Sleep systems

Sam Cook on Layering

Sam says:

"I have a long held belief in the 'layering principle' extending into our sleeping quarters and this is where PHD have developed a modern approach with their sleeping bag systems and 'layering the bags' to suit a multitude of adventure activity situations. To name a few: Expedition sea kayaking; Himalayan style trekking where you travel through a wide range of temperature zones; Cycle touring where there is a similar packing issue to sea kayaking and potential for travelling through temperature zones; plus, any adventure activist who needs to use their sleeping bag across seasons. Eg. Just 'layer up' to convert your summer bag into a 'winter warmer'. I have used my PHD bags in all the above situations."

Technical Note: Sam has a lifetime of experience across several adventure activities, as instructor as well as participant. He has been using our 'layered' bags for years and is fully convinced that nothing else works so well.  

PHD Sleeping Bags: 'the answer to all my dreams' by Sam Cook

Way back in 1976 me and my 3 mates were planning a sea kayak expedition to the arctic region of Spitzbergen in the Svalbard Archipelago …

Sea Kayaking was becoming a very popular sport but back in the early 70s kayaks with specialist compartments made by introducing bulkheads and access hatches were only just being developed.

We had a few problems with choosing what sleeping bags to carry …

•    There were no commercial 'dry bags' on the market.
•    There was potential for the bulkhead/kit areas to leak, particularly if damaged.
•    The access hatches were only 7 inches in diameter (now at least 10 inches), making difficult packing with bulky items like sleeping bags.
•    The temperatures we were likely to encounter could vary from +5 to -10 (even in July the sea surface could freeze – and did!!).
The 'dry bags' were not a problem. We could make our own. But the sleeping bags sure were. We needed at least 3 seasons warmth and what about if they got wet!!!!

I met up with the 'grand old father' of PHD, Pete Hutchinson. Luckily he lived only 8 miles up the valley and we already knew each other.

Between us we came up with some ‘bright ideas’.

•    carry two sleeping bags, which together would give us the warmth factor and used separately would allow for warmer temperatures.
•    Two less bulky items would be easier to pack and stow, and in separate compartments would reduce the possibility of both getting wet at the same time.
•    The chosen materials were synthetic filling (Hollofill was a recent innovation) and fibre pile, which at this time was quite 'hefty'. These were chosen to further alleviate problems with wet sleeping bags. Even then Pete knew that down lost most of its insulation when wet.
•    Our 'dry kit' also included a fibre pile 'all in one suit' which could be used for sleeping.

BINGO!!!!!!! And it worked. 

Jumping forward into the 21st century, a gap of over 40 years, and PHD are still 'ahead of the game' with innovative ideas and the best quality materials on the market.

I have a long held belief in the 'layering principle' extending into our sleeping quarters and this is where PHD have developed a modern approach with their sleeping bag systems and ‘layering the bags’ to suit a multitude of adventure activity situations.
To name a few:

•    Obviously expedition sea kayaking.
•    Himalayan style trekking where you travel through a wide range of temperature zones.
•    Cycle touring where there is a similar packing issue to sea kayaking and potential for travelling through temperature zones.
•    Plus, any adventure activist who needs to use their sleeping bag across seasons. Eg. Just 'layer up' to convert your summer bag into a 'winter warmer'.

I have used my PHD bags in all the above situations.

During August of both 2013 and 2014 I have been on sea kayak expeditions in Greenland where the bags have been tested in temperature ranging from just above freezing to as low as -10. It is a pleasure when you know the temperature is dropping just to slip into another bag and double the warmth factor. This has been achieved mostly with an 'overbag' and 'minimus' bags but the addition of the down sleeping bag liner has given even greater flexibility to the range of possibilities.

On 27 December 2014 I 'bivvied' in the snow on the fell above my house. Inside a bivvy bag and insulating mat I was as ‘snug as a bug’ in the overbag and down liner. So much so that I slept until 8am. The temperature dropped to about -6.

I should add that I normally camp out wearing 150 Merino wool top and bottom with a 'Buff' on the head.

If you have managed to read to here, and are interested in what I have said, get in touch with PHD and give it a try.

Thanks to PHD for all your help and warm nights. 

Sam Cook

Sam Cook on Layering
Sleep system mentioned in this case study
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