A good sleeping bag is halfway to a good night’s sleep – essential for a safe day’s paddling. However most expensive is not necessarily best…
The modern sleeping bag packs down to a small, lightweight package easily stowed in the hatch of a sea kayak. I always choose a 3-season bag as this can be supplemented with a couple of mummy liners for colder temperatures and the same bag can be half unzipped during summer months.
Synthetic sleeping bags
Synthetic bags will insulate even when wet and the material dries more quickly and more easily than down equivalents. However they are bulkier, heavier and do not last as long. There are many types of synthetic bag fillings but a good one, such as Spirafil, is highly technical so as to achieve a balance of insulation with pack down size. Cheaper fillings are bulky and do not insulate as well.
Down sleeping bags
Feather down sleeping bags are more expensive and require more looking after but are lighter and will compress to smaller sizes. When choosing such a sleeping bag, choose one with a high percentage of all that matters such as 95% down and 5% feather. A sleeping bag with a lower percentage will not be as warm. The best way to store a down bag is to hang it so the entire item is free of any compressed areas –those that become permanently flattened down are called dead spots and will fail to insulate.
So long as a down sleeping bag is carried in a dry bag, kept out of contact of water, deployed on a ground sheet on a slightly elevated camping area – in my opinion, down is best. Especially so for those in kayaks with small storage hatches. If it makes you happier just use two dry bags.
Sleeping bags, whatever quality, are compressed under body weight and lose much of their ability to insulate underneath their user and this can be most noticeable when sleeping in a hammock.
It is important therefore always to have a good insulating matt, either foam or inflatable, on which to sleep. Otherwise you may be in for a long night.