80×120 Equestrian Arena with Wing — Clackamas County, Oregon

An 80-foot-wide, 120-foot-long riding arena with an attached 24×120 shed-row wing on a working horse property in the Sandy area of Clackamas County, Oregon. The arena is fully clear-span from sidewall to sidewall — no interior posts in the riding area — sized for the snow and wind loads typical of the western Cascade foothills.

At 80 feet of width, the engineering moves past standard pre-fabricated trusses into heavier engineered commons set on 6×12 eave-wall posts. The arena runs an 18-foot eave, which keeps clearance well above a mounted rider and lets the operation work horses under cover year-round without compromise. Two 14×14 overhead doors centered in each gable end give equipment access through the full length of the arena for footing maintenance and harrowing.

The 24-foot wing runs the long side of the arena with a 2-foot eave drop between the two roofs, so the shared wall reads as one continuous structure rather than two buildings shoved together. Three walls of the wing are closed to grade and the wall facing the arena is left open, which lets the wing function as a covered shed-row directly off the riding floor. Eight 4×8 sliding paddock doors on the outboard eave wall give each stall area its own access to a turnout. Wood-sided sliders with diagonal X-bracing on the gable ends finish the look the owner wanted.

Natural light comes from polycarbonate skylights running the full 120-foot length of both arena eave walls — a wider 4-foot band on the closed side, a 2-foot band above the wing — plus a matching band on the wing’s outboard wall. Two cupolas vent the arena ridge. Charcoal grey Tuff Rib steel siding and roofing with Glacier White trim throughout, which is a common color pairing on Clackamas County horse properties and weathers cleanly under wet winters.

The Sandy corridor along Highway 26 sits in working-horse country — established equestrian operations and family riding facilities scattered across the foothills east of Boring. Buildings of this scale need to handle Cascade-foothills snow loads without overbuilding the rafter package, and they need to read as horse facilities rather than industrial sheds. The skylight strategy and the dropped wing eave do most of that work. The shell went up through late summer and fall of 2017.