Piers: 12 total (2 rows × 6) · 8" dia. × 4' deep · ABA ZMAX post bases · Pier tops ~4" above grade ·
Beams: Doubled 2×6 PT UC4B — Ply 1 joints at 8'&16', Ply 2 joint at 4' (4' offcut + 16' board) ·
Joists: 2×6 PT @ 16" OC hung in LUS26 joist hangers flush with beam top ·
20' ÷ 16" = 15 exact bays — no partial bay · Mark both beams from same end to keep joists square
Pier Layout — Chalk Line Positions
Hook tape at 0' (same corner on both rows) · Mark at each position · Snap chalk line or use string line ·
Critical: measure diagonals (0' front to 20' back, and 20' front to 0' back) — they must be equal to confirm square ·
Dig holes, set QUIK-TUBE forms, place gravel base, pour concrete, set post base anchor bolts in wet concrete
Doubled Beam — Splice Detail
All joints must land directly over a pier — no mid-span splices ·
Ply 1 joints at 8' and 16' (boards: 8'+8'+4') ·
Ply 2 joint at 4' only (boards: 4'+16') — staggered so no two joints align vertically ·
Laminate with 16d galvanized nails, 2 rows staggered every 16" OC ·
Start with Ply 1, then nail Ply 2 on top