Most sheet construction materials, such as plywood, composition board, paneling and drywall are sold in sheets that are 4 feet (or some multiple of 4) by 8 feet (or some other multiple of 4). For example, plywood is often sold in 4 x 8 sheets. By designing your room with dimensions that are multiples of 4 you will reduce the waste of materials and reduce the amount of cutting that must be done to install sheet materials. Reducing the cutting reduces labor costs and saves time. Instead of building a room that is 13 by 15 feet, design it to be 12 x 16 feet to save on sheet materials and labor costs.

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