Sleeping bags and Quilts, do you have the right temperature rated product?
One of the most important pieces of kit when camping is a Sleeping bag and more recently Quilts are proving popular, particularly with the wild camper and backpacker, but how can we ensure that we get the right temperature rating and what do we need to look out for to ensure we have a comfortable night's sleep. At Valley and Peak we stock both, but specialise in Quilts, particularly Synthetic Quilts and Over quilts, which we manufacture ourselves as a standard or made to measure product. We stock the range of Sierra Designs Zipper-less Sleeping bags, which are a hybrid in addition, more about that later.
The most popular choice. I'm not going to go through all the features, advantages, disadvantages, construction techniques etc etc as I could fill a whole book about this. However I'm going to give some thoughts on a few areas where I have had issues in the past, and I know just from looking at Twitter conversations, others have as well.
The European Standard - EN13537 which gives temperature ratings is quite a good way of comparing various sleeping bags, whether synthetic or down. (At present there is not a standard for Quilts).
Often people get confused about temperature ratings and what they mean and also how they compare between men and women. I've also seen manufacturers and suppliers present the data in different ways.
I'm going to choose just two of the ratings which I think are the most important. I will ignore the Upper Comfort level which is not always quoted and the Extreme limit as I believe that no-one should purchase a sleeping bag based on that rating as there is a danger of frostbite or hypothermia at the temperatures quoted.
The ratings below are based on a person lying on an adequate sleeping mat and wearing a thermal long sleeved top and leggings with long socks and a hat. In the test a heated manikin is used, so this may not compare exactly to how people will sleep at the temperatures given. The table below shows the two main limits shown on most products.
|Comfort||Lower limit of comfort range, to which a woman will be comfortable in a relaxed position|
|Lower Comfort Limit||Lower limit at which a man in a curled position can sleep without waking.|
What temperatures are you likely to encounter in the year ?
|Seasons in UK||Likely night temperature range|
|Summer||15 to 8C|
|Spring and early autumn||10 to 0C|
|Late autumn and winter||3 to -10C|
Of course if your live in Southern Europe, your temperatures will be warmer in the summer and in the Nordic countries, winter temperatures may drop below -30C in some areas, so choose wisely.
Now some people just sleep colder or hotter than others so think about moving up or down one temperature level. Generally women are more likely to sleep colder than men, I have read that they need a 5C warmer bag but I have also read 8C, so definitely look to upgrade the warmth rating, unless you know for sure you will sleep warm.
The photo below show two Sierra Designs bags we have in stock, one on the right suitable for spring and summer and on the left suitable for late autumn and winter where temperatures don't dip beyond the -7C mark if you are a man. I personally think that a good minimum guide at least for me is between the levels indicated, so for the Cloud 35, that would be around 0C, you may be different and perhaps want to stick to the comfort limit of 2C. For a woman, this bag may get you to say 7C in comfort if you are a cold sleeper, and perhaps going for the one on the left with more down in it would be more appropriate.
Everyone is different and this may need some trial and error, so I always think one should err on the side of caution if you are new to this. Of course you can always add additional insulated clothing in the night if you are feeling a bit cold.
Now quite established, but not as popular as sleeping bags, quilts with the comfort, freedom, weight and flexibility compared to a sleeping bag have won over many a backpacker. As stated earlier there is no EN Standard for Quilts, but maybe one will be developed in the future. Most manufacturers will provide approximate temperature ratings whether synthetic or down.
Here are our ratings for our synthetic Classic Quilt below using Climashield Apex insulation
|Climashield Apex Level||100||133||167||200|
|Temperature rating||10 to 8C||5C||2C||-1C|
In the pursuit of ever lower weight, many lightweight down sleeping bags and quilts use a simple 'stitched - through technique' where, the shell and liner are sewn together to create channels for the down (which stops migration). One of the problems is that this can cause a series of cold spots across the sleeping bag or Quilt. This was one of the reasons why we were attracted to manufacturing synthetic Quilts and Over-Quilts made out of Climashield Apex insulation as you can make them from using one continuous sheet of insulation, with the fabric and insulation sewn together around the complete perimeter of the Quilt with no cold spots.
As you can see from the table above, most Synthetic Quilts typically will go down to -1C, however you can go lower by adding additional sheets of insulation sandwiched in between the outer and inner fabrics. Down quilts can go as low as sleeping bags but once you are significantly below zero, they are generally not likely to be as thermally efficient as a mummy style bag. The use of a strapping system, which straps the quilt to a sleeping mat and cuts out draughts together with placing the synthetic or down quilt in a Bivy bag or inside an Over-Quilt will also help to remain comfortable in lower temperatures. Our unscientific tests suggest an additional 5C added by placing a Quilt in our Ultra Bivy.
This is becoming an increasing popular way of increasing the warmth of any sleeping bag or quilt. By adding a lightweight synthetic Quilt to a sleeping bag you protect the down sleeping bag or Quilt from damp conditions which can cause poor lofting of the down, and at the same time increase the temperature rating. It will also allow you to take a summer sleeping bag in combination so that you won’t generally need a 'full on' winter bag.
Just make sure the Quilt you are using is wide enough to allow adequate loft of the down sleeping bag or quilt, many probably won't be. Better still get a made to measure Over-Quilt from us to make sure of this. In the photo above, the Over- Quilt was made especially to add warmth to another and was made big enough to incorporate a sleeping mat inside as well.
Zipper-less sleeping bags
Sierra Designs have developed a range of Zipper-less bags ideal for people who would like the idea of a quilt but don't want to leave the familiarity of a mummy bag. On the face of it, they look like a normal mummy bag but where one or both sides opens up so that you can tuck around you to keep snug. If you are too warm this top section can be laid out on top of you like a quilt. These have been tested under EN 13537 and have a temperature rating like standard sleeping bags. The Zipper-less sleeping bags are ideal where you encounter a wide range of temperatures, because of the venting options.
We cannot rely solely on a sleeping bag or quilt to keep us warm. Remember that a sleeping mat needs to be adequate to reflect the season(s) that you will be camping, so a summer mat in winter will not keep you warm even if you have a good winter bag, simply because you will feel the cold underneath. The EN tests above were tested using a manikin, with a long sleeved top and long bottoms with socks and a hat, so dress similar if you want to feel comfortable in your bag or quilt.
Doing some light exercise prior to getting into the bag or quilt and eating some food will help stoke 'your inner furnace'. Remember don't go to bed cold, it will take a lot longer to get warm.