Construction of the "North Carolina" class was slowed by the aforementioned material issues, the changes made to the basic design after this date—namely the substitution of 16-inch for 14-inch guns—and the need to add both length and strength to the slipways already present in the navy yards. Increased use of welding was proposed as a possible way to reduce weight and bolster the structural design, as it could have reduced the ships' structural weight by 10%, but it was used in only about 30% of the ship. The costs associated with welding and an increase in the time of construction made it impractical.