Trees save energy
As the cost of fossil fuels continues to rise, concerns turn not only to how to replace these resources, and how to buy time by minimising the amount we use now. According to our research, the average UK home could save up to a tenth of its annual heating and cooling expenditure with the natural winter insulation and summer shade provided by trees.
How does that work?In the winter months, houses inevitably lose heat to their surroundings, and in exposed areas, this heat is whipped away by fast-moving winds, drastically reducing the efficiency of the house’s insulation. The problem is most acutely felt in buildings which have no windbreaks outside, in mainly rural locations. And in towns and cities, streets act as wind tunnels, channelling cold wind as it takes with it the warmth from the houses it passes.
In America, the trend for natural windbreaks has already caught on. Evergreens are planted on the north side of a house, far enough away that they don’t obstruct views and their roots are not hazardous to the foundations, but close enough, and tall enough, that they divert cold wind over or around the house.
Evergreen trees are well suited to this task: they can grow together easily, and their branches grow even from the base of their trunks, both features boosting their ability to block wind.
Conversely, for the summer months, deciduous trees can be planted to provide shade on the southern aspect of a building, cooling it additionally by evapotranspiration, the removal of water from the surrounding air. And because these trees are deciduous, their leaves fall in autumn, allowing sunshine to warm the house during the winter months.