Tog Ratings & Warmth Guides For Sleeping Bags
Many sleeping bags use the European TOG rating system to indicate how warm the sleeping bag is and what season they are suitable for. The higher the TOG, the warmer the sleeping bag.
The Tog rating describes the warmth or "Thermal Resistance" of a product and is widely used to explain warmth levels of duvets. Unlike duvets infant sleeping bags have lower tog rating numbers. It is rare to find a safe sleeping bag that is rated over 3.5 tog. For our climate and heated homes 2.5 tog is usually high enough although we have tog rated options up to 3.5 tog in some brands. Alternatively a Duvet Woolbabe (which isn't tog rated because it is made with Merino) is one of our warmest sleeping bags.
A number of external factors determine the tog rating of the sleeping bag that should be used. These include the quantity of clothing the baby is wearing, the temperature of the infant’s bedroom, the baby’s health and the amount of bedding necessary to keep an individual infant warm – this may vary as it does for adults. Check your baby regularly to ensure they do not overheat.
Many sleeping bags that we stock come with a free nursery thermometer to help you select which tog baby sleeping bag to use and what sleepwear to put your baby in.
The TOG indicates approximately how many blankets the sleeping bag is equivalent to. Bags with rating of 0.5 and 1 or below are for spring/summer use. Bags with rating 2-2.5 are for autumn/winter.
Why are some sleeping bags tog rated and others are not?
Sleeping bags with polyester or man-made fibre fillings that can consistently perform to a testing standard or set temperature range tend to be tog rated. In general sleeping bags made with Merino are not tog rated, as they are a natural fibre which adjusts according to temperature, this is one of the reasons natural fibre Merino sleeping bags are so popular. Merino is also amazing at wicking moisture away from the skin. Woolbabe bags have the widest temperature range - the 3-seasons bag can be used for rooms 18-28 degrees, and the duvet weight bag can be used at 14 to 22 degrees.
To read more about which Woolbabe to choose for the room temperature and the clothing guide click here.
Is there a sleeping bag that can be used all year round in any temperature?
The short answer is no, not really. As the seasons change you'll need to adapt your baby's clothing and sleeping bag combinations to keep them comfortable to their room temperature. Most families find that they need at least two weights or togs of sleeping bag so that their baby doesn't overheat or become too cold at different times of the year. Scroll down to the table below to find a dressing guide for our most popular styles.