Grow1 Heavy-Duty Greenhouse Hoop House - 20ft x 10ft x 6.5ftCreate a protected, high yield grow space with this durable 20 foot hoop house designed for season extension, airflow, and easy setup in any climate. Commonly called hoop houses, high tunnels, or cold frames, non engineered greenhouses are hands down the best bang for your buck when installing an enclosed growing space. These greenhouses feature sturdy steel frames. If you can turn a wrench, you can build one of these sturdy greenhouse structures.