How well insulated is your home? You might think it's pretty toasty, but with as many as 25 million UK properties not expected to meet government standards by mid-century, it might not be as well-insulated as you think. Making sure your loft and cavity walls are well insulated is a big step to a warmer, more energy-efficient home, and could help save money on your energy bills too. How? Well, most heat is lost through your roof and walls, so without proper insulation, it's escaping as soon as you turn the heating on.