“Small actions can lead to big change,” said Alejandra Hinojosa, Affil. ASLA, sustainability specialist with LPA Design Studios.
“You don’t need to feel defeated. You may not accomplish all your climate goals in a project, but that’s not a failure. You can make progress in your next project. Be empowered.”
Last year, Hinojosa and Mariana Ricker, ASLA, associate principal at SWA, published Decarbonizing the Design Process: A Phase by Phase Approach for Landscape Architects.
In an online discussion, Hinojosa said the guide outlines how to make “intentional low-carbon design decisions, address broader environmental impacts, and advocate for better projects.”
“The guide is designed to helpful no matter what stage of the design process,” Ricker said.
The first step is to establish a decarbonization strategy for a landscape architecture project. “It’s best to do that at the beginning, but it’s not impossible to add it in at a later phase,” Hinojosa said.
For clients who may need extra persuading, landscape architects can frame the benefits of decarbonization in terms of “people, the planet, and profit.”
Hinojosa focused on the profit part. There is a clear return on investment for low-carbon projects: “They have lower operational costs.” And these projects offer many co-benefits in terms of healthier materials, more green space, and increased biodiversity.
As designers move into the schematic design phase, they should focus on three big ideas to reduce emissions:
1) Maximize the reuse of materials found on site
2) Incorporate low-impact design, such as green infrastructure
3) Choose low-carbon materials and create more space for soils, plants, and trees to sequester carbon
Overall, it’s also important to reduce materials as much as possible. For example, “reducing cement saves clients money and reduces embodied carbon. It’s a win-win,” Hinojosa said.
These approaches can also be “seamlessly woven” into a project. “What does low-carbon design mean? It’s just part of the vision for a project.”
Later stages of a landscape architecture project also provide opportunities to reduce emissions. Ricker said landscape architects will benefit from talking to product manufacturers about their product and material emissions.
Designers can collaborate with industry partners. They can ask for Environmental Product Declarations (EPDs), which are third-party verified accounts of the environmental impacts of a product.
Ricker outlined some key strategies for decarbonizing design details:
- Use local products and materials
- Reduce cement use
- Use as much wood as you can
- Use recycled steel products only as needed
- Use low-carbon aggregates and fills
- Protect and reuse soils
Another session delved into how to decarbonize the design specifications that guide the construction of landscape architecture projects.
Last year, Chris Hardy, ASLA, senior associate at Sasaki and founder of Carbon Conscience, led the development of Decarbonizing Specifications: Guidelines for Landscape Architects, Specifiers, and Contractors.
In another online discussion, Hardy said “every construction project, every material has a global warming impact.” Using the new guidelines can help cut those impacts.
The “guidelines aren’t technical standards; they can’t be copied and pasted into specifications,” but they can guide the revision of specifications.
Busy landscape architects can start with updating their specifications for concrete, which can account for more than 50 percent of the emissions of a project. Hardy said Sasaki recently updated its concrete specifications, resulting in significant emissions cuts.
The guidelines also offer ways to reduce emissions by specifying low-carbon products, materials, and construction practices in other areas, like unit masonry, stone, metals, carpentry, base courses and aggregates, lightweight fill, trees and plants, and more. And Decarbonizing Specifications also covers how to best reuse materials and reduce construction waste.
Landscape architects can take a few approaches to updating their specifications:
- Update office standards
- Update specifications project by project
- Edit specifications in SpecLink or MasterSpec
- Educate external specification writers
The process is worth it: “We can buy less stuff, cut unnecessary embodied carbon, and save clients money.”