Calculate deck materials, posts, and hardware
A deck calculator estimates lumber, hardware, and materials for building a deck. Accurate planning ensures you have everything needed before starting construction.
Decking Boards = (Deck Area / Board Width) × 1.1 waste factor
16" on center: Standard for residential decks, supports most decking. 12" on center: Required for diagonal decking and some composites. 24" on center: Only for 2× decking on low-traffic areas.
Calculate deck area, divide by board coverage, add 10-15% waste. For diagonal patterns, add 20%. Order extra boards to match weathering for future repairs.
Roughly 350 screws per 100 sq ft of decking (2 per joist intersection). Hidden fastener systems: approximately 90 clips per 100 sq ft. Buy extra for mistakes.
Posts: 4×4 for low decks, 6×6 for higher decks. Beams: Typically doubled 2×8, 2×10, or 2×12 depending on span. Check local code requirements and span tables.
Typical footing: 18" diameter × 42" deep (below frost line). Uses about 3 cubic feet of concrete. Pre-mix bags: Two 80 lb bags per footing. Adjust for local frost depth requirements.
Pressure-treated wood: Affordable, requires annual maintenance, 15-20 year lifespan. Composite: Higher cost, minimal maintenance, 25-30+ year lifespan, won't splinter.