Nemo Disco 15 sleeping bag review: An excellent choice for side-sleepers

The Nemo Disco 15 sleeping bag delivers excellent sleep quality and smart functionality for a wide range of users – especially those who toss and turn in the night.

Apparently, 70% of people sleep on their side. Which begs the question as to why most sleeping bags are built for people who lay flat on their back all night long. Luckily, there are a couple of outdoor brands who seem to have realised this and are doing things differently.

One example is US gear manufacturer Nemo Equipment, which makes a range of both down and synthetic bags that are very different to the ‘mummy’ shape of most technical sleeping bags.

Instead, Nemo’s Disco down and Forte synthetic bags employ an unusual ‘Spoon’ shape that flares at the elbows and knees. This extra room is designed to allow you to shift position comfortably throughout the night.

It's particularly good for side sleepers who like to tuck up their knees or stick out their elbows. They’re available in men’s and women’s fits, in both regular or long lengths, and multiple temperature ratings, too. The Disco 15 is the warmest option, stuffed with responsibly sourced 650FP down, encased in a fully recycled polyester shell and lining.

Thanks to the brand’s ‘Endless Promise’ initiative, they’re also fully recyclable at the end of their usable lifespan. This makes them among the most sustainable sleeping bags you can buy.

They’re full of clever features to add practicality and versatility for use across the seasons, too. For example, waterproof hood and footbox panels help to protect the fill if you accidentally brush against the walls of your tent (and moisture-resistant down fill throughout adds even more peace of mind).

You also get an integrated pillow pocket inside the hood and lined ‘Thermo Gills’ either side of the torso to aid ventilation on milder nights.

Ethically made using RDS-certified hydrophobic down and 100% recycled fabrics, it also supports full recyclability through Nemo’s 'Endless Promise' initiative, giving it strong sustainability credentials.
When it comes to warmth, the Disco 15 is suitable for spring through late autumn use, with the women’s version offering even greater warmth at the cost of extra bulk.

However, the added comfort and thoughtful features come with trade-offs: it’s heavier and bulkier than many ultralight sleeping bags and slightly less thermally efficient due to the spacious design. So, while not the best option for minimalist backpackers, it’s an excellent choice for eco-conscious campers who value comfort and versatility over weight savings.

Temperature ratings

As a US manufacturer, Nemo primarily expresses the temperature ratings of its sleeping bags and quilts in fahrenheit rather than celsius (centigrade). As its name suggests, the Disco 15 has a lab test temperature rating of 15°F, which equates to -9°C.

Bear in mind that this is the EN/ISO certified lower limit (defined as “the temperature at which a standard man can sleep for eight hours in a curled-up position without waking and feeling cold”). The bag’s comfort rating is 27°F or -3°C (defined as “the temperature at which a standard woman can expect to sleep comfortably in a relaxed position”).

But it’s worth noting that there’s also a women’s version of this bag, which is considerably warmer, with EN/ISO test ratings of 17°F / -8°C (comfort) and 4°F / -16°C (lower). That’s because it has a higher total fill weight, to allow for the fact that due to physiological differences, women generally sleep colder than men (a fact itself reflected in the ISO testing criteria). Downside? It’s considerably heavier and bulkier than the men’s bag (see pack size and weight below).

Still, this means that the Disco 15 is a proper three-season sleeping bag, suitable for use from early spring right through to late autumn. You could even use it in the winter months provided overnight temperatures don’t drop into the minus double digits (Americans please note, we’re still talking celsius here).

Insulation type, fill power and fill weight

The Disco 15 is filled with 650 fill power down. This is low-to-mid range in terms of down fill power (after all, the best bags on the market go up to 900FP+). However, the down that Nemo uses is certified by RDS, the responsible down standard. It's also treated with a PFC-free hydrophobic finish, to improve the fill’s overall resistance to damp and moisture without resorting to harmful chemicals.

These are still warm bags, too, thanks to the generous fill weight. The regular men’s Disco 15 is stuffed with 642g (1lb 7oz) of down, while the women’s regular size contains a whopping 910g (2lbs) of down fill. The long lengths feature 700g/1lb 9oz (men’s) and 1kg/2lb 3oz (women’s) of fill respectively.

Pack size and weight

Lower fill power down means a higher fill weight is required to deliver a given level of overall warmth. And inevitably the more down you use, even if you use lightweight shell and lining fabrics, the heavier and bulkier the sleeping bag will be.

As a result, the men’s Nemo Disco 15F tips the scales at 1.3kg (2lb 14oz) in the regular version and 1.4kg/3lb in the long length. The warmer women’s bag weighs in at 1.6kg (3lb 1oz) for the regular and 1.74kg (3lb 13oz) for the long.

These are packed weights, so you can save 100g or so if you lose the compression stuff sack, but they’re still a bit heavier than we’d like for a three-season down bag. On the other hand, compared to a synthetic bag of similar warmth, they’re considerably lighter and more packable.

The regular sized men’s Disco 15F compresses down to a packed size of 29x21cm when packed inside the included stuff sack. This is bulkier than some, but it’ll still be a viable option for most backpackers. The women’s bag, which is significantly warmer, is a fair bit heavier and bulkier though, which could be a dealbreaker.

Still, when you take into account their generous proportions and excellent comfort levels, many users will consider the Disco 15 to strike a decent balance between weight, temperature ratings and price.

For storage at home, the Disco also comes with a much bigger mesh storage sack. Using this sack ensures you won’t ruin the insulation’s loft by storing the sleeping bag in a compressed state.

Materials and sustainability

As well as that RDS-certified hydrophobic down fill, the shell and lining fabrics of this sleeping bag are made from 100% recycled ripstop polyester that's bluesign approved. Together these give the sleeping bag a soft and comfy feel, and both have a PFC/PFAS-free DWR.

The hood and footbox also incorporate panels of waterproof fabric, which adds an extra degree of reassurance if it’s been damp or humid overnight and your head or feet accidentally brush the walls of your tent.

The Disco series is also part of Nemo’s 'Endless Promise' initiative, which aims to keep gear out of landfill by ensuring products are mono-polymer (built from a single type of material) and fully recyclable at the end of their life. In other words, it has been designed with total circularity in mind.

In the USA you can request a return label from Nemo, post it back to them and they will sort out all of the recycling with their specialist partners. At the time of writing, this service isn’t available in the UK, but it will be launched later in 2025.

Still, as sustainability initiatives go, it’s a laudable aim, and together with the use of completely recycled fabrics and ethically-sourced down throughout, it ensures the Disco has solid environmental credentials.

Size and shape

The key feature of this sleeping bag is its generous shape and internal volume. It's deliberately roomier than most other sleeping bags, with more space at the knees and shoulders for a less-constricted feel. Nemo calls this its 'Spoon' shape, though in terms of profile it’s more reminiscent of a monkey nut or the figure eight.

If you find mummy bags claustrophobic and restrictive, and you want more room to move around naturally at night, this bag might be your ticket to improved sleep in your tent. As a side sleeper, I found it particularly comfortable, offering ample wriggle room.

If you want the numbers, the regular men’s Disco 15F is suitable for anyone up to 183cm (6ft) tall. The shoulder girth is 157cm, the hip girth is 145cm and the knee girth is 155cm. The long version is suitable for people up to 198cm (6ft 6in) tall, and the shoulder, hip and knee girths are 163cm, 147cm and 160cm respectively.

Meanwhile, the regular women’s Disco 15 fits up to 168cm (5ft 6in) with a shoulder girth of 152cm, hip girth of 142cm and knee girth of 150cm. The longer women’s bag has the same dimensions as the men’s regular size (but, as noted previously, a slightly higher total fill weight for added warmth).

These oversized dimensions admittedly leave a fair bit of dead space inside the bag. You’re certainly not cocooned tightly by insulation in the same style as tapered, mummy-shaped sleeping bags. Consequently, we found it takes a little longer to warm up.

All in all, the 'Spoon' is a Marmite feature – some will love the extra room and find it super comfortable; others will find it too loose and potentially draughty. And although there is nothing particularly wrong with this sleeping bag for front or back sleepers, it's clearly optimised for side sleepers.

Features

You get all of the usual features you’d expect: an adjustable hood, a chunky 3/4-length left-hand-side zip with draught-excluding baffle and a two-way zipper. Opposite-sided zippers on the men’s and women’s Disco models allow them to be zipped together into a double sleeping bag. But the Nemo Disco 15 also has some unusual added extras.

The first is an integrated, sleeve-like pocket for sliding in a camping pillow, such as the Nemo Fillo Elite Luxury Backpacking Pillow. This keeps the pillow neatly in place all night.

The second feature is what Nemo call the ‘Blanket Fold draft collar’. It’s a thickly padded insulated flap that acts as an external draught collar, rather than the normal internal draught collar design.

It’s more versatile than the usual approach, since it blocks cold air when folded inwards or mimics the cosy comfort of your quilt or blanket at home when folded down. We really liked this particular feature, but can see that it may polarise opinion. It really depends on whether you like the sensation of being tucked in at night!

The third unique feature is Nemo’s Thermo Gill vents. These are two 50cm vents positioned on either side of the torso, with zippers both inside and outside the bag. The vents are lined with fabric rather than being open, so you can’t stick your arms out of them, for example. But the thin, uninsulated fabric does allow you to micro-adjust your temperature inside the sleeping bag.

We never felt the need to use the vents during our chilly spring testing period, so on many nights they may be surplus to requirements. However, on milder summer nights, it'd add versatility to this three-season bag, extending its useability into warmer conditions without the risk of overheating.

Verdict

The Nemo Disco 15 is a warm, fully featured and extremely comfortable sleeping bag that'll appeal to side sleepers in particular. However, weight-conscious backpackers might find it unnecessarily roomy, as well as overly heavy and bulky for a down bag.

Want a new tent to go with your next sleeping bag purchase? Take a look at our list of the best two-person tents.

About the author

Matt Jones is a freelance journalist based in the heart of Snowdonia National Park, he’s a vastly experienced gear tester and self-confessed outdoor kit geek. Matt’s been one of our main gear testers for the last couple of years and is the first person we call with any complicated kit queries that need in-depth and forensic analysis.