admittedly more fragile, its weight/size ratio makes it the mattress most used by outdoor enthusiasts.

The foam mattress, resistant and inexpensive

As the name suggests, this mattress is made entirely of foam. The main advantage of this material is its strength. Even in the event of a small scratch, its insulating performance remains the same. In addition, the hiking foam mattress costs less than the others presented.
At the level of its weak points, we of course find its compactness. Unlike the other two, it is more difficult to bend it. Often folded like an accordion, it takes up a lot of space. This is the reason why many lovers of outdoor activities attach it to their backpack as in the photo below.

Accordion-folded foam mattress

Its low thickness combined with the fact that its R-Value rarely exceeds 2 mean that this type of mattress is rarely taken as the only mattress during a hike. It is more often used as a supplement. Remember, the R-Value of two mattresses can add up, many hikers with a 3-season mattress would rather buy a foam mattress to go to bivouac in the winter rather than buy another inflatable mattress with an R-Value greater than 4 or 5 for winter treks.

To sum up: it is common to find hikers who have a foam mattress. But few use it as their main mattress. Generally, the latter is used more as a supplement.

The self-inflating mattress: a mix between inflatable and foam?

Okay, the title is a little exaggerated. The self-inflating mattress looks more like the inflatable mattress than the foam mattress. But it is indeed a middle ground: it is less compact than the inflatable but more than the foam, less resistant than the foam but more than the inflatable, etc.
Regarding its use, you just need to unfold it. To obtain its maximum loft, it should be allowed to inflate. This may still require a few breaths, while being careful of the deposition of humid air. After a day of walking, it’s always nice to be able to kick back and relax. Once the night is over, it deflates, folds and rolls up like an inflatable mattress to store it in the backpack.
In terms of its insulation, it is less efficient than an inflatable mattress. It is still practical for a good 3 seasons of use. In terms of price, it is, on average, cheaper than an inflatable mattress.

To sum up: this is a good alternative for an intermediate hiker.

Comparison of hiking mattresses

To recap, here is a table that compares the mattresses according to the criteria seen above.

This table is for information only. There are heavier foam mattresses than self-inflating mattresses. It is the same for the prices. These are trends but there are air mattresses that are cheaper than foam mattresses. On the other hand, if they are less expensive, this affects other criteria such as insulation (r-value).
On reading this table, we realise that the inflatable mattress is the most suitable for hiking. It is still necessary to qualify! A self-inflating mattress is also suitable for trekking, as is the foam mattress.

In summary

Although the criteria have been categorised into two categories, each person has their own sensitivity, as mentioned a number of times in this hiking mattress buying guide. Insulation should be the basic criterion. If you hike 9 out of 10 times in the summer, it may not be necessary to choose a mattress with an R-Value of 6. For those rare times when you need a mattress for the winter, it may be possible to borrow from your friends, or even rent.
After choosing your R-Value, it is up to everyone to prioritise this or that criterion afterwards. Some ultra-light walkers (MUL) will choose a compact and lightweight hiking mattress while others will emphasise comfort with a large thickness or ease of inflation.
Still, when choosing, you must read the descriptions attached to the products, especially if you buy from an online store. On lyophilise.fr, we make a point of writing complete and factual descriptions. It’s up to you to compare and find the rare pearl that perfectly matches your needs. If you are still hesitating, our teams are available by email or via social networks to answer your latest questions.
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