While Oklahoma didn’t experience the Polar Vortex that affected much of the Midwest, we do get our fair share of winter weather. With that colder weather comes higher heating costs. Aside from keeping the thermostat set low and wearing a coat in the house, what can you do to lower your bills?
Gas and electric bills can reflect the efficiency, or inefficiency in some cases, of your home. Obviously, good insulation in the home is a must, but did you know a well-planned landscape also can help cut your heating bills in the winter, as well as your cooling bills in the summer?
Unprotected homes lose much more heat on cold windy days than on equally cold still days. Well-located trees and shrubs can intercept the wind and cut your heat loss. Up to one-third of the heat loss from a building may escape through the walls and roof by conduction. Wind increases the convective air currents along outside walls and the roof, thus increasing heat loss.
Air leakage accounts for as much as one-third of heating losses in some buildings. Cold outside air flows in through cracks around windows, doors and even through pores in the walls. Both windbreaks and foundation plantings can reduce this wind penetration. Research has shown windbreaks can reduce winter fuel consumption by 10 to 30 percent.
The amount of money saved by a windbreak around a home will vary depending on the climate, location of the home and how the house is built. A well-weatherized house with adequate ventilation, caulking and weather-stripping won’t benefit from windbreaks nearly as much as a poorly weatherized house.
In addition to reducing the force of the wind, windbreaks also can reduce the wind chill impact on people outside the house.
Studies of three-row windbreaks, where trees were 25 feet tall, show wind velocities and the wind chill index were effectively reduced by as much as 60 percent up to 125 feet downwind. It’s estimated a cedar type windbreak can reduce wind speed from 12 mph to 3 mph up to two times the height of the trees. Therefore, locate your windbreaks from two to five times the mature height of the windbreak trees from the house.
However, those of you living in urban areas likely don’t have that much space around your home. Fortunately, even a single row of evergreens is beneficial. Where space for the windbreak is at a minimum, try some of the slim juniper cultivars like Skyrocket. Vines on a wire fence, trellis or arbor can make a major contribution to wind and sun control in a limited space. Planting shrubs, bushes and vines next to your house creates dead spaces that insulate your home in both winter and summer. Plant so there will be at least one foot of space between full-grown plants and your home’s wall.
Windbreaks should extend beyond the area to be protected since wind speed increases at the ends of the windbreak. Where space permits, windbreaks of two to five rows of trees and shrubs extending 50 feet beyond the ends of the area should provide good protection. Trees should be spaced 6 feet apart in the row and the rows should be 10 to 12 feet apart with trees planted in a staggered arrangement. Evergreens provide the best protection, but dense branching deciduous trees can significantly reduce wind speed, too. Height and density are the most important factors when selecting plants to reduce wind.
In addition, windbreaks can be located to control snow. This reduces the energy required to remove snow from around homes, other buildings and roads. Make sure windbreaks are located so the desired effect on drifting snow is achieved.
If your heating bill this winter has taken a big bite out of your budget, evaluate your landscape to see if additions of trees and/or shrubs this year might help reduce the bill next year.
David Hillock is a consumer horticulturist with OSU cooperative extension.