12'0_ wide by 12'0_ deep is the most cost-effective size for a deck. The largest deck area that still complies with IRC standards and produces the least amount of material waste. Oct 5, 2021 Most Cost-Effective Deck Size - Decked Out Builders deckedoutbuilders.net https://deckedoutbuilders.net � 2021/10/05 � most-cost-e... deckedoutbuilders.net https://deckedoutbuilders.net � 2021/10/05 � most-cost-e... 12'0_ wide by 12'0_ deep is the most cost-effective size for a deck. The largest deck area that still complies with IRC standards and produces the least amount of material waste. Oct 5, 2021