The structural framing of an attached covered patio — the posts, beams, and rafters that form the skeleton of the structure — is sized by the Broken Arrow building code based on the loads the structure must carry, the span between supports, and the lumber species and grade used. Understanding how post and beam sizing works helps Broken Arrow homeowners evaluate whether a contractor’s proposal specifies adequate structural members for the covered patio’s configuration, and why a larger covered patio requires heavier framing than a smaller one. VistaScapes & Design specifies all covered patio structural members per the Broken Arrow building code requirements and includes the structural specification in every written proposal.
Post Sizing for Broken Arrow Covered Patios
Posts in a Broken Arrow covered patio carry the combined dead load (roof framing, sheathing, and roofing — approximately 12 to 18 pounds per square foot for a standard shingle roof) and live load (20 pounds per square foot per Broken Arrow code) from the roof tributary area above each post. Post sizing for typical Broken Arrow covered patio configurations: 4×4 posts — acceptable only for covered patio structures with a post height under 8 feet and a tributary area per post of under 64 square feet (an 8-foot post spacing in a simple shed roof configuration); 4×4 posts flex and fail at heights above 8 feet and are not appropriate for most full-height attached covered patio structures in Broken Arrow. 6×6 posts — the standard specification for Broken Arrow covered patios with post heights of 8 to 12 feet and tributary areas of up to 96 square feet per post; 6×6 posts are visually proportionate to the beam and rafter sizes appropriate for a full-sized covered patio and are the minimum specification recommended by VistaScapes & Design. For covered patio structures with post heights exceeding 12 feet (a vaulted ceiling design or a raised addition above an existing patio elevation), engineered posts or steel tube column inserts may be required by the structural plan. Post footings in Broken Arrow: each post must bear on a concrete footing sized per soil bearing capacity and the post load; typical Broken Arrow covered patio footings for 6×6 posts are 12-inch diameter by 18-inch deep poured concrete piers (formed with a Sonotube) in firm soil; the footing depth must exceed the local frost depth (approximately 18 inches in Broken Arrow per the IBC climate zone designation); a post base connector (Simpson Strong-Tie ABA or equivalent) connects the pressure-treated post to the footing and prevents the post end from sitting in water-contact with the concrete.
Beam and Rafter Sizing
Beam sizing for a Broken Arrow covered patio: the beam spans between posts and carries the rafter load; beam size is determined by the span between posts and the roof tributary width. For a standard Broken Arrow covered patio with posts at 8-foot centers and a 16-foot roof span (8 feet from the ledger to the outer beam): a 2-ply 2×10 or 2×12 (#2 Southern Yellow Pine) beam is the standard specification for an 8-foot post spacing; a 3-ply 2×12 or an engineered LVL (laminated veneer lumber) beam is appropriate for post spacings of 10 to 12 feet or where the beam carries a wider roof tributary area. Rafter sizing: rafters span from the ledger board to the outer beam and are sized by the span length and the rafter spacing; for a 16-foot rafter span at 24-inch on-center spacing: 2×10 rafters (Douglas Fir or Southern Yellow Pine, #2 grade) are the standard specification; at 16-inch on-center spacing, 2×8 rafters may be adequate for a 16-foot span depending on the applied load and species. Rafter hardware: Simpson H2.5 (or equivalent) hurricane ties connect each rafter to the beam at the outer end and to the ledger at the home attachment end; these connectors are required by the Broken Arrow building code and are inspected during framing inspection. Covered patio roof pitch: a minimum 3:12 roof pitch (3 inches of rise per 12 inches of run) is required for asphalt shingle roofing — pitches below 3:12 require modified bitumen or standing seam metal roofing; most Broken Arrow covered patio projects target a 4:12 to 6:12 pitch for visual proportion and adequate drainage. VistaScapes & Design specifies all structural members per the Broken Arrow building code tables and provides the specification in the written proposal for every covered patio project.
Call VistaScapes & Design at (918) 779-1317 for a free covered patio consultation in Broken Arrow. We’ll explain the structural specification for your specific covered patio design and what the building code requires for your project.
