In general, room temperature inside a UK house should be suitable for mice. However, care should be taken that the temperature does not drop too cold over winter and it is best to aim for an ambient temperature of around 20-24C. Keep in mind that they will need plenty of nesting material to help with their body temperature regulation. This is due to the thermoneutral zone (TNZ) of mice, the temperature range in which their normal metabolic activities are enough to keep them warm. The TNZ of mice is higher than room temperature, around 30C, and bedding material helps them to keep their nest closer to these temperatures. Keep in mind that if the room becomes too hot, there nest will be even hotter – so temperatures of over 30C can cause significant heat stress to your pets. Speak to your local pet retailer for advice on keeping your small pets cool on hot summer days.