What is a sleep system?
Your sleep system consists of the equipment used when sleeping out on the tracks. This will usually mean your Sleeping mat, Sleeping bag or Quilt and sleeping bag liner.
bear in mind most of these items are also very relevant in emergency/survival situations when dealing with exposure related problems.
How do we select the best sleep system?
The Best sleeping system will be one that meets the requirements of the style of camping you intend to do, for this write up we will focus on lightweight hiking style set ups, though the principles all apply to general camping equipment also.
The three main factors to consider when choosing the elements of your set up will be temperature (how cold will the ambient temperatures reach on your journey?) the weight of the set up as a whole and very importantly how comfortable the set up will be for you as the user (think length of sleeping bags and mat, thickness of sleeping mat, would you like a pillow etc)
Sleeping bags
It’s very important to know that in Australia we have no industry standard by which sleeping bags are uniformly measured and rated against for temperatures. This leads to massive amounts of confusion and many unwary adventurers have found themselves very underprepared and cold on chilly trail nights.
In saying that many of your more reputable brands will sell their product on other continents and it’s not uncommon to see the European EN13537 and the newer ISO 23537-1:2016 ratings advertised on higher quality sleeping bags. These ratings prove that the bags have been tested and allow you to compare like for like on multiple options when looking to purchase a new bag. An example of this is that if you have two different sleeping bags of similar dimensions that both advertise a tested rating of -5 comfort, both bags will ‘feel’ the same to a user, so the purchasing decision can be based on other factors such as pack down size, weight and cost.
In a moment we will go through what the ratings mean but first it’s important to note that the ratings are tested in such a way as to assume a few criteria are met by the user. These are:
- Wearing thermal base layers
- Sleeping on an insulated sleeping mat of R-value 3.2 or higher (more on this to come)
- Inside a tent
- Based on average male to be 1.73m tall and 73kg and average female to be 1.60m tall and 60kg both aged 25. The age part is relevant as our personal metabolism can have an affect on how ‘warm’ or ‘cold’ we sleep.
If your planned use will lack any of the above criteria then it’s important to know that your sleeping bag will not perform the same as advertised.
The temperature ratings on sleeping bags will usually be displayed as
- Comfort — the temperature at which a standard female can expect to sleep comfortably in a relaxed position.
- Lower Limit — the temperature at which a standard male can sleep for eight hours in a curled position without waking due to cold.
- Extreme — the lowest temperature at which a standard female can remain for six hours without risk of death from hypothermia (frostbite is still a possibility).
So when choosing your next bag look at the temperature rating relevant to you. If you’re a female or a cold sleeping male be looking at the comfort ratings. Average to warmer sleeping males can look at the lower limit ratings for choosing their options.
Sleeping bags will be made of all different types of outer and inner materials which will dictate the robustness and ‘feel’ of bag but they can be simplified by the two main types of internal insulation. Synthetic or down.
Synthetic bags are generally much cheaper than their down counterparts and have some advantages. Generally a few hundred dollars cheaper than their down counterparts, easier to wash and will maintain some loft and insulation when wet making them ideal for water based adventures such as canoeing, sailing and packrafting. These are also the choice for many users based on ethics as you will generally have no animal sourced products used in the construction of the bag.
Down bags will cost a lot more than their synthetic counterparts though come with some impressive advantages. Down is much more compressible than synthetic fibres and lighter weight when comparing insulation qualities, so a good quality down bag will pack down smaller and lighter for the same temperature rating as a synthetic option. Down itself if looked after by storing correctly and washing with special down wash is usually longer lasting than synthetic fibres so the bag will have a longer lifespan.
Further on Down fill there are a few things to look out for and consider.
- Fill power or commonly called ‘loft’ this will be shown as a number such as 650 loft or 850+ loft. The higher the lofting number the higher quality the down used is and the lighter it will be for its given warmth.
- How it was sourced. There is an unfortunate practice among cheaper equipment manufacturers where many will use down plucked from live birds, this is a process that is repeated many times and we would never recommend purchasing any down product that doesn’t display certification of responsible souring (usually as a by product of the meat industry)
- Treated or untreated down? Down fill once wet doesn’t loft or trap any air, meaning no insulation which is potentially dangerous in an emergency situation. Many high end down bags will have a hydrophobic treatment applied to better wick moisture and maintain warmth.
Next up is to look at the size and features of the bag. Most sleeping bags will have multiple size options and some even a women’s specific shape to help you get a bag that’s big enough to have room for comfort without carrying extra weight an bulk that you don’t need from a bag that’s too big. You will also want to look at how many and where the zippers are located, how well the hood of the bag will cover your head and face in extreme cold and if the bag has any other clever features to make for a more comfortable sleep.
Quilts
Quilts are fast becoming a popular alternative to the traditional sleeping bag. This is largely because of the increased internal room offered at similar pack down size and weight to equivalent sleeping bags.
If you are a side sleeper or feel too restricted inside most lightweight sleeping bags, then definitely have a look at a quality quilt as a possible solution.
Most lightweight quilts will have straps that run underneath your sleeping mat to hold the quilt close enough that insulation isn’t compromised by airflow into or out of the system, on warmer nights these straps can usually be loosened or undone completely to cool down if you overheat.
Worth noting there is no industry standard anywhere for how to measure the temperature rating of a quilt. Temperatures displayed on marketing material and the quilts themselves will be a ‘best guess’ rating based on some fill power calculations and comparing them to equivalent sleeping bags.
Sleeping mats.
In the hunt for the perfect sleeping mat there are 3 things to pay close attention to. The R value (insulation rating), weight/bulk of pack down size and comfort!
There is an industry recognised way that sleeping mats are tested for their R values ASTM F3340-18 is the most up to date standard and is used by most major hiking brands including Sea to Summit, Nemo, Therm-a-rest and more. Ratings will range from 0 through to 6, the R stands for resistance and is referring to the thermal resistance offered by the sleeping mat to prevent body heat loss to the ground beneath you. Your sleeping bag will offer little to no insulation under your body as our weight compresses the fibres of the bag and without that ‘loft’ heat is transferred through. This makes it particularly important that the sleeping mat you choose is insulated enough for your type of adventures. In tropical areas where the nights and the ground stay warm you may be able to use a non insulated mat and save on weight however temperate climates will generally demand R values of 3.0 or higher and trips getting into more alpine territory will want R values of 4.5 and higher, just remember the higher the R value, the warmer you will be.
Weight and Pack down size will be largely based on the size and style of mat. Self inflating and closed cell foam mats will normally be bulkier than manually inflated sleeping mats like the Nemo Tensor or Sea to Summit Ether Light XT but are normally robust and have less to go wrong than what can happen to a blow up option. Sleeping mats come in a range of sizing and shapes and this whilst contributing to pack down size and weight should be mostly considered as a comfort choice.
Comfort is a very individual choice here and we recommend heading into store and trying out a bunch of different options when making this decision but there’s a few things to think about. The size of the mat. Is it long enough for your height? Wide enough for you to move around on and thick enough that you won’t touch the ground through the mat? Think about what sleeping position you normally go to by default and be sure that your mat will be comfortable in that position. Comfort
isn’t just for our sense of touch though. Some sleeping mats can be very noisy and disturb light sleepers and other hikers who may be sharing your camp site. Have a roll around on the sleeping mat to see if it’s quiet enough for your needs.
Liners
Sleeping bag liners serve multiple purposes and are always worth having. Usually made from Cotton, Silk, a blend of the two or a synthetic thermal material. The main idea behind the liner is to keep your sleeping bag clean and protected from any oils or grime on your body. The less often you must wash your sleeping bag the better, from both a convenience and longevity point of reasoning.
They will assist in regulating temperatures. You can purchase insulated liners that can add realistically anywhere up to 10 degrees Celsius of extra warmth to your bag. This can mean only having to own 1 high quality bag and a couple of different liners to use depending on the season.
Some handy tips to get the most from your sleep system
- Sleeping bags will ‘loft up’ more, the longer they have been out of their compression bags, giving them a shake and getting them out well and truly before bed time will make for a much warmer night’s sleep
- Store your sleeping bag out of it’s compression bag, most important for down bags but still relevant for synthetic. Storing in a pillow case or dedicated storage bag will both increase the life of your bag and make for a quicker loft up.
- Down bags will sometimes ‘leak’ a few feathers, this is normal and not concerning.
- Sleeping mats will normally feel a little softer in the morning than they did the night before. This is normally due to col ground temperatures cooling the air inside the mat. Colder air takes up less volume than warm air so the mat feels softer. Our tip is to inflate the mat ever so slightly firmer than perfect as it will soon feel just right!
- Some sleeping mats inflate easier than others! None are fun to blow up by mouth so look at what options exist for fast inflation.
- Sleep systems don’t create warmth! If your body is cold when you go to bed you will have less warm blood circulating! Before retiring for the night do some star jumps, go for a jog or do anything that will get you warm (but try not to break a sweat). Once warm, heading to bed your sleeping mat and bag will then do their job to trap that warmth for the night.
- If you wake up cold, repeat tip 6!
- If you struggle with cold feet, wear a beanie. Our brain is one of the most important organs of the body and will always get the most blood flow. Our feet way down the other end will get limited blood flow if our head is cold. Chucking on a beanie will free up blood flow to the other extremities.
