Project description
Every post sits on its own footing rather than just resting on the soil. Holes are dug below the local frost line, a gravel base is tamped in for drainage, and the post is set in a concrete footing with a galvanized post base or anchor bolt so the wood itself never touches wet ground. On a pergola this is what keeps the whole frame from racking sideways over the years. Beams are through-bolted to the posts rather than toe-nailed, and rafters are notched or hung on joist hangers for a clean, strong connection.
For a trellis, the climbing surface is either a diamond or square lattice panel, a grid of horizontal wires on eye screws, or evenly spaced vertical slats, chosen to suit the plant: roses and clematis like an open grid, while grapes and wisteria want sturdier horizontal runs that can take real weight as the vine matures. On a pergola the rafters themselves can be spaced tighter or wider to tune how much shade versus dappled light comes through.
All lumber is sanded, edges eased, and hardware set below the surface before two coats of exterior stain or a water-repellent sealant go on; cedar is often left with just a clear UV-protective sealant to weather naturally. Typical timeline: one visit to measure and confirm the layout, two to three days to build and pre-finish the frame components, one to two days on site to set footings and assemble, plus a return visit once the concrete has cured to check bolts and touch up the finish.