How to Build a Backyard Deck

D eck building is the ultimate test of a weekend warrior's patience and planning. It is far more than just laying down boards; it is an exercise in geometry, structural load calculation, and weatherproofing. A deck done well sits perfectly level with your home's threshold, drains water away from the structure, and feels solid as a rock under every step you take. When you approach this, respect the weight. You are creating a platform that must support furniture, guests, and the immense weight of wet, pressure-treated lumber. Don't rush the framing phase. If your joists aren't square and true, your final surface will look messy no matter how high-quality your finish boards are. Take your time with the layout strings and the concrete footings, as those are the only parts of this project you cannot easily fix once the decking goes on.

  1. Square Your Foundation First. Measure your perimeter and drive stakes at each corner. Use the 3-4-5 triangle rule to ensure the corners are perfectly square, then run high-tension mason's line between the stakes.
  2. Dig Deep, Dig Level. Dig holes for your concrete piers below the frost line in your area. Insert cardboard tube forms, level them, and pour high-strength concrete mix, embedding adjustable post bases before the concrete sets.
  3. Anchor to Your House. Bolt the ledger board to your house rim joist using heavy-duty lag screws. Use galvanized flashing behind the board to prevent water from wicking into the house structure.
  4. Build the Skeleton Square. Attach the main support beams to your post bases, then use metal joist hangers to connect your joists from the ledger board to the outer rim joist. Space joists 16 inches on-center for maximum stiffness.
  5. Crown Up, Drain Right. Start at the house and work outward, securing each board to the joists with two deck screws per support. Use a nail or spacer between boards to ensure consistent drainage gaps.
  6. Seal and Protect. Install structural posts for the railing, then attach balusters and a top rail. Apply a high-quality deck sealer or stain to protect the wood from UV damage and moisture.