Build a 32’ x 24’ Platform Deck

Materials & Tools You'll Need

Materials:

  • Pressure-treated lumber (joists, beams, and decking boards)

  • Concrete deck footings or pier blocks

  • Galvanized hardware (joist hangers, lag screws, deck screws, bolts)

  • Gravel or crushed stone for drainage

  • Exterior-grade wood sealant or stain

Tools:

  • Tape measure

  • Circular saw or miter saw

  • Power drill and impact driver

  • Level

  • Framing square

  • Post hole digger (if using concrete footings)

  • Shovel

  • String line and stakes

Step 1: Plan and Prepare

1. Check Local Building Codes: Ensure your deck complies with local regulations. Since it's low and without railings, codes may still specify structural requirements and footing depth.

2. Mark the Area: Use stakes and string to outline the 32' x 24' deck. Verify it's square by measuring diagonally (both diagonals should be equal).

3. Prepare the Ground:

  • Remove grass or vegetation in the deck area.

  • Ensure area is level - measure with a level. You may need to get help grading.

  • Lay down landscape fabric to prevent weed growth and cover with at least 2” of gravel for drainage.

Step 2: Install Footings

1. Determine Footing Layout:

  • Place footings every 6-8 feet along the perimeter and under joist spans to ensure even weight distribution. For a 32' x 24' deck, you'll need approximately 12–16 footings.

2. Install Footings:

  • Dig holes to the required depth for frost lines (if applicable).

  • Set concrete footings or pier blocks in the holes and ensure they are level.

  • If using concrete, allow it to cure before proceeding.

Step 3: Build the Frame

1. Install Beams:

  • Use doubled 2x10s or 2x12s for beams, secured to the footings with post brackets.

  • Space beams to support the joists adequately (around 8' apart).

2. Attach Rim Joists:

  • Create the outer frame by securing 2x10s or 2x12s as rim joists to the beams. Use lag screws or bolts for strong connections.

3. Add Joists:

  • Lay 2x8 or 2x10 joists perpendicular to the beams, spaced 16" on center.

  • Use joist hangers to secure the joists to the rim joists and beams.

  • Double-check that all joists are level.

Step 4: Add Blocking for Strength

Install Blocking:

  • Add blocking (short pieces of lumber) between joists to prevent twisting and add rigidity.

  • Place blocking every 4-6 feet along the joists.

Step 5: Install Decking Boards

1. Lay Decking Boards:

  • Start at one edge of the frame and lay pressure-treated or composite decking boards perpendicular to the joists.

  • Leave a 1/8" gap between boards for drainage and expansion.

2. Secure Boards:

  • Use galvanized deck screws to secure each board to the joists.

  • Stagger seams where boards meet for a polished look and structural integrity.

Step 6: Finishing Touches

1. Trim Edges:

  • Use a circular saw to trim overhanging boards for a clean, uniform edge.

2. Seal the Deck:

  • Apply an exterior-grade wood sealant or stain to protect the deck from weathering.

3. Inspect:

  • Check for any loose screws, uneven boards, or structural issues.

Tips for Supporting Significant Weight

  • Use higher-grade lumber (e.g., #1 or #2 grade) for beams and joists.

  • Increase the number of footings and reduce spacing between beams and joists for added strength.

  • Consult a structural engineer or professional contractor if you anticipate extreme loads (e.g., a hot tub or heavy furniture).