How much would it cost to build a 12x24 deck?
12x24 (288) 288. $11,520-$17,280. 16x20 (320) 320. $12,800-$19,200. Click to see full answer. Also know, how much does it cost to build a 20x20 deck? The average homeowner spends $2,200 to build a 10x10 foot deck, $6,160 to build a 14x20 deck, and $8,800 to build a 20x20 deck.