High for basic planting and landscaping; Moderate for projects involving new irrigation systems, low-voltage lighting, or retaining walls, which may require professional design, installation, and permits.
Basic perennial garden installation, excluding significant structural additions or complex utility extensions, is considered low complexity from a code and permitting perspective in DuPage County.
Project Guidelines & Rules
General Project Requirements & Permitting
3 Rules
Obtain necessary permits prior to commencing work, especially if involving significant grading, structural elements (e.g., retaining walls over 48 inches), new electrical circuits, or plumbing connections.
Your local municipality's building department requirements (IRC Section A105.1 and local ordinances)
Ensure all proposed work adheres to established property line setbacks and zoning ordinances.
Your local municipality's zoning ordinances
Contact J.U.L.I.E. (Joint Utility Locating Information for Excavators) at 811 at least 3 business days prior to any excavation.
Illinois Underground Utility Facilities Damage Prevention Act
Site Preparation, Grading, and Drainage
3 Rules
Site grading must ensure positive drainage of surface water away from existing foundation walls and adjacent structures.
2024 IRC Section R401.3
Installation of retaining walls exceeding 48 inches (1219 mm) in height (measured from the bottom of the footing to the top of the wall) or subject to unusual loading conditions shall be designed by a licensed professional engineer.
2024 IRC Section R404.1.3.1
Any permanent structures that bear load and are susceptible to frost heave (e.g., large raised planters with foundations, structural retaining walls) must have foundations extended to a minimum depth below the frost line.
2024 IRC Section R403.1.4.1 (DuPage County minimum 42 inches below final grade)
Electrical Installations (Landscape Lighting & Outlets)
4 Rules
All underground wiring for landscape lighting or outdoor receptacles shall be installed at the appropriate burial depths and protected against physical damage as per code.
2023 NEC Article 300.5 (e.g., UF cable 12 inches for 120V residential circuits, 6 inches if GFCI protected and 20A or less)
All 120V outdoor receptacles shall be listed as weather-resistant (WR) type and provided with ground-fault circuit-interrupter (GFCI) protection.
2023 NEC Sections 210.8(A)(3) and 406.9(B)
Low-voltage landscape lighting systems (systems operating at 30 volts or less) must comply with specific wiring methods and protection requirements.
2023 NEC Article 411
All electrical work shall be performed by a licensed electrician and inspected by the local building department.
Your local municipality's licensing and inspection requirements (referencing 2023 NEC)
Plumbing Installations (Irrigation Systems)
3 Rules
Any connection of an irrigation system to a potable water supply shall be equipped with an approved backflow prevention device to protect the public water system from contamination.
Illinois Plumbing Code Section 608.16.5
All exterior water lines or irrigation piping exposed to freezing temperatures shall be adequately protected from freezing by insulation, heat, or proper drainage/winterization procedures.
Illinois Plumbing Code Section 305.4
Installation, repair, or maintenance of any irrigation system connected to a potable water supply must be performed by a licensed plumber.
Illinois Plumbing Code (general licensing requirements enforced by local municipalities)
