Leadership in Energy and Environmental Design (LEED), is a comprehensive and complex certification program for green building. Developed in the 1990s by the non-profit US Green Building Council (USGBC), it now guides sustainable construction in more than 160 countries. LEED looks at every component of a building — from site selection and construction techniques to appliances and furnishings — with the goal of making buildings safe, environmentally friendly, and energy efficient.

Sustainability begins at home

Although LEED is often associated with prestige buildings like Vancouver’s grass-roofed convention centre or Facebook’s water-efficient headquarters in California, LEED also certifies apartment, condo, and single family home construction. Projects earn points for meeting requirements like careful construction-waste disposal and optional features like rainwater management. The number of points earned determines the level of certification awarded: certified, silver, gold, or platinum.

LEED guidelines differ depending on project type. Under the most recent standard for residential construction, credits are offered in eight categories: location and transportation (encourages building on previously developed lots and avoiding sensitive land); sustainable sites (minimizing impact of construction and building on local ecology); water efficiency; energy and atmosphere; materials and resources; indoor environmental quality (eliminating contaminants like formaldehyde and mold); innovation; and regional priority (credits for elements important to the region of construction).

A LEED home is not a DIY project. It usually requires accredited architects and project managers, and contractors that understand specific techniques.

Homes earn points for being close to a bike network and within 800 meters of resources like stores, cafés, schools and libraries. Woods and materials must be environmentally sustainable, and/or extracted, processed, and manufactured locally. Points are awarded for using recycled materials. Inside, appliances and water systems must be efficient. A LEED-certified home should be oriented to benefit from passive solar heating and be sized appropriately — the LEED reference home assumes 205 square metres for a three-bedroom home.

A LEED home is not a DIY project. Building one usually requires architects and project managers with LEED accreditation, and contractors that understand principles and techniques specific to LEED.

Certification is a multi-stage process. Residential projects are required to have a LEED-approved Green Rater as part of the project team. Green Raters have at least three years of experience in residential construction, a thorough understanding of LEED practices, and complete a short training course offered by USGBC. They must be involved from the design phase of the project and throughout the construction process, doing an on-site verification to confirm LEED specifications have been met.

After construction, they assemble the package for final review by a country’s green building council. USGBC charges builders to register a project (ranging from US$225 per detached home up to US$5,000 for a city) and again for the review (US$300 for a house, in the tens of thousands for large projects).

Open questions

Since its creation in 1998, LEED has had detractors. LEED projects can be less energy-efficient than claimed; a 2019 review published in the journal Sustainability concluded that “energy efficiency of LEED-certified buildings is questionable especially at lower levels.”

One example: a 2013 New Republic article described a Manhattan skyscraper as “Bank of America’s Toxic Tower” for its high greenhouse gas emissions per square foot. The USGBC rebuttal appeared with the article, pointing out the author had ignored features that made the building efficient, and that builders and certifiers have no control of how occupants use a building: “These unanticipated changes could indeed impact a project’s energy use.”

More recent versions of LEED have tried to address the occupancy issue with the Building Operations and Maintenance certification. This framework provides a way of assessing the actual energy-use of occupied buildings, but it is optional.

One common perception of LEED is that it’s “crazy expensive,” says Joanne Sawatzky, a managing director at Light House Sustainability Society, a non-profit focused on creating a sustainable built environment. In fact, Sawatzky says, building to the LEED standard costs 1–5% more than a conventional building. LEED claims that decreased spending on energy and other expenses offsets that investment in only a few years, though that would depend on energy savings being realized.

There is a belief that applicants and their consultants “game the system” by going after low-hanging fruit to rack up a good score.

Another criticism is that LEED is more about “greenwashing” than actual environmental sustainability. Kaid Benfield, who co-founded LEED’s Neighborhood Development rating system, observed in a 2013 critique: “there is a belief that applicants and their consultants ‘game the system’ by going after low-hanging fruit to rack up a good score, even if the underlying measure doesn’t result in a significant environmental improvement.”

However, critics including Benfield acknowledge that, despite its weaknesses, LEED has made environmentally responsible building easier and has given developers a business case for green building. LEED’s oversight body, the USGBC, seems willing to look at shortcomings and make changes in each revision of the system (we’re currently on version 4.1).

Following LEED’s lead

LEED remains the best-known measure of sustainable design and construction, especially for large, high-profile buildings. But developers and homeowners have many options when planning a project. Sawatzky mentioned a system called Built Green she says is popular in Alberta, which offers certification and training for homebuilders. This program is “more like a checklist of items which is a lot easier for standard home builders to understand,” says Sawatzky. “It really lays things out very simply where LEED has layers.”

And in BC, where Sawatzky is based, the BC Energy Step Code offers builders and renovators a flexible system of “steps” that will “make buildings net-zero energy ready by 2032.” The Germany-based Passive House Institute has a similar step-by-step system for designing and building homes with low energy use.

“LEED remains the best-known rating system for green buildings,” says Sawatzky. “However, other rating systems are picking up momentum as they align with specific municipal or provincial mandates for reduced energy and carbon emissions.” Although other systems might be less comprehensive than LEED, they’re helping move home construction toward more ecologically responsible practices.

Buzzword summary

Comprehensive and internationally recognized. Critiqued but regularly updated.