How Nelson's all-forward layout saved weight

The selected Nelson layout used far less machinery space than the faster alternatives and concentrated all three main turrets forward. Designers placed the engine rooms ahead of the boiler rooms to keep furnace heat away from the magazines, accepting longer propeller shafts. The ships still received 16-inch/45 rather than 16-inch/50 guns even though the completed design remained below the treaty ceiling. The raised middle turret could theoretically train far aft, but its blast would damage the bridge, flag bridge, and flying bridge at the extreme angle. Raising the after turret instead might have allowed the 6-inch secondary battery to move forward with better spacing and firing arcs. The arrangement packed heavy protection and firepower into a compact hull, with costs the constructors understood.