Energy-efficient building design is crucial for reducing environmental impact and long-term operational costs. When it comes to energy efficiency, some aspects of building design tend to get more of a spotlight—aspects such as lighting and HVAC systems. But there are neglected aspects of building design that are equally worthy of focus and can make a considerable difference in your building’s energy efficiency.
What Makes a Building Energy-Efficient?
An energy-efficient building is one that is designed, constructed, and improved to minimize energy consumption while maintaining occupant comfort and functionality.
According to the U.S. Department of Energy, buildings (both residential and commercial) are responsible for nearly three-quarters of the nation’s electricity use and over a third of its total carbon emissions. Overall, buildings account for 40 percent of the nation’s total energy consumption.
It’s no wonder environmentally conscious companies are looking for ways to do their part to cut back on this figure. In addition to environmental benefits, enhancing a building’s energy efficiency can improve a company’s public image, qualify it for tax credits, and lower utility costs.
According to the U.S. Energy Information Administration (EIA), the biggest source of energy consumption in commercial buildings is space heating (32 percent), followed by ventilation (11 percent) and lighting (10 percent). Just as there are many factors that can contribute to energy usage, there are likewise a variety of ways you can make a building more energy efficient. Anything that minimizes the use of utilities is a major win.
Overlooked Design Features to Include in Your Energy-Efficient Building Planning
Let’s look at a few of the less obvious ways you can design a building for optimized energy efficiency. You may be surprised how much of an impact these areas can have.
1. Passive Solar Design
Passive solar design lessens the burden on your HVAC system by leveraging sun exposure to maximize natural heat in cold weather and reject heat in summer months. Some key aspects of passive solar design include:
- Building orientation: The direction of building walls and apertures can influence the way sunlight impacts indoor lighting and temperature. For example, south-facing windows and doors can allow more sunlight into a building, providing more natural light and heat.
- Shading: During cold weather, a lack of shade from nearby buildings or trees can help maximize natural heat. In warmer weather, design features like awnings and shutters can help shade apertures from direct sunlight to keep the building cool.
- Thermal mass: Building materials with thermal mass are able to absorb, store, and release heat in a way that helps maintain comfortable ambient temperatures inside. One popular example is a Trombe wall, which uses convection to absorb and store solar radiation, providing slow and even heating to a building. This results in a 30 percent reduction in energy usage!
2. Roofing
The right choice of roofing material can help minimize heat gain in warmer climates. This is especially important in urban areas where heat island effects are prevalent. Some roofing options to consider for an energy-efficient building design include:
- Green roofs: Green roofs, also known as living roofs or vegetative roofs, are essentially rooftop gardens that serve to provide natural insulation and regulate indoor temperatures.
- Metal roofs: Metal roofing materials are known for their durability, reflectivity, and insulation properties. Especially when coated with reflective finishes, they can reject solar heat that would otherwise put a burden on air conditioning systems.
- Solar roofs: Solar panels convert sunlight into electricity through photovoltaic (PV) cells. In addition to providing a renewable source of energy, solar roofs can also insulate the building to some extent.
- TPO roofs: Thermoplastic olefin (TPO) roofing membranes are light-colored and highly reflective. They can help reduce heat absorption and keep indoor spaces cooler, leading to energy savings in cooling.
3. Windows
Windows are easily overlooked when planning an energy-efficient building, despite having a significant impact on energy usage. According to the Office of Energy Efficiency & Renewable Energy, windows have an impact on end uses that make up 40 percent of building energy use. In light of buildings being 40 percent of total energy use, window performance is responsible for 16 percent of all energy use in the U.S. That means they can directly and indirectly impact total energy usage in numerous ways.
Windows are often weak points in a building’s envelope with regard to energy and resilience, so making improvements in this area can instantly improve your building plans or upgrade an existing building. Some important considerations for energy-efficient windows include:
- Window materials: Choose energy-efficient glazing materials such as low-emissivity (low-e) glass, double or triple glazing, or insulated glass units (IGUs). A building sustainability partner can help you evaluate your options to choose windows that meet your requirements for energy efficiency, aesthetics, and budget.
- Window frames and seals: Some materials, such as fiberglass, vinyl, and wood offer superior thermal performance when it comes to window frames. Window seals should be properly weatherstripped to prevent air leakage. This involved ongoing maintenance to ensure a tight seal.
- Window coatings and films: Retrofitting windows with coatings can help maintain indoor comfort while reducing heating and cooling demands. Solar window film can allow the benefit of plenty of natural light deep into the interior of your building while minimizing the absorption of heat.
- Window inserts: At times a window insert (interior or exterior) can improve conductivity, infiltration, and solar heat gain—which in turn improve overall window performance.
Make Energy Efficiency a Top Priority in Your Building
For energy-efficient building design, it’s essential to look beyond the usual suspects like lighting and HVAC systems. Overlooked aspects such as passive solar design, roofing, and energy-efficient windows play a pivotal role in reducing a building’s energy consumption.
Have you explored these ways to potentially lower heating and cooling costs while lessening your environmental footprint? At NGS, we have extensive experience helping companies improve efficiency through solar window films, window inserts, and reducing air leakage. Now we’re leveraging our expertise in the area of energy efficiency to help companies consider the full breadth of solutions that could help them optimize energy efficiency in their buildings.
Learn how NGS partnered with First National Bank to improve the safety, comfort, and energy efficiency of commercial buildings with an expected 25 percent reduction in cooling costs and a more than 2 million ton reduction in CO2 entering the atmosphere!
