Deck Calculator

Estimate materials for a simple rectangular deck (decking, joists, beams, posts).

Note: This provides basic estimates. Always consult local building codes and consider specific load requirements, footing details, hardware, and railing needs.

Deck Dimensions (Feet)

Deck Length (parallel to house/beams):

Deck Width (joist span direction):

Decking Boards

Actual Board Width (inches):

Gap Between Boards (inches): Typically 1/8" (0.125) or 3/16" (0.1875).

Decking Waste Overage (%): Typically 10-15% for cuts and waste.

Framing (Joists, Beams, Posts)

Joist Spacing - On Center (inches): Common is 16 inches on center (OC). Check local codes.

Beam Spacing / Max Joist Span (feet): Distance between beams, or max unsupported joist length. Depends on joist size/grade. Consult span tables.

Post Spacing Along Beams (feet): Distance between support posts under each beam. Depends on beam size/load. Consult span tables.