Add a Green Roof

The proportions of human-made surfaces to natural green space is constantly growing, as urban areas expand and density increases. Installing green roofs can mitigate this urban spread and reduce urban heat island effect.

A green roof, or eco-roof, is a roof that is fully or partially covered by vegetation planted over a waterproofing membrane. To function properly they require high quality water-proofing, a root repellent system, a drainage system, a filter cloth, a lightweight growing medium, and plants.

There are three kinds of green roofs: extensive, intensive, and semi-intensive. Extensive requires the least amount of soil and structural support but can hold limited plant diversity and are usually not accessible. Intensive can have soil depths up to several feet, so can be accessible and host a wide variety of vegetation but require more serious structural support. Semi-intensive is somewhere between these two systems.

Whether installed on existing buildings or implemented as part of the design for new construction, green roofs can offer a lot of benefits. Green roofs provide natural thermal insulation, helping reduce the energy load of a building. The increased vegetation also helps reduce greenhouse gases, filter the air of pollutants, and produce more, clean oxygen. This helps keep our air clean and slow the effects of climate change. They control water runoff and, depending on the kind of vegetation used, can also aid in saving pollinators populations. Lastly, they have significant mental health benefits, especially if they can be accessed as private or public space.

Installing a green roof may seem like a daunting task and it does take careful consideration and engineering, however, there are resources available to make it easier. Below are links that can help you understand the process and who to reach out to if you would like to install one on your current or future structure. This is a strategy that has immense potential benefits for the Duluth community and, if installed, would give the community a visual representation of your commitment to sustainability.

If you are interested in installing a green roof you can also check out the Unitarian Universalist Congregation of Duluth’s Green Roof which was installed in 2007, to get a sense of how this has already been done in our community.

Follow one of the links below for even more resources and information: