Therm-a-Rest Z Lite Sol vs. NEMO Switchback: The Ultimate Comparison - The Trek (2024)

If you’ve spent time backpacking, I’d be willing to bet my next pizza that you’ve seen either a Therm-a-Rest Z Lite Sol (henceforth referred to as Z Lite) or a NEMO Switchback at some point. Maybe you carried one yourself. Their low weight and price point, combined with exceptional ruggedness, make these closed-cell foam (CCF) sleeping pads a favorite choice of thru-hikers and weekend warriors alike.

For many years, the Z Lite remained the unchallenged monarch of the CCF market and thus came to define the genre. It is iconic. However, for 2019, NEMO released the Switchback, a CCF pad that looks remarkably similar to the Z Lite despite claiming to “redefine the classic closed-cell foam sleeping pad.”

On paper a screen, the two rivals appear to be essentially the same. So which do you choose? Sure, the color choices are different, but do they differ in performance? I snagged one of each to find out.

Therm-a-Rest Z Lite Sol At-a-Glance:

MSRP: $44.95
Type: Accordion-style closed-cell foam sleeping pad
Material: Proprietary, dual-density crosslinked polyethylene
Thickness (measured): 0.75 inches (0.76 inches)
R-value: 2.0
Weight (measured): 14 ounces (14.4 ounces)
Packed size (measured): 20 x 5.5 x 5 inches (20 x 6.3 x 5 inches)
Country of origin: USA

NEMO Switchback At-a-Glance:

MSRP: $49.95
Type: Accordion-style closed-cell foam sleeping pad
Material: Axiotomic, dual-density polyethylene
Thickness (measured): 0.9 inches (0.87 inches)
R-value: 2.0
Weight (measured): 14.5 ounces (14.2 ounces)
Packed size (measured): 20 x 5.5 x 5 inches (20 x 5.4 x 5 inches)
Country of origin: South Korea

Why They’re Popular

CCF pads will never compete with the comfort of an (unpunctured) inflatable sleeping pad, but their other characteristics keep them relevant in an increasingly crowded gear market.

CCF Pros:

Rugged: Compared with inflatable sleeping pads, which become unreliable or totally useless with a pinhole leak, CCF pads can take abuse without degrading performance. The comfort might not be top-notch, but it is reliable.

That said, CCF pads don’t last forever. With extended use, the foam will compress, the comfort-giving dimples will flatten, and the heat-reflecting shine will dull. This is why I choose the word “rugged” instead of “durable”.

Inexpensive: CCF sleeping pads are the cheapest available. The Z Lite and Switchback each cost less than $50 and will save you $100-$200 versus popular inflatable options like the NeoAir XLite.

And again, CCF can’t pop, so you can be sure that your modest investment will be around for the long haul.

Lightweight: At just under one pound, the Z Lite and Switchback qualify as “ultralight” sleeping pads. There are lighter pads out there that even boast higher R-values, such as the NeoAir XLite and UberLite, but those risk quickly turn to deadweight when punctured.

And for shorter hikers or gram-weenies, shortening these CCF pads is an easy way to shave off a few ounces—a difficult, albeit possible, option with inflatables.

Multifunctional: The ruggedness of CCF, combined with the ease of access that comes with strapping a pad to the outside of a pack, make these pads convenient to whip out for trailside comfort throughout the day.

They can double, triple, or even quadruple as a sit pad, yoga mat, or pack back panel, and probably a bunch of other things that my tiny human brain can’t imagine. Let us know in the comments other ways you like to use your CCF sleeping pad.

Easy to Use: Save your breath. Setting up camp is one step easier with a CCF sleeping pad. At the end of a long day on trail, puffing up an inflatable pad is one of my least favorite chores, especially dizzying if I’m at elevation.

The next morning, folding it carefully and rolling it up is equally lame. The contrast with the Z Lite or Switchback could not be starker. They literally take two seconds to pack or unpack, and I legitimately enjoy doing it.

But Here’s The Catch

So if the Z Lite and Switchback are so amazing, why are there so many inflatable sleeping pads on the market? Well, CCF pads, as great as they are, do have their limitations.

CCF Cons:

Comfort: This is the big one, the deal-breaker. The Z Lite and Switchback are 0.75 and 0.9 inches thick respectively, significantly thinner than the 2.5-inch thick NeoAirs. For some backpackers, that is just barely enough. For others, it isn’t even close.

That means campsite selection is crucial for a good night’s sleep when using these pads. And that still only works for the hardiest of sleepers. People who sleep on their backs or bellies will fare better than side sleepers.

That said, I think that sleeping close to the ground is a welcome change from feeling precariously perched on a skinny marshmallow.

Bulk: These pads, even with their ingenious and satisfying nesting-egg-carton accordion form, are huuuge when packed. For that reason, they are almost always carried on the outside of a backpack, which is great for advertising, but terrible for looking sleek. However, for the majority of users, this issue rarely extends beyond aesthetics.

Practically speaking, most backpacks come equipped with one or more ways to strap bulky gear to the outside that are perfect attachment points for keeping a CCF pad handy.

Warmth: Your sleeping pad’s ability to insulate you from the cold ground complements the temperature rating of your sleeping bag or quilt. This is a pad’s R-Value, given on a numerical scale from 1 (least insulating) to 7 (most insulating).

The Z Lite and Switchback both have an R-value of 2.0, which is on the low end of being suitable for three-season excursions. For comparison, many inflatable pads boast R-values closer to 4.0 or more. Skimping on your sleeping pad R-value will stretch the limits of your sleeping bag temperature rating, which is measured using a sleeping pad with an R-value of 4.8 (ISO 23537).

Of course, comfortable sleep temperature is highly dependent on the individual. The Z Lite or Switchback might work perfectly well for warm sleepers even when the mercury drops. It is important to understand your own body and to look at your sleep system as a whole.

Note: R-value is additive, meaning that you get to add the R-values of stacked pads. This makes CCF pads a great addition to boost the warmth of an inflatable pad on winter trips.

Durability: While CCF may be rugged, I hesitate to call it durable. It can handle punctures, but heavy use will compress and deform the material over time, just like the midsole of your favorite trail shoes. Conversely, inflatable pads can’t handle punctures but will maintain performance and comfort for many years if leaks are avoided.

The Z Lite and Switchback rely on their dimpled shape (traps warm air) and a reflective layer (reflects body heat) for comfort and warmth. Both of these will degrade with use, even if babied. That already low R-Value may dip lower with extended use. That marginal comfort might become more suspect.

Unfortunately, neither Therm-a-Rest nor NEMO were able to provideany data about long-term performance degradation, particularly R-value, but expect that the warmth and comfort won’t be the same at the end of a thru-hike as they were on day one.

Therm-a-Rest Z Lite Sol vs. NEMO Switchback

These sleeping pads are eerily similar. Both share the same rectangular footprint (72”x20”) and dimpled accordion construction. Both are made from dual-density CCF and a warmth-boosting reflective surface that works to achieve identical 2.0 R-values. However, there’s more to it than that. Let’s see how they compare on the things that matter.

Side-by-Side Comparison

Weight

Official specs from Therm-a-Rest and NEMO, give the Z Lite a tiny, half-ounce advantage in weight over the Switchback. However, using my own scale, I found this to be the opposite of reality. The Z Lite came in overweight at 14.4 ounces. The Switchback was underweight, and less than the Z Lite, at 14.2 ounces.

I think this says a lot about manufacturing variability and does little to inform consumers about which pad is a better choice.

I’d be willing to bet that weighing a second pair of Z Lite and Switchback would yield different numbers. The tiny variance in weight (<0.5oz) is so minimal that it borders on insignificant.

Long story short, weight is not a distinguishing factor between the Z Lite and Switchback. If a small fraction of an ounce matters that much to you, perhaps try taking a pair of scissors and rounding out the corners of whichever pad you choose.

Comfort

Based on thickness alone, the Switchback appears to have a comfortable advantage. NEMO also throws around some fancy terminology like ‘hypnoelastic zone’ to legitimize their claim to superior comfort. However, I was skeptical that I would be able to notice any difference at all between the Z Lite and Switchback, so I enlisted the help of my partner, SpiceRack, to conduct a very scientific blind comfort test.

Blindfolded, and wearing ski gloves and poofy socks, we lay on each side of each pad, placed on a hard, composite deck. The order was picked at random by the unblindfolded person. Not only was this fun, but it was amazingly informative.

The result? The Switchback was shockingly more comfortable than the Z Lite. SpiceRack and I guessed right every single time. The difference in comfort was that obvious. While I didn’t bottom out regardless of sleep position on the Z Lite or Switchback (I’m a small dude, and results will vary), the Z Lite was significantly less friendly to my hip and ribcage while I was on my side.

Both pads supported my weight, but the Switchback did it comfortably and the Z Lite hosted uncomfortable pressure points. Even on my back and belly, the Switchback felt significantly thicker with more cushion than the Z Lite. Honestly, I thought this test would be a wash. We were both surprised by the clarity of the result.

Other observations:

• We agreed that the colorful side of each pad was grippier than the silver side, which made it slightly more pleasant to lay on. SpiceRack was big on this point because she sleeps in strange contortions. I hovered near indifference while still acknowledging the phenomenon.
• The insulating properties of each pad were obvious when our elbows hung over the edges, above the cold deck surface.
• The new pads were noticeably more supportive than our ratty Switchback sit pads that we carried, sat, and slept on for half of the CDT in 2019. The new Switchback was better all round. The Z Lite provided more, yet harsher support than the old Switchback, which allowed us to feel the hard deck below.

Packability

Although Therm-a-Rest and NEMO list the same packed size for their pads, the Switchback is the clear winner. It folds down to 5.4 inches, unaided. The Z Lite, on the other hand, puffs up to 6.3 inches. Chalk that discrepancy up to a broken ruler at Therm-a-Rest if you want.

Both pads can squeeze a bit smaller, but the unique dimple pattern and shape on the Switchback indisputably nests better with less wasted space, despite their extra thickness. Does that extra inch matter when the pad is strapped to the outside of a backpack? Probably not, but I wish Therm-a-Rest would fix that dang ruler!

Durability

Neither the Z Lite nor Switchback will pop if you drop your knife on it. That’s the good part. CCF pads are reliable if nothing else. Unfortunately, comfort does degrade with use, and both the Z Lite and Switchback are susceptible. That’s the bad part. Like I said above, I wish I had some hard data to quantify this effect, but instead, what I have is merely anecdotal.

CCF pads look thrashed after a long thru-hike. SpiceRack’s PCT Z Lite wasn’t cutting it on the CDT so she replaced it, and my CDT Switchback just isn’t the same anymore. The support of the dimples is severely degraded, though the foam is still comfortably squishy. With that said, based on the comfort test, the Switchback is starting at a place of higher comfort, so perhaps its ‘thrashed’ comfort is better than that of the Z Lite.

Warmth

Both the Z Lite and Switchback have a tested R-value of 2.0. That number is on the low end of being suitable for three-season use. Both companies helped develop the ASTM F3340-18 testing standard used to produce these numbers, which is a quantifiable and the least subjective way to compare sleeping pad insulating performance.

If you want to know more about R-value and how it’s tested, here is a thorough explanation from Therm-a-Rest and NEMO. Unlike with inflatable pads, I am suspicious that the R-value of the Z Lite and Switchback degrades with use.

Price

Like the weight difference, the price gap between the Z Lite ($44.95) and Switchback ($49.95) is marginal, barely enough to buy a cheap burrito. Whichever pad is currently on sale could be the deciding factor here. With either option, you can save $10 if you’re willing to sacrifice 21 inches and four ounces by purchasing the short size. Whatever the pad or size, these prices are hard to beat.

Color

The Z Lite comes in Limon (yellow) and Blue (blue). The Switchback is available in Sunset Orange (orange). Hiking during hunting season? Choose yellow or orange.

Country of Manufacture

For the American market, all Therm-a-Rest sleeping pads are built in the USA, using potentially imported materials. This is a point of pride for the company, as it says it benefits both the environment and product development.

NEMO manufactures the Switchback in South Korea, not the worst and not the best. From what I can find, NEMO takes sustainability seriously and has completed the Higg Index, which evaluates environmental impact throughout the supply chain. Therm-a-Rest also uses the Higg Index to inform process improvements.

Reflective Side Up or Down?

Both the Z Lite and Switchback have a shiny, metallic layer on one side. Therm-a-Rest claims this boosts warmth by 15%. NEMO doesn’t quantify the benefit, but the companies agree that it works by reflecting radiant heat back to the body. Curiously, each company provides different instructions about which side points up, and which side hits the dirt.

Therm-a-Rest instructs using the Z Lite reflective side-up. NEMO says the metallic film points to the ground. In a lab setting, I bet it doesn’t make a difference, but I think it might in the wild.

The outer reflective layer dulls with use, even if it never touches the ground. The Z Lite depends on that easily tarnished layer for warmth, whereas the Switchback relies on the other side of that shiny layer. The internal side still reflects radiated body heat even though it can’t be seen, but it is protected by the orange foam and, therefore, potentially remains shinier and more reflective for longer. It also turns the whole pad into a heat sponge that retains body warmth.

The fuzzy remnants of my engineering degree tell me that NEMO has it right, but heat transfer was far from my strongest subject. However, my recommendation is to follow the manufacturer instructions. That’s how the pad was designed to be used, with the most abrasion resilient side down. Whatever you do, just remember to be consistent or risk getting your sleeping bag covered in sap and/or mud.

Final recommendation

If you made it through this article, you won’t be surprised to read that I recommend the NEMO Switchback over the Therm-a-Rest Z Lite Sol. And believe me when I say that I was amazed that I formed such a strong opinion about a seemingly inconsequential subject.

The Switchback is simply a better pad. The boosted comfort might be the most important difference, but I appreciate the better-than-advertised weight and packed-size. It is clear that NEMO put a lot of nerd power into improving on an icon, and it paid off.

However, even with clear differences, the Z Lite and Switchback are closely matched. Also, I’m willing to admit that I may undervalue the environmental benefits of manufacturing in the USA rather than in South Korea. After all, there are few causes more important than preventing excess harm to our planet

And remember that these CCF pads share a polarizing list of pros and cons versus inflatable sleeping pads. As always, I heartily recommend trying out any new gear if you can. Even the more comfortable Switchback might remind you of thin cardboard. But if you do choose one of these sleeping pads, wear it on your pack proudly, and measure the joys of the backcountry by the fading shine of the silver side.

Shop the Therm-a-Rest Z Lite Sol

Shop the NEMO Switchback