Two duvets with different duvet tog rating with a thick duvet and a light duvet.

Which tog should I choose for my THREE Duvets section?


Choosing the right duvet fillings and tog rating

Just because one of you wants a cooler duvet and the other prefers something warmer, there’s no need for one of you to compromise any longer! With THREE Duvets, you each choose your own half section, and both sections join seamlessly together to create one duvet to fit inside your usual duvet cover. There’s a choice of two duvet fillings and togs and we’ve explained how they work below.

Diagram comparing winter and summer tog duvet with different tog ratingsDiagram comparing winter and summer tog duvet with different tog ratings

What are tog ratings?

A tog rating is a measure of thermal insulation. Originally created for the clothing market, all duvets now also come with their own scale of warmth level called a ‘tog rating’. This specified warmth, not thickness. With duvets, the higher the tog rating, the warmer the duvet. Conversely, the lower the duvet tog ratings, the cooler the duvet. Many duvets, including synthetic, feather/feather & down/down have a fixed tog rating, which reflects their insulation factor but also means they are generally not able to temperature regulate, i.e., unable to release heat if you need to cool down. Most synthetic fibres will trap heat when you are hot and make you feel even hotter!

The fillings in all natural duvets in our individually handcrafted THREE Duvets sections are able to temperature regulate, so the tog rating is not fixed. They are also natural, sustainable and chemical free, which makes them better for you and for the environment. The casings for our THREE Duvets sections are made from 100% cotton, certified by Better Cotton.


Seamstress sewing separate duvets for couples with duvet constructionSeamstress sewing separate duvets for couples with duvet construction
Synthetic duvets vs a natural duvet laying on a bed to show the different togsSynthetic duvets vs a natural duvet laying on a bed to show the different togs

Wool duvet filling: certified fully traceable, 100% British wool

Features: Breathable, moisture wicking, dust mite resistant

Benefits: Temperature regulating, hypoallergenic. It works with you and the ambient temperature in your bedroom and so has a fluctuating tog equivalency. We have three options for you or your partner to choose from.


Lightweight (4 – 7 tog equivalency):

Contains 1 layer of wool (300g per square metre). Can act in a similar way to a 7-tog duvet if you need some warmth but can also release heat down to a 4-tog duvet if you need to be a bit cooler. It won’t go above 7 togs or below 4.5 tog togs. Suitable for: The warmer months, or all year if you live in a well-insulated property, or if one of you is a naturally ‘hot’ sleeper, including if you are currently experiencing hot flushes or night sweats.


Medium Weight (8 – 14 tog equivalency):

Contains 2 layers of wool (600g per square metre). Can provide warmth up to a 14-tog duvet when you need to snuggle up, but can also release heat down the duvet togs to the equivalent of a 8-tog duvet if required. It won’t go above 14 togs or below 8 togs. Suitable for: The cooler months (including Winter), or all year if you or your partner are naturally ‘cold’ sleepers or feel the cold more because one of you likes a cool bedroom.


Extra Warm Winter Weight (14+ tog equivalency):

A very substantial duvet with 3 layers of wool (900g per square metre) that is very warm and offers a tog equivalency of 14 togs and up to around 18 togs. 

Suitable for: Winter - and particularly if your or your partner really feels the cold. This is a popular weight for those who live in colder parts of the UK or for those who want to turn down the dial on the thermostat in the bedroom and save on energy bills.

Browse our British Wool section here.


Silk duvets vs a synthetic duvet to show the natural properties on THREE duvetsSilk duvets vs a synthetic duvet to show the natural properties on THREE duvets

Alpaca duvet filling: certified fully traceable 100% British alpaca wool

Features: Finer fibres, breathable, moisture wicking, dust mite resistant.

Benefits: Temperature regulating, hypoallergenic, slightly lighter than a wool duvet section. It works with you and the ambient temperature in your bedroom and so has a fluctuating tog equivalency. We have two options for you or your partner to choose from.


Lightweight (3 – 6 tog equivalency): 

Contains 1 layer of alpaca wool (200g per square metre). Can act like a 6-tog duvet if you need some warmth but can also release heat down to the equivalent to a 3-tog duvet if you need to be a bit cooler. It won’t go above 6 togs or below 3 togs.

Suitable for: The warmer months, particularly if one of you is a naturally ‘hot’ sleeper. Might not provide quite enough togs in the cooler months unless your bedroom is very well insulated and keeps a consistent temperature throughout the night.


Medium Weight (7 – 10 tog equivalency): 

Contains 2 layers of wool (400g per square metre). Can provide warmth in a similar way to a 10-tog duvet but can also release heat down to the equivalent of a 7-tog duvet if required. It won’t go above 10 togs or below 7 togs.

Suitable for: Those who need a bit of extra warmth even in the warmest months of the year, or for the cooler months (including Winter) in a well-insulated property.

*Alpaca is a Limited Edition filling as we only ever use British alpaca wool and there are a lot less alpacas than sheep in the UK. So, once it’s gone, it’s gone…until next year’s shearing!


Browse our Alpaca section here.

Summer duvet with a duvet tog rating for those warm summer nightsSummer duvet with a duvet tog rating for those warm summer nights

Best duvet for dust mites and hypoallergenic made with 100% british woolBest duvet for dust mites and hypoallergenic made with 100% british wool

Botanic duvet filling: 100% plant-based (TENCEL Lyocell)

Features: Breathable, moisture wicking, dust mite resistant, vegan friendly wool alternative.

Benefits: Temperature regulating, hypoallergenic. It works with you and the ambient temperature in your bedroom and so has a fluctuating tog equivalency, although not as wide ranging as wool or alpaca. We have three options for you or your partner to choose from.


Ultralight (2 – 4 tog equivalency): 

Contains one layer of plant-based fibre (200gsm). Can act like a 4-tog duvet if a little extra warmth is required and a 2-tog duvet if less warmth is required. Suitable for: Summer, but also in Spring or Autumn if one of you is experiencing night sweats.


Lightweight (4 – 6 tog equivalency): 

Contains 2 layers of plant-based fibre (400g per square metre). Will act like a 6-tog duvet if you need some warmth but can also release heat down to a 4-tog duvet if you need to be a bit cooler. It won’t go above 6 togs or below 3togs. 

Suitable for: The warmer months, particularly if one of you is a naturally ‘hot’ sleeper. Might not provide quite enough togs in the coolest months. but, again, might be suitable throughout the year if one of you is a naturally ‘hot sleeper’ or experiencing night sweats.


Medium Weight (6 – 8 tog equivalency): 

Contains 3 layers of plant-based fibre (600g per square metre). Can provide warmth up to the equivalent of an 8-tog duvet but can also release heat down to a 6-tog duvet if required. It won’t go above 8 togs or below 6 togs. 

Suitable for: Summer in a slightly cooler property, Spring and Autumn in a more well-insulated property), or if one of you is a ‘hot sleeper’ in the coolest Winter months.

Browse our Botanic Section here.


highest tog duvet 10.5 tog for those cold winter nights made of woolhighest tog duvet 10.5 tog for those cold winter nights made of wool

All of the sections in our THREE Duvets range are individually handcrafted by our expert seamstresses, here in our Devon workshops. If you have any questions on the best options for you and your partner, do get in touch with the team.


Winter duvet 13.5 tog rating with natural fillings for colder winter nights lifestyle bedWinter duvet 13.5 tog rating with natural fillings for colder winter nights lifestyle bed