When the owners of this home first approached me – it was the beginning of the end of a multi-year project to build their dream home.

Nestled into a ridge wrapping the shores of a coastal lake, their home features two guest cottages and a workshop. Eric – homeowner & builder, had dreamed of someday having a living roof, and with that goal in mind, had engineered the structures to be able to support the weight that green roofs require.

Design Constraints

Now the challenge lay in selecting plants that could thrive in the unique coastal climate. While the site lay inland more than a mile from the ocean, it was still subject to big storms, and any plants used in the project would have to tolerate intense rain & wind. Conversely, the roofs would not be irrigated, and with only 3” of high draining media to grow in, the plants would need to be drought tolerant and able to survive the Summer. Growing media would be low in organic matter (to avoid settling & shrinkage over time), so plants would need to thrive on low nutrient environments. The two guest houses are situated with NE exposure, so they would need plants with higher shade tolerance. While the shop roof faced the West and would take the brunt of afternoon sun. Lastly, as part of a dream home, the roofs would be just one of the many components that made this property so special, and needed to provide significant wow factor, including ecological benefits to local pollinators.

Solutions

To tackle these design constraints, we selected species that originated in alpine & sub alpine environments in addition to native species from the pacific northwest that met specific criteria. We narrowed the palette based on plant morphology (how they grew), with the desire to have low growing, low maintenance species, and came up with a layout so that bold plant groupings would be visible from boats approaching the property from the lake. There was no data available for sites identical to this one, so we included some experimental plant varieties, like Licorice Fern (Polypodium glycyrrhiza), which I’ve observed growing in deeply shaded, high drainage locations. We narrowed our list to include 27 unique species. Needing to take advantage of a narrow Spring planting window, we chose to contract grow everything in 4” containers so that the plants would be ready and the same size at the same time.

One year after planting, everything looks great! Plants are establishing nicely, and even the Licorice Ferns have begun to put on new growth.

 
Nestled in the forested coastal mountains of Western Oregon, we created a stunning living roof that blends seamlessly with its natural surroundings while providing a haven for pollinators and other wildlife. The project began with careful consideration of the roof structure, soil, plants, and water. We accounted for drainage to ensure proper water flow. Next, we added a lightweight, nutrient-rich soil mix designed to support native, drought-tolerant plants such as wildflowers, and native grasses that thrive in the region’s climate with minimal maintenance. Positioned to complement the surrounding forest, the living roof not only enhances insulation and stormwater management but also offers a vibrant, green space teeming with life. This innovative feature highlights the beauty and sustainability possible when architecture harmonizes with nature.