Energy Efficient Landscaping Tips

Deciduous trees on the south and west sides of your home can deflect hot summer sun. Photo Source: Alan Davey

By Pat Keegan and Brad Thiessen

The decisions you make about your home’s landscaping can help you stay cooler in the summer and warmer in the winter. With summer just around the corner, take a look at how strategic planting can help cool your home.

Direct sunlight hitting windows is a major contributor to overheating your home during summer months. By planting trees that block sunlight, you can improve comfort and reduce your air conditioning energy use. If the trees eventually grow tall enough to shield your roof, that’s even better.

The most important windows to shade are the ones facing west, followed by windows that face east. Morning and evening sunlight hits the home more directly than mid-day sunlight. Also, an eave on the south side of your home can help shade your windows during mid-day sun.

Deciduous trees can help keep your home cool during the summer by blocking the sun and warm it in the winter by allowing sunlight in. Photo credit: Marcela Gara, Energy Efficiency Database.

If you live in one of Colorado’s cooler areas, planting deciduous trees that lose their leaves in fall will shield your windows in summer and allow sunlight in during winter to help warm your home. A simple approach that can deliver some shade the first year is to plant a “living wall” of vines grown on a trellis next to your home.

One cooling strategy is to make sure your air conditioning compressor has some plants near it, but not too close. The compressor should have a 5-foot space above it and a 2- to 3-foot gap all the way around so that it gets enough air movement to do its job.

There are two other factors to consider that are important in some areas of Colorado:
1. Water is becoming more precious and more expensive. When you pay your water bill, much of that cost is for the energy required to pump water to your home, or perhaps you have your own well. Either way, reducing water use saves you money and reduces energy use.
2. If you live in an area that has wildfires, you should definitely take that into consideration as you develop a landscaping plan. What and where you plant on your property can either increase or decrease the risk of fire reaching your home.

If you live in a colder climate, a solid wind break can cut harsh winter winds. The best solution for this is a solid row of trees (preferably evergreen) on the windward side of the home, with shrubs underneath the trees to keep the wind from sneaking through. If you live in a warmer climate, you would not want a wind barrier as wind flow will help cool your home.

A row of low landscaping along the house can create a dead air space that provides an extra layer of insulation. Photo Source: Lynn Gallagher

Planting a row of shrubs a foot from the home can provide more efficiency in cooler climates. By stopping air movement, it can form a dead air space around the home that acts as “bonus” insulation. While you’re at it, add some foundation insulation if you have a home with a basement or if it’s built on a slab.

These are just a few ideas to help you get started. Also remember that, as with any landscaping projects that require digging, it’s important to call 811 to ensure all underground utility lines are properly marked and flagged before you start the work. Happy planting!

This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency.