see also:

• keeping warm when camping or hiking
• air beds, mattresses and stretchers for camping
• photography and camping main index page

• sleeping bag liner sheets are essentially thin fabric bags in which you get into as either a summer “sleeping bag”, a wind chill protector for sleeping under blankets, or as a protector and additional warmth factor when sleeping in sleeping bags (skin oils will eventually adversely impact down sleeping bags and a liner significantly reduces this)
• some have zips down the side and some also have a foot zip for those with hot feet
• some have a section to hold pillows

• polyester
  • this is usually the cheapest and easiest to wash and dry
  • can usually buy a double for ~$30
• “silk-like” synthetics
• cotton
  • preferred by many but perhaps not the best for hiking - cotton can take a long time to dry out if it gets wet
• merino wool
  • an uncommon option but can provide extra warmth
• “thermal liners”
  • usually made from a variety of synthetic fabrics to provide additional insulation
  • eg. Sea2Summit “Thermolite” Reactor - stretch knit fabrics
    • https://seatosummit.com.au/products/reactor-lightweight-liner said to add up to 4°C|7°F
    • https://seatosummit.com.au/products/reactor-midweight-liner said to add up to 6°C|11°F
• silk blends
  • eg. https://seatosummit.com.au/products/silk-blend-sleeping-bag-liner
• silk
  • the most expensive, lightest and most compact of the liners - great for hiking, and for summer use alone
  • adds 1-2°C warmth
  • primarily use silk liners for hygiene (keeping sweat, dirt, and body oils out of expensive down sleeping bags so you don't have to wash them as often) and a smooth, comfortable feel against the skin rather than heavy-duty winter warmth although it can help with wind chill when used alone on warmer nights
  • eg Mont pure silk inner sheets $229 for a double
  • eg. Sea2Summit ~$290 for a double https://www.amazon.com.au/Sea-Summit-Premium-Sleeping-Liner/dp/B00EI730AI/
  • eg. Vietnamese hand made: https://www.etsy.com/au/listing/772266184/double-100-mulberry-silk-sleeping-bag ~$130 for a double

• this allows you to have more bulky cheaper options
• I prefer to sleep naked in a 2P hiking tent on an insulated self-inflated air bed with a sheet for many reasons, in particular, it helps to keep the air temperature warmer as your body is a 100W heater
• thus as the temperature drops I just add layers:
  • above 20-22degC without wind chill, can just sleep naked, perhaps with a summer sheet only or silk liner (especially if there is some wind chill or temperature is dropping)
  • below this I add a polyester “blanket” (don't usually use a summer sheet or silk liner with this as it means more things to keep in place)
  • as temperature drops below 16degC, I add a woollen fire blanket (I keep this as it has many uses including bush fire protection)
  • if temperature drops below 14degC, I use a polyester sleeping bag liner (or a thermal fabric liner) and may add loose socks and a thin balaclava +/- thin skivvy
  • if temperature drops below 10degC, then I generally resort to adding a sleeping bag and definitely have a thin balaclava
  • if I am still feeling cold then I would add thermal leggings as well as a skivvy and loose dry socks
  • alternatively, I might turn on a 12V electric blanket or use a wood stove for the coldest part of the night to ensure air temperatures are maintained above 5-10degC