Side Wall Fittings Add either 1, 2, or 3 Side Walls. Canopy Parts Kits are user friendly and affordable. Canopy Size 20' x 20'Fitting Size 3/4\. Indications for a Flat Roof Canopy include but are not limited to greenhouses, RV and boat carports, batting cages, golf enclosures, and general shade structures for outdoor events/festivals, etc.