The blogosphere of backpacking and camping is flooded with a humdrum of articles and guides with gear tips on choosing the right tent, boots, and whatnot. But with the growth of available information, the substance of the advice you get is diluted.
It seems like everybody is making list-type checklists, re-mulling the same information over and over. It’s information that already lives under the hat of any half-seasoned backpacker, and it comes down to commonplaces like “choose what’s right for you.”
Today we right that wrong, well, at least in one area that we feel has been silently evolving without most of the community taking notice – getting proper sleep on the trail.
Two areas we’ll focus on:
- R-value – what it means and how our perception of it should be changing to keep up with the evolving industry
- When a full-on air mattress might be an option for a backpacker and how to choose right
Where you can go wrong
It’s easy for an experienced backpacker to simply rely on the body of knowledge and experience they have and there’s nothing wrong with the approach.
The issue is this – the industry of sleeping gear has changed significantly over the last few years.
If you are still going “with that yellow one you like from that brand you trust,” it might be time to freshen up what we know about choosing a good sleeping pad or an inflatable mattress.
Let’s be precise
We all know the old ‘un “Give a man a fish…teach a man to fish…”
It would be easy to just recommend products – the problem with that is that there’s too much we don’t know about your circumstances.
We can’t know whether you’re backpacking alone or with a partner, we can’t know the specifics of the trail you’re about to tackle, the shape you’re in…there’s just too many variables.
The confusion surrounding the R-value
Let’s be honest – not many people fully understand the elusive R-value of a pad, and that’s not a surprise since the very concept, useful as it might be, is unclear.
Did you know that there is no set standard on how to measure R-value?
Without going into the nitty-gritty of it all, this means that comparing sleeping pads across brands based on their R-value is, at best, imprecise.
Let’s do two things here:
- Define what an R-value and how modern technology has changed it
- Look at what that means for your plans
What is R-value and why our perception of it should evolve with the times?
R-value is simply a measure of how good your pad is at insulating you from the ground.
Yes, most of us inherently know the definition but do we understand it?
Let’s look at a few questions as an example:
- What’s the R-value of two pads stacked on top of each other?
- If you had two pads of different R-values, how would you stack them for maximum insulation?
- How do you stack the R-values of a pad and a sleeping bag to get the most out of the combo while minimizing the weight?
- Should the choice of the pad be adjusted to women and if yes, how?
If you know the answers to all the three questions above, kudos…you can simply skip this section altogether.
However, if you have doubts, stick around for a minute.
R value is linear
The formula for calculating the R-value is R = I / lambda where the “I” is the thickness of the material and the “lambda” is the thermal conductivity.
Don’t worry about the formula, think about what it means
Knowing the formula for the R value is not going to be of much help when planning a hike.
The takeaway should be this – to get the R-value you’re aiming for, you can simply add-up the two numbers (like the R value of your pad and your sleeping bag).
Obviously, there will be some marginal thermal conductivity loss, but it’s nothing you should be worried about.
Let’s simplify it
What we said above means that if you have a pad with an R-value of 3 and a sleeping bag with, say, an R-value of 2.5, the combo has an approximate R-value of 5.5.
Once you know that and you know what temperatures you can expect on a brisk night, it becomes easier to shed weight by planning the R-value of your sleeping combo right.
What this means in real-life
Let’s take an example we can relate to. Let’s say that you’re planning a fall hike on a trail that gets chilly at night, like the High Sierra.
Most of us would adjust the choice of the sleeping bag and go with that goofy, bulky winter bag instead of the slick 3-season bag. Surely, going with a different pad would add much more weight, right?
Here’s the important part – the evolution in the materials used for sleeping pads in last few years made it possible to “jump” from an R-value of 4 to 7 with the difference in weight being as small as a few ounces.
Bottom line – if you’re not on top of what’s going on in the sleep gear industry, you’d think that getting better insulation by choosing a different pad means much more weight added.
Those days are gone.
The race in the industry and why it’s good for us
Recent years in the sleep gear industry have been less about introducing new materials and more about new solutions for the inner design.
Remember that formula for the R value? Well, the trend in the industry is been all about improving on the denominator in that equation – the thermal resistance.
To make our point here, let’s take the example of the Triangular Core Matrix technology.
Instead of going with a thicker material or more of it, the technology focuses on packing more layers of triangular chambers into the pad.
The bottom baffle layers “absorb” most of the cold while the top 2 layers minimize the loss of energy created by the warmth of your body by using materials that reflect it back towards you.
The bottom line
The example above is just that – an example, and there are many innovative approaches to the inner design that yield similar results – higher thermal insulation with little weight added.
That’s where the industry race is, and the results range from small improvement to outliers – some of the modern pads have 3-4 times higher R-value while being much lighter.
As far as we are cornered, the trend is great as it means less weight and bulk on our shoulders.
A camping air mattress – is it an option for a backpacker and how to choose the best one?
For most backpackers, replacing a sleeping pad with a full-on inflatable mattress is rarely an option.
They are too big, weigh too much and take up too much space. Right?
That’s changing too and the scenarios where a comfort of a blow-up mattress is worth the added weight are more common than they used to be.
The main reason lies with the fact that the gap between the weight and bulk of a sleeping pad and a good camping air mattress is getting smaller each year.
Bottom line – there are models out there that pack small and are light enough to be used for backpacking.
When is it an option?
Let’s not get ahead of ourselves here – even the lightest and the best camping air beds are still only an option for lighter hikes with a partner (when you have two backpacks available).
The lightest camping air beds are still 5-6 lbs, and you still have to think about the pump (usually battery-operated).
This means that even for the lighter, shorter hikes you still have to know your stuff to choose right.
What a backpacker should look for in a good camping air mattress
The criteria for choosing the best air bed for the trail is not going to be the same as choosing a camping air bed that would be used if you’re driving to the site.
Here are a few rules of thumb:
- Choose chambers and coils over air beams (the more chambers, the better)
- Look for a model with a small compact pump (usually run by 4D batteries)
- Think about the material – PVC vs. TPU
The reason even the best air bed might not give enough insulation, and you might feel the cold rushes on a chilly night are the micro-currents of cold air swirling inside the mattress.
A chambered designed minimizes the air movement inside the mattress and thus, reduces the cold micro swirls of air. With beams, the air moves inside “as it pleases” and more air movement means less insulation.
PVC vs. TPU camping air mattress
Most camping air beds are still made using some form of PVC.
In a worst case scenario (like you’re the bed getting punctured or developing a leak in the middle of the night) you’ll wake up to a useless piece of plastic. Finding the leak and patching it up on-the-go is rarely as simple as it seems to be in the instruction manual.
On the other hand, you have TPU air mattresses. These were designed for the small chunk of the market that’s still worried about the health hazards of PVC.
That’s not what we’re concerned about here. A backpacker should go with an inflatable bed that will minimize the chance of air leaks.
In those terms, the advantage of TPU is clear – the material is more resistant to punctures, it doesn’t stretch as much (so there’s less of a chance of developing a leak at the seams), and finally, it’s lighter.
Bottom line – there are scenarios when a good camping air mattress is a viable option, but for more serious hikes, a backpacker will still stick with a sleeping pad.
Back to you
As we said from the beginning, the purpose of this guide is not to tell you what to get. It’s to awaken those of us who are still unaware of the massive changes the sleeping gear industry has seen in recent years and make sense of it all.
Safe trails and sweet dreams.
This article was published in partnership with The Sleep Studies.