Ever wondered how you could reduce your energy bill over the winter months? Ron Beattie from Beattie Passive looks at how a Passivhaus might have the answer.

Christmas is approaching, the nights are drawing in and the weather is getting colder. This can often be an expensive time of year as the house gets colder and the heating needs to come on more and more to compensate. The good news is, there is a way to greatly reduce your heating needs (and hence, energy bills) in the winter months, called Passivhaus.

Passivhaus is often considered the Gold Standard of comfortable, energy efficient living. This is because nearly all aspects of a Passivhaus build are designed to maximise heat retention. ? High-quality thermal insulation: Continuous 'super insulation' ensures that the home is well-insulated from the floor, to the walls and the roof. Cold bridges (areas of high thermal conductivity allowing heat transfer to the outside) are completely eliminated, keeping the heat locked in and the cold air from outside out.

? Airtightness: Airtightness is an essential part of Passivhaus builds. The Passivhaus requirement for airtightness is incredibly stringent, at no more than 0.6 air changes per hour. A high airtightness value further reduces heat loss as cold air cannot leak into your home from the outside, and the warm air does not escape as quickly, therefore you are not continually reheating the air in your home.

? Windows and doors: Homes can lose up to 10% of their heat through conventional windows. Passivhaus certified windows are triple-glazed, with Argon gas between the panes to prevent heat loss via radiation through the glazing. They have an airtight seal around them to stop air leakage around the frame. Finally, they are carefully designed to ensure that all thermal bridges are eliminated, removing the risk of losing heat through cold bridges.

? Mechanical Ventilation and Heat Recovery unit (MVHR): The lynchpin of every Passivhaus build, this is what makes Passivhaus work. Given that the airtightness of a Passive property is so good, the MVHR unit is necessary to provide a constant stream of fresh air into the property, while removing the stale air from the house at the same time. The Heat Recovery part transfers most of the warmth of the outgoing air into the incoming fresh air, keeping the house at a constant comfortable temperature throughout, come rain or shine (or snow)!

In these ways, Passivhaus proves to be the best, eco-friendly way to keep your home comfortable and warm throughout the winter months, even without the necessity of a traditional central heating system (although at least one radiator recommended for especially cold weather!). Some of our Passivhaus clients are even donating their winter fuel payments to charity, as their heating bills are so low!

This column is sponsored by Beattie Passive.