TOG Ratings Explained
Tog is the UK's standard unit for rating the warmth of duvets, sleeping bags, down jackets etc. The word is originally derived from the Shirley Togmeter, a piece of apparatus used to measure the thermal resistance of textiles.
Essentially, a Tog rating refers to how good a duvet or item of clothing is at keeping you warm.
A popular misconception is that Tog relates to the physical depth or thickness of a duvet, which is not the case. Different duvet fillings have differing degrees of thermal resistance, meaning a thick duvet with one particular filling could have the same tog rating as a thinner duvet with a more thermal resistant filling.
In the UK, duvets will usually range from 3 togs to 15 togs and are generally classified as follows:
- Summer duvets – 3 – 4.5 Togs
- Spring/Autumn duvets – 7 – 10.5 Togs
- Winter duvets – 12 – 15 togs