Most of us will have bought duvets (and matching pillows) in our lifetimes. Yes, we do take care looking at the fibre content, quality and ‘washability’ of the duvets and pillows. But how many of us have seen the tog rating and known what it actually means for us individually?
A tog rating refers to the thermal density of a duvet or other fabric and what’s in the duvet can dramatically affect the tog rating. Different fibres have different levels of warmth when it comes to sandwiching warm air between their layers. Natural fibres like cotton, down and wool tend to be much more effective at trapping warm air. These materials need much less than a synthetic counterpart to trap the same amount of heat, meaning that natural material duvets can appear much lighter. However, they will have the same tog rating as a heavier synthetic duvet. An increasing amount of people have allergies to natural fibres, so often synthetic-filled duvets are a better choice for them. The tog system of measurement was developed in order to demonstrate how warm and comfortable fabrics were – also known as their thermal resistance. This thermal resistance is calculated using a specific scientific formula that works out the fabric’s ability to trap warmth over certain areas. However, using the scientific measurement of m2K/W is a bit of a mouthful, so it was given the nickname ‘tog’, after the informal word for clothing. This testing was established in the 1940s by the Shirley Institute in Manchester, which had come up with the measurement’s nickname and the tog scale – the Shirley Togmeter!
With different duvets having different tog ratings, it’s essential to pick one that is correct for the season. Most British duvets start at 3.0 tog, which is suitable for a very lightweight summer covering and then moves up to the heavier winter weight of 13.5 tog, as well as everything in between! Having the right duvet for the season will help keep you just warm enough without being stuffy or uncomfortable. Of course, personal preference varies, and you might have to try a couple of different tog duvets before you find the perfect one. You can also get an All Seasons Duvet where two separate tog duvets in a high and low tog pop together to form a cosy, heavy winter-weight duvet – great value and perfect for variable British climates…and also easy to store!
