Bolingbrook, IL Fence Regulations: Retaining Walls (2026)

Section 30-179 of the Bolingbrook Code of Ordinances splits retaining wall requirements by height. Under subsection (a), any retaining wall built greater than four feet in height must be designed by a structural engineer licensed by the State of Illinois, meaning stamped engineering plans are required before construction on taller walls. Under subsection (b), a retaining wall greater than two feet but no more than four feet in height does not need a licensed engineer's design but does require a permit from the village engineer, and the wall must be built either to the village's own standard detail or to an approved manufacturer's specification for the product being used, such as a segmental block system.

Read together, the ordinance creates three practical tiers: walls of two feet or less fall outside this section's permit and design triggers, walls over two feet up to four feet need a village engineer permit and standard or manufacturer-approved construction, and walls over four feet need both a permit and a state-licensed structural engineer's design. The section sits in Chapter 30, Article III, the village's subdivision and land development design standards, so it applies to retaining walls built as part of a development, grading plan or lot improvement reviewed by the village engineer rather than existing walls installed before these standards took effect. The section carries an illustrative retaining wall diagram in the code showing the measurement convention used to determine wall height for these thresholds.