Why site optimization is essential to energy-efficient building design

March 18, 2016

"Location, location, location." One of the most frequent refrains in the real estate world is equally important to designers planning sustainable buildings from the ground up. As building designers set their sights on achieving near net-zero energy usage, even the smallest decisions become increasingly important. From the amount of light that streams in each window to the amount of water it takes to maintain the landscaping, many of these details are tied to the land itself.

This is why no building, no matter how technologically advanced, can achieve its energy-saving potential without taking into account the features of its property. Here are a few considerations building designers must make if they hope to create the most energy-efficient building on a given site:

"Natural ventilation can save 10 percent to 30 percent energy consumption."

Is natural ventilation an option?
Buildings that are ventilated naturally can save as much 10 percent to 30 percent energy compared to those ventilated mechanically, according to the National Institute of Building Sciences. By leveraging naturally-occurring wind and buoyancy, rather than mechanical fans, to bring fresh air into buildings, designers can provide an acceptable indoor air quality and maintain a comfortable and productive climate without expending any energy.

Here's how designers can maximize natural ventilation by adjusting a building's relationship with its property:

  • Position the ridge of the building perpendicular to the direction of the summer winds.
  • Ensure summer winds can move into the building unobstructed.
  • Use a natural windbreak (such as evergreen trees) to block cold winter winds.
  • Determine whether the local climate calls for open- or closed-building ventilation. Buildings in hot, dry climates should be opened at night to let cooler air in, then left closed during the day, while buildings in warm, humid climates benefit most from a cross-breeze during daytime hours.

How much daylight can the building use?
By controlling the amount of sunlight that enters a building, designers can reduce electric lighting and save up to one-third of overall energy costs, according to NIBS. To achieve these savings, the most effective daylighting systems not only capture sunlight, but use a responsive control system to reduce electric lighting power when natural light alone is adequate.

Well-placed windows can lessen the need for electric lighting. Well-placed windows can lessen the need for electric lighting.

To make sure the planned system will perform well once it is built, the designer must be in tune with the particular light environment on the particular site – no one plan will serve two properties the same way. For example, the style and location of each lighting aperture will depend on the direction and type of sunlight typically available at each site. Windows are appropriate where direct sunlight tends to beam in, while more diffused light is best captured by ceiling skylights. Plus, the direction of the light can have an impact on the amount of glare in each room, which could lead designers to add glare controls, such as blinds or shades, or to fill the room with non-glare surfaces. 

Whether optimizing a building for natural ventilation, daylighting, or any number of other sustainable energy strategies, it is crucial that building designers understand how the site's environment can be either a lift or an obstacle. To learn how Benningfield Group can help you optimize your building plans for their specific sites, contact us today.