As combined Sheet pile walls often have the most efficient weight per square foot of wall for load-bearing requirements of over 70 in³/ft (~3,800 cm³/m) the bidder will likely need to purchase, transport and install less steel than with other sheet piling systems. As steel is often priced by weight, a lighter option may often be less expensive in material costs. However, as steel producers know, those who have less efficient options may compensate the tonnage pricing to equalize the square foot / meter of wall costs.

Combined steel sheet piling walls are often quicker and easier to install than heavier z-sheet piles when the sheet piles are over 50 feet (~15 m) in length, due to the fact that only a fraction of the system needs to be driven to full depth under normal project conditions.

There are various types of combined steel walls used by the U.S. Army Corps of Engineers on projects all over the world. The following is a description of the most popular combined sheet piling walls:

• O-sheet piling + Z-sheet piling is built from a steel pipe or pipe sheet pile (pipe with connectors) as primary elements and a pair of intermediate steel sheet piles between as secondary elements combined by connectors. While most countries have a local pipe producing plants, only a handful of markets exist that produce Z or U sheet piles.

• H-sheet piling + Z-sheet piling follows the same configuration as above with wide flange beams or special rolled sections as the primary elements with a form of hooks on the flange tips. The sheet piles are comprised of two flanges having substantially parallel outer faces and an oblique web connected to the two flanges which form a shape similar to the letter Z. The interlocks of a z-sheet pile are positioned beside the wall axis located at the flange ends.

Steel walls with u-shaped sheet piles incorporate steel sheets comprised of a web with two flanges which form a shape similar to the letter U. The interlocks of a single U sheet pile are positioned at both flange ends and are located on the wall axis.

Like Z sheet piles, U sheet piles are best in lighter load or temporary applications.