Master Streams Complete Practice Test 2026

For flat roof strip centers, the goal is to cover wide retail bays with minimal interior columns so the space remains open and flexible. Open web bar joists are designed to span long distances with relatively light members, giving you large column-free areas under a flat roof. The open web design also lets electrical, HVAC, and plumbing runs pass between the joist bays, making installation and later changes easier. They’re fast to install and cost-effective for this type of building, matching the needs of low-rise, repetitive retail bays. In contrast, reinforced concrete arches add weight and curvature that don’t fit a flat-roof, single-story retail layout; plywood decking is typically the deck material rather than the primary structural spanning element; and wood shakes are roofing material, not a structural system.