Double Gate Calculator (2 Leaves, Drop Rod)

Covers residential/agricultural swing gates only (single or double leaf) — not motorized/automated driveway gates or slide gates, which are a different product with their own track hardware and openers. The entered width is the gate's own finished width (combined across both leaves for a double gate), not the post-to-post frame opening — the frame opening needs to run 3¾ in wider (single gate) or 5½ in wider (double gate) than the finished width for hinge/latch hardware and swing clearance, shown above as Recommended Frame Opening. That 3¾/5½ in figure is per the CLFMI (Chain Link Fence Manufacturers Institute) installation guide — precise and sourced for Chain-Link gates specifically; for Wood/Vinyl/Aluminum it's carried over as a general planning starting point only, since those use different hinge/latch hardware with their own manufacturer-specific clearance needs — confirm the exact figure against your actual hardware before finalizing post spacing. A double gate's 2 leaves meet via a drop rod and ground sleeve, not a shared center post — 2 gate posts total either way. Gate posts are sized one nominal size up from a standard line post and buried 6 in deeper than the height/2 rule already used for fence posts, since a gate post alone carries the leaf's full weight and swing torque; footing hole diameter is ~3x the post width for wood/vinyl posts, and ~4x the post OD for chain-link posts specifically, per the CLFMI installation guide's own (larger) minimum. Wood: 2 stiles + 2 rails (3 past a 5 ft gate height) in 2x4, one diagonal 1x4 Z-brace per leaf running bottom-hinge-corner to top-latch-corner, 2 hinges per leaf (3 past a 4 ft leaf width). Vinyl: frame perimeter matched by an aluminum insert reinforcement inside the channel (priced separately from the frame), plus a diagonal turnbuckle CABLE kit running the opposite diagonal from a wood brace (top-hinge-corner to bottom-latch-corner, since a cable works in tension, not compression) and one molded panel insert per leaf. Aluminum: modeled as a pre-welded gate panel purchase per leaf (not a raw-material frame takeoff), matching how aluminum gates are actually sold; the optional Pool Code toggle enforces a 4 ft (48 in) minimum height and switches to self-closing/self-latching hardware and a larger-diameter post, per CPSC pool-barrier guidance / 2024 ISPSC Section 305 — the post dimensions shown are typical heavy-duty hardware manufacturer specs, not a dimension the code itself mandates, and this toggle reflects the material/hardware spec only, not a compliance certification. Chain-Link: welded tube frame sized to the leaf perimeter (tubing steps up a size past a 6 ft leaf), with a separate fabric mesh area; the gate post itself is a larger, separate-OD component from the frame tubing. Chain-link hinges are counted and sold as PAIRS — one male fitting (welds/fits to the gate post) plus one matching female fitting (welds/fits to the gate frame) per pair, per the CLFMI installation guide — so "2 hinge pairs" means 4 physical pieces (2 male + 2 female), and the hardware price for chain-link is per pair, not per individual piece. A blank waste factor defaults to 10%. This calculator computes material quantities only — it does not verify local fencing/gate-width ordinances, pool-safety inspection sign-off, or structural engineering for an unusually wide or heavy gate.