The intent of Ch. 6 is to minimize environmental impact through design, material selection, & construction.

Deep Dive into NGBS Chapter 6: Resource Efficiency

November 2, 2022

***

The American Institute of Architects predicted 9% growth in the residential construction sector in 2022 alone. The residential sector’s high growth rate will demand significant resources, but when resource efficiency measures are employed, we can use less.

Resource efficiency is the technique of minimizing resource exploitation and ensuring that structures can function for an extended period and withstand natural disasters. This is achieved through measures including reduction of primary and non-renewable materials, creation of high-quality products with minimal waste and retention of durable products, and durable construction practices. Various design techniques, construction practices, and choice of materials can help optimize resources used in construction.

Resource efficiency practices are not nearly appreciated by high-performance and sustainability advocates as they should be. First, these green practices are often hidden behind walls and finishing materials and so they are harder to sell to future residents. Second, implementation of these practices can reduce construction costs which in turn can allow the builder to invest more in green practices that do cost more money.

The ICC 700-2020 National Green Building Standard™ (NGBS) Chapter 6 has them covered – lets dive deeper.

The intent of Chapter 6 of NGBS is to minimize environmental impact and improve performance (energy efficiency, resiliency, and durability) of the building through a range of practices that allows informed decision making during the design, material selection, and construction. Here are some of the practices from the chapter that can be applied to both new construction or renovation to achieve a greener, more sustainable environment while saving on utility bills and maintenance costs in the long run:

Quality of construction materials and waste: A simple and sure way to improve sustainability of the house is by reducing the conditioned floor area – the smaller area the better. Similarly, the structural system can be designed to reduce and optimize material use – an example is adopting advanced framing technique that uses minimum structural member or element size necessary for strength and stiffness. Higher grade, or higher strength, of the same materials can also be used to reduce component size of the building. Use of prefabricated components help reduce waste while providing a higher quality product. Likewise, the building footprint can be reduced by increasing the number of stories above grade instead of a single-story house with larger floor area.

Enhanced durability and reduced maintenance: The durability of the house can be improved through implementation of proper moisture management of building envelope, termite resilience construction, provision of ice-barriers, roof overhangs, etc. It is also important to select durable materials in addition to applying efficient construction techniques to improve the overall durability of the house.

Reused, recycled, and renewable materials: Reusing the existing building material for renovation, or using salvaged materials during demolition, optimizes resources while saving cost. Use of building materials with recycled content is also a better choice if sustainability is the overall goal. Practices like onsite recycling and having a construction waste management plan help reduce waste and lessen environmental impact. Simple choices like selection of renewable materials over non-renewable also makes a significant difference to the environment. An example of this is using bamboo flooring, which is more sustainable than traditional wood flooring as the harvest cycle of a bamboo is 3-4 years compared to roughly 25 years for traditional wood.

Resource-efficient and regional materials: Examples of resource-efficient materials include engineered wood or engineered steel products, thinner and lighter brick, and fewer materials used for various components like roof or floor trusses. Choosing regional materials instead of choosing materials that require long distance transportation is clearly more sustainable.

Life cycle assessment (LCA): This includes the use of LCA tool to select environmentally preferable products, assemblies, or entire building designs.

Innovative practices: Practices including universal design elements that makes a house more accessible and use of sustainable products that are certified by a third-party agency can be selected to maximize building occupancy and avoid future renovations.

Resilient construction: Designs and construction practices developed by a licensed design professional to improve resiliency of the building can be selected in areas prone to natural disaster.

While the practices discussed are focused on resource optimization and sustainable construction, it also has numerous benefits to the occupants including, improved occupant health and productivity, increased resale value of the building, reduced maintenance and replacement costs, etc. Applying resource efficiency to achieve sustainability involves careful consideration during planning and design phase and requires a whole building systems approach – the 2020 NGBS has a comprehensive set of practices that can guide you towards that goal.

A list of Green Products is provided in the Home Innovation Research Labs website which can guide builders and homeowners identify third-party certified and resource efficient products to earn points toward NGBS Green Certification.

***