Hemp Follows Function
In architecture, there is a foundational principle of good design. Form should be driven by function. Otherwise, the building might be stunning to observe, but a tremendous challenge to use. Not only is this wasteful, it’s also disrespectful to the occupants.
Waste comes in many forms. Unused space, inefficient mechanical systems, and high embodied carbon materials like concrete and steel.
Today, Bob Escher, AIA and Jennifer Martin invited architects throughout AIA Wisconsin and AIA Chicago to radically turn the tide on carbon in the built environment. We introduced hempcrete as a high-performance building material that is carbon positive.
Carbon Positive
A city, development, building, or product that goes beyond carbon neutral to create an environmental benefit, and intentionally removes carbon dioxide from the atmosphere and turns it into useful forms.
To frame the conversation, and the importance of shifting to carbon-positive materials, Bob championed the leadership of the American Institute of Architects (AIA). Partnering with Architecture 2030, AIA’s Architect Magazine kicked off 2020 with the Carbon Issue, which features a stark iconographic cover and the feature article It’s Time to Quit: A Call to Action on Climate, Carbon, and the Built Environment
The AIA makes a bold call to its professional membership to STOP business as usual and devise new ways of building.
Modern architecture must consider not only form and function, but also the responsible use of materials. Today, carbon emissions from Core and Shell material manufacture accounts for 11% of all infrastructure energy used globally.
Thus far, the construction industry has been focused on lowering the operational carbon of buildings - shown in this pie chart as Building Operations. We’ve done some significant work in this area, and will continue to do so.
However, it’s timely and imperative to tackle carbon that is produced from the manufacture of building materials - totaling 21% of all energy used globally.
The time is now.
We need to utilize materials that are plant-based (renewable), abundant, and respectful to the ecological systems from whence they came. This means local and sustainably grown and harvested.
Hemp is one such solution. Hempcrete is a powerhouse at absorbing carbon.
Structural materials have a big impact on the carbon footprint of a building.
Changing the Way We Build
Steel, concrete and foam dominate the world of Architects. These materials all happen to be high in embodied carbon.
Embodied Carbon
The CO₂ emitted during the extraction, manufacture, and transport of building materials and products, and the construction of buildings and infrastructure
In order to turn the tide on the embodied carbon of the materials we select, we need to shift from a predominant use of these high embodied carbon materials to a predominant use of carbon-positive, or carbon-smart materials.
Hemp is the epitome of carbon positive – hemp creates an environmental benefit by intentionally removing carbon dioxide from the atmosphere and turns it into a useful form - a woody core.
This woody core is then chopped up and coated in a lime-based binder to make hempcrete. Placed within a building envelope, the carbon captured by the hemp plant stays locked away for the life of the building.
Best of all, hemp plays well with other carbon-positive materials to create bio-composites that can and will replace the many carbon-polluting materials of construction today, from insulation and wood alternatives to bio-plastics and paints. So keep your eyes peeled for new hemp-based building solutions yet to come.
Source: Carbon Smart Materials Palette https://materialspalette.org/
from left to right
1.Recycled plastic
2.Rice straw
3.EcoSmart Wall board panels
4.Bamboo
5.Recycled aluminum
6.Wood fiber
Where’s the Hemp?
Despite the many benefits of hemp, it’s still a newcomer to the building industry, and a relative unknown.
The Carbon Issue highlights 8 low-embodied carbon materials, but hemp doesn’t make it on the list. The reason for hemp’s absence is that the hemp industry is still in its infancy.
Bob Escher, AIA member and founding President of the US Hemp Building Association, is not deterred. He understands that the development of a robust hemp building industry will take years to establish. Instead, as an architect, Bob is excited to be a part of creating a new building genre using a once-in-a-lifetime new construction material.
Hemp is coming, and it will change the way we build.