How to Build a Deck

Building a deck is the ideal home improvement project for the average handy man or woman. No advance carpentry skills or expensive tools are needed to build a useful and beautiful deck that will add style and value to any home.

Materials

  • 5×4 inch decking lumber
  • 2×8 pressure-treated lumber
  • 2×10 pressure-treated lumber
  • Fibreboard pier form
  • Plastic footing form
  • Concrete
  • Ledger fasteners
  • Polyurethane sealant
  • Face mounted joist hangers
  • Post bases
  • Masonry expansion bolts
  • Siliconised acrylic caulk
  • Metal flashing
  • 6D,12D and 16D galvanised or stainless steel common nails
  • 8D Galvanised or stainless steel finish nails
  • 5/8-inch roofing nails
  • Self-adhering waterproof membrane
  • Concealed-flange and face-mounted double joist hangers
  • Hanger nails
  • Construction adhesive

Tools

  • Hammer-drill with masonry bit
  • ½ inch drill with 3/8 inch bit
  • Socket wrench
  • Plumb bob and string
  • Circular saw
  • Level
  • Chalk line
  • Concrete mixer
  • Hammer
  • mpact wrench
  • Shovel
  • Tape measure
  • Utility knife

Building instructions

Attaching and protecting the ledger

  1. Remove the building’s trim and siding to 1 foot above the top of where the ledger will sit.
  2. Cover exposed sheathing with self-adhering waterproof membrane.
  3. Mark the exact location of the top of the ledger.
  4. Any step down to the finish decking, which sits atop the ledger, must be 4 to 7 ¾ inches below the door sill.
  5. Snap a level chalk line.
  6. Cut a 2 inch wide, 1 ½ inch thick treated wood spacer for every 2 feet of ledger length.
  7. Align the top of each spacer with the chalk line and fasten with a 6D nail.
  8. Align the ledger with the tops of the spacers and nail it to the wall at each spacer with the 16D nail ensuring Joints between ledger boards fall on a spacer.
  9. In a zigzag pattern, drill a 3 3/8 inch pilot hole through the ledger and into the house’s rim joist at each spacer.
  10. In each hole, insert a ½ inch lag screw and tighten it against a washer using an impact or socket wrench.
  11. Cut a strip of self-adhering waterproof membrane 6 inches wide and the same length as the ledger.
  12. Fold the membrane length wise along its centre line forming a right angle.
  13. Apply it over the ledger-to-house joint so one leg covers the top of the spacer block and ledger and the other leg extends up the wall.
  14. Cut a strip of metal flashing at least 6 inches wide and as long as the ledger.
  15. Fold the metal length wise to form a right angle. Apply it over the waterproof membrane.
  16. Drive roofing nails through the top edge of the flashing, every 8 inches.
  17. Fasten concealed-flange double joist hangers at both ends of the ledger and flush with its bottom edge, using joist hanger nails.

Setting footings and piers

  1. Set up batter boards and mason’s strings and determine footing locations at the deck’s outside corners and at 8-foot intervals along the front rim joist.
  2. Mark each location then remove the mason’s strings temporarily.
  3. Dig a hole wide enough to hold the footing form and deep enough to extend below the frost lone at each footing location.
  4. Assemble footing and pier forms according to the manufacturer’s instructions then position one in each hole. Gently back fill.
  5. Run a level line from the top of the ledger to the pier tube and from this line to determine each pier’s finish height.
  6. From this line, measure down 1/16 inch per foot of the pier’s distance from the house, plus the height of the rim joist and post base.
  7. Mark the form at this point and repeat for each pier.
  8. Trim pier tubes at these marks.
  9. Check the positioning of the piers and adjust if necessary.
  10. Fill with concrete using a shovel to work out air pockets.
  11. Allow the concrete to cure for a week.

Installing post bases and side rim joists

  1. Place a post base on a pier, position it so it will not interfere with joist hangers, and mark its location.
  2. Remove post base and bore into pier with a hammer drill equipped with a masonry bit.
  3. Reposition post base, insert an anchor bolt, and tighten with an impact wrench.
  4. Repeat for each pier.
  5. Cut pressure-treated 2x stock for the doubled side rim joists and beams.
  6. Glue them up with construction adhesive and nail them together from both sides with 12D nails, spaced every 16 inches in a zigzag pattern.
  7. Fit a side rim joist into a hanger at one end of the ledger, square the corner and toenail through the hanger into the ledger with 16D nails.
  8. Rest the joist’s opposite end on a corner pier.
  9. Repeat with the other side joist, removing mason’s strings as necessary.
  10. Cut pressure-treated 2x stock for the deck’s front rim joist.
  11. Stagger any butt joints by varying board lengths, ensuring joints fall in the middle of post anchors.

Installing front rim joist, beams and interior joists

  1. Fasten concealed-flange double joist hangers on the ends of the front rim joists inner 2x’s.
  2. Fit the inner 2x’s into the post bases.
  3. Fit a side rim joist into a front hanger and square the corner.
  4. Secure front rim joist 2x to the post bases with hanger nails. Drive the six 16D nails through the face of the front rim joist into the end of the side rim joist.
  5. Repeat with the other side rim joist.
  6. Fasten face-mounted double joist hangers for beams every 8 feet on centre along the front rim joist and ledger, flush with bottom edges.
  7. Fit and nail each beam as described above.
  8. Glue and nail the outer 2x’s to the inner 2x’s.
  9. Install 2x joist hangers along the beams, 16 inches on centre.
  10. Fit and toenail joists through hangers.

Attaching trim and decking

  1. Nail paint-grade trim boards as wide as the rim joists to their outside faces with two 8D hot dipped galvanised finished nails spaced 12-16 inches apart.
  2. Scarf any joints in the run; miter joints at the corners.
  3. Measure distance from wall to the outside of the trim board and add 1 inch for overhang. Cut the deck boards to this length.
  4. Squeeze a bead of polyurethane sealant on the top edge of a side rim joist.
  5. Lay a straight deck board in the adhesive so its long edge overhangs the trim board by 1 inch.
  6. Secure each end of the deck board with an 8D finish nail.
  7. Tack 8D finish nails alongside the first board to maintain consistent spacing.
  8. Squeeze dabs of adhesive onto the top edge of each joist.
  9. Lay and nail the next deck board as before.
  10. Continue gluing and nailing until deck is complete.
  11. Replace house’s siding within ½ to an inch of the decking.

Tips and warnings

  • Decking laid at right angles to the house makes for a stronger front edge.
  • If the joist has a crown install it crown-side up.