Green certified homes are designed to optimize performance and energy efficiency. Unfortunately, the National Institutes of Health (NIH) recognizes a large discrepancy between a building’s energy performance as designed and the actual performance when monitored during the building’s operation and occupancy. To compound the issue, NIH found that over 50% of the energy consumption occurs in the absence of user activity. In other words, even when residents are leaving their homes, the home is still underperforming as compared to the designed energy performance.
There are a few ways to view this phenomenon. It is possible that because the homes are underperforming even when empty, the technology for enhancing or the methodology of predicting energy performance could be the culprit. Another method could be to focus on understanding and monitoring occupant behavior, then educate and incentivize residents to more efficiently use their homes.
The latter is an approach that continues to gain interest from the Department of Energy (DOE) and similar entities.
As an above code certification, the ICC 700-2020 National Green Building Standard (NGBS) dedicates an entire section to the operation, maintenance, and building owner education for all forms of residential construction. To further magnify the importance of the section, the chapter contains over five mandatory items for all projects seeking certification, and an additional requirement of earning not less than eight points for even the Bronze level NGBS certification.
Now that we have a high-level overview of the importance of the section – let’s dive deeper.
The intent of Chapter 10 of the NGBS is to ensure information on the building’s use, maintenance, and green components is provided to all responsible parties; to increase public awareness of the NGBS and projects certified through its robust and rigorous criteria; and to assess the building performance post-occupancy in order to correct any deviations in energy or water usage. Here are some of the practices from the chapter that can be applied to both single-family and multifamily buildings:
The building’s manuals ensure residents/responsible parties are knowledgeable of the efficiency measures included within their homes, the proper means of maintaining said measures and educated on their benefits. This multi-tiered approach aims to stress the importance and incentivize compliance through resource accessibility and projected cost savings.
Building owners or management are familiarized with the role of occupants in achieving green goals. Training is provided to the responsible party(ies) regarding equipment operation and maintenance, control systems, and occupant actions that will improve the environmental performance of the building to include HVAC filters, thermostat operation and programming, lighting controls, appliances operation, water heater settings and hot water use, fan controls, recycling and composting practices, and whole-dwelling mechanical ventilation systems.
The intent of public education is to amplify the reach of the NGBS and increase awareness of and demand for high-performance homes. The practice awards signage, certification plaques, and the sharing of the NGBS URL on the on-site signage, builder/property websites, etc.
The verification system (to be included in the building owner’s manual) measures the building's energy and water performance for comparison to expected performance metrics. This provides methods for demonstrating continued savings that are determined from the building’s initial year of occupancy of water and energy consumption as compared to annualized consumption at least every four years.
Energy rating, projected usage data, and/or an appraisal Institute Form 820.05 “Residential Green and Energy Addendum” or Form 821 “Commercial Green and energy Efficient Addendum” is posted in an appropriate location in the home, or public posting so that an appraiser can access the energy data for an energy efficiency and total property valuation and uploaded to a multiple listing service (MLS) or equivalent database so that appraisers can access it to compare property valuations.
NGBS Chapter 10 practices are focused on building optimization and occupant education, but they also have numerous benefits to the occupants including reduced utilities, increased resale value, reduced maintenance and replacement costs, etc. Involving and educating building occupants to achieve sustainability creates serious potential for cost savings and reduced energy consumption, and the 2020 NGBS has a comprehensive set of practices that can guide you towards that goal.
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