Application: Green Roof
Project: Hobbit House
Location: Knoxville, Tennessee
Photo courtesy of Lawn Butler

Summary

Building a Functional Green Roof on a Storybook Home
Nestled in the rolling terrain of Knoxville, Tennessee, the “Hobbit House” is a one-of-a-kind residential build that merges imaginative architecture with eco-conscious design. With a dome-shaped roof that slopes seamlessly into the earth, the structure called for a creative and resilient solution to support a living, vegetated roof. The homeowners needed a way to stabilize soil and prevent erosion on the steeply pitched roof without compromising aesthetics or sustainability.

Challenge

Stabilizing a Near-Vertical, Vegetated Roof
The design of the Hobbit House roof posed an extraordinary engineering challenge. Sloping steeply in all directions, approaching near-vertical angles in some areas, the surface made traditional green roofing techniques impractical. The risk of soil erosion was high, and standard stabilization methods lacked the flexibility and structural support needed for the unique geometry. A lightweight, adaptable, and secure system was essential to make the vegetated roof both viable and sustainable.

Solution

GEOWEB® Geocells Provide Strength and Flexibility
To meet these demanding requirements, the GEOWEB® Slope Protection System was chosen for its unmatched performance in steep slope stabilization. Manufactured by Presto Geosystems and distributed by Jen-Hill Construction Materials, GEOWEB Geocells create a 3D structure that confines and secures soil, making them ideal for irregular and inclined surfaces. Installation was expertly executed by Lawn Butler using approximately 6,000 square feet of GEOWEB panels.

The system was anchored with ATRA® Keys, tendons, and ATRA Tendon Clips, ensuring maximum resistance to sliding and gravitational forces. This geocellular solution formed a stable framework to support vegetation, enabling the successful installation of sod on an otherwise unmanageable slope.

Results

A Thriving Green Roof with Lasting Impact
The GEOWEB System transformed the Hobbit House’s challenging roof into a lush, green oasis. The geocells stabilized the soil effectively, allowing sod to establish and thrive while eliminating concerns of erosion or shifting over time. The final result exceeded the homeowners’ expectations, delivering a visually striking, eco-friendly roof that provides natural insulation and blends seamlessly into the landscape. With low maintenance requirements and enduring performance, the project stands as a model of sustainable, imaginative design enabled by smart engineering solutions.