Blog

20 years ago, whether you were a man or a woman you bought a ‘sleeping bag’, these days there are gender specific sleeping bags available so you would buy either a man’s sleeping bag or a woman’s – or would you? We’re not sure, so this article is about the differences, why is a woman’s sleeping bag different, and are those differences important to you?

We have female customers who buy male or unisex sleeping bags, and we have male customers who buy women’s sleeping bags – because the particular feature set is best suited to them as an individual.

Let’s take a look….

Shape
In general terms women have wider hips and narrower shoulders than men and some manufacturers have used this generalisation to inform the design of their female specific sleeping bags, designing them to be wider at the hips and narrower at the shoulders than the male specific bag.

Length
A common difference between the male and female versions of particular sleeping bags are length. On average women are shorter than men so manufacturers may size their men’s ‘Regular’ sized bag to fit men up to 6ft, while their women’s specific version of the same bag may be sized to fit a woman up to 5ft 6inches, so, if you are a five foot 10 inch woman you need to be shopping either Regular Men’s bags or Women’s Long bags – but that doesn’t apply to all manufacturers – to make an informed choice you need to know what the manufacturers policy is.

Amount of Filling
Another common belief is that women feel the cold more than men – this is really subjective because there are so many factors which affect whether you feel cold or not, even down to whether and what you have eaten recently.

Subjective or not though this has influenced the design of women specific sleeping bags with many manufacturers putting more down into the women’s specific bag than the equivalent man’s.

This isn’t always obvious however, two gender versions of the same sleeping bag may differ in length by 6inches, and on paper they have the same amount of down in the bags (known as Fill Weight), but because the overall volume of the bags differ you can say that the women’s bag has a higher density of down and will therefore provide more warmth.

Adding filling into synthetic bags is more problematical, since synthetic insulation is commonly in ‘mat’ form you would have to get a slightly higher thickness of mat in order to make equivalent bags, such a product will probably not be available.

Some synthetic fill is ‘loose fill’ like down, you could add more insulation to a sleeping bag if the filling is in this format.

Location of Filling
Another commonly held view (don’t blame the messenger) is that women have cold feet, some manufacturers have taken this on board and put more insulation into the foot box at the expense of other areas. This may be an important feature for some women but I’m sure not everyone.

EN13537 testing
At Ultralight Outdoor Gear we believe that the EN tested rating for a sleeping bag is a useful tool to compare how a range of sleeping bags will preform against each other. You can find a full description of how the testing is carried out here.

For our purposes it’s worth noting that the Comfort Limit rating is the limit at which an average man will not feel cold when occupying the sleeping bag, wearing a base-layer top and bottoms, and lying on a reasonable sleeping mat.

However the Comfort rating (rather than the Comfort Limit rating) is the same threshold for a woman – so, it is the temperature at which an average woman will not feel cold when occupying the sleeping bag, wearing a base-layer top and bottoms, and lying on a reasonable sleeping mat.

Therefore, if you are a woman shopping for a sleeping bag you should look at the Comfort rating rather than the Comfort Limit rating as an indicator of how warm the sleeping bag will be.

All the above comes with a hefty caveat – it refers to the average man or woman. Feeling hot or cold depends on a range of factors including an individual’s metabolism, you may already have an idea of whether you generally sleep warm or sleep cold.

Which manufacturers have taken which view?

Sea to Summit
The backbone of the Sea to Summit sleeping bag range is the Men’s Spark sleeping bags and its Women’s specific version – the Flames. These are high performing sleeping bags which tend to be close fitting and are made from super lightweight materials.

The Flame bags are wider at the hips and narrower at the shoulders and there’s extra down in the women’s version. Sea to Summit make the Regular Women’s bag to fit women up to 5ft 7ins and the Regular Mans bag to fit men up to 6ft.

A quick comparison of the key specs demonstrates this:

In this case the same sleeping bag (in two versions) is suitable for Men down to -2C but for Women only down to +2C – a 4 degree difference. This difference has found its way into the specification because of the EN testing regime specification.

Rab
Rab make their women’s sleeping bags shorter than the men’s and the inner girth is 4cm shorter at the shoulders. Both the men’s and women’s versions of a particular bag have the same amount of down, but because the women’s bag is shorter there is excess down which is redistributed to the core warmth areas and the footbox.

Taking the intended interpretation of the EN test results means that a Man’s Neutrino 400 will be suitable for temperatures down to -7C (for the average man), whereas a Women’s Neutrino 400 will only be suitable down to -1C (for the average woman).

Mountain Equipment
When it comes to ME bags the main differences are:

Size and shape

• The women’s bags have a max user height of 5ft 7ins (170cm reg) or 6ft (185cm long). The men’s is 6ft (185cm reg) and 6ft 6ins (200cm long).
• The women’s bags have smaller footpieces. They are a few cm shorter (ie offer less room for feet) to take into account smaller average feet. The weight of down in the footbox is the same as the men’s so effectively this is a greater down density and so will ‘feel warmer’ assuming it is the correct size for your feet.
• In principle the Women’s bags all use the same Alpine fit shape as the Men’s, but design changes at ME mean that newer Men’s bags are slightly broader at shoulder, waist, hip than the old ones, and hence than the current Women’s alpine fit bags. These differences will be resolved over time.

EXL stitching
ME Women’s bags have EXL elasticated stitching at the waist to offer a more comforting fit and to reduce excessive dead space where air can begin to circulate.

ME infer the ratings of the Women’s bag from the Men’s but also quote their own ‘Good night’s sleep guaranteed rating’ which in the case of the Helium 400 bags is -3C for the Women’s bag and -5C for the Men’s.

Therefore they seem to be acknowledging that there’s a difference but its only slight.

Sierra Designs
Sierra Designs make some very innovative equipment and the Cloud 20 sleeping bags are no exception. The 20 in the title refers to the temperature performance and the male and female versions have been matched to this temperature using the EN testing ratings.

So, the EN tests reveal the Cloud 20 (20 degree Farenheit converts to -6.6 degrees Celsius) to be warm down to a temperature of -10C for men and -6C for women, and the women’s version has 40% more down in it, is shorter by 4 inches and is 150grams heavier.

Nemo
Nemo have taken the view that a Man or Women’s sleeping bag of the same model should keep the occupant warm in the same conditions – so they have quoted a -9C Comfort rating on the women’s bag and a -9C Comfort Limit rating on the men’s bag. In order to achieve this similarity of performance they have actually put 50% more down in the women’s bag than the mens, and the women’s version weighs significantly more even though it is 6 inches shorter.

*The ISO standard is an uprated version of the EN testing protocol introduced in 2017, the rating on the new standard should be the same as the old one, it’s the testing protocols that have been updated.

Marmot says
Women’s sleeping bags are ergonomically designed for women and have more insulation in key areas.

Big Agnes says
Our women’s specific bags differ in shape and fill weight with a less drastic taper from shoulders, to hips, to feet - reducing cold spots and creating more warmth where you need it.

Some manufacturers do not make Women’s specific sleeping bags
One of our biggest brands in sleeping bags is Thermarest who don’t make any women’s specific sleeping bags and there is an argument that if you make a particular bag in small, regular and long then there shouldn’t be a need for a women’s specific of a shorter length.

The shape of a bag also changes slightly from model to model, ultralight bags tend to be a closer fit whereas mid-range bags tend to be more roomy, so you could find what you are looking for among their range for a man or a woman. Certainly Thermarest see their bags as Unisex rather than designed for men.

• Western Mountaineering
• Lightwave
• Crux
• Criterion
• Montbell

So, should you buy a sleeping bag tailored to your gender?
Our advice is to consider all sleeping bags that are suitable for your intended use and choose the best model based on the amount of down in it and the quality of that down – then factor in the features that you value, be that a shoulder baffle, full length zip or more down in the footbox.

Pay particular attention to which EN rating is being quoted by the manufacturer, if you are a woman then technically speaking you should be considering the Comfort Rating, if you are a man then the Comfort Limit rating is the key one to consider.

Mark Richardson
Mark was the founder of Ultralight Outdoor Gear back in 2006 and has completed long distance backpacking routes in some of the remotest parts of the world. His favourite hikes have been Torres del Paine (full circuit), the John Muir trail and the Markha Valley trail (Ladakh, India). Although semi-retired Mark has not lost any enthusiasm for minimalist backpacking and is tackling Scotland’s Munros choosing multi-day backpacking routes over the more usual guide book excursions. Read more from Mark Richardson