Downers Grove requires a building permit for all new decks, porches, and gazebos — and for any structural modifications to an existing deck. The Village’s Community Development Department handles the process through an online permit portal, with a dedicated “Deck” application type that streamlines the submittal. If you’re planning a deck project, this guide covers what you’ll need, how long it takes, and the zoning rules that apply.

The Community Development Department

The Village of Downers Grove Community Development Department oversees all building permits, plan reviews, inspections, and code compliance. The department is located at Village Hall and handles both the planning (zoning) and building (code compliance) sides of the process.

DetailInformation
DepartmentCommunity Development
Address801 Burlington Ave, Downers Grove, IL 60515
Phone(630) 434-5515
Permit Portaldowners.us/permits
Permit Formsdowners.us/permit-forms-and-docs
Building CodeInternational Residential Code with DG amendments
Municipal Codedownersgrove.municipalcodeonline.com

The Village’s advice is straightforward: call Community Development at (630) 434-5515 before starting any interior or exterior property improvements to confirm what permits are needed.

How to Apply for a Deck Permit

Downers Grove uses an online permit portal with a specific “Deck” application type. Here’s the step-by-step process:

  1. Create an account on the Village permit portal or log in to your existing account
  2. Select “Apply for a Building or Fire Permit” under the Building and Fire section
  3. Choose “Deck” as the application type, select the nature of work, and describe the project
  4. Select all relevant work items (structural framing, electrical, etc.)
  5. Enter your property address — the system will locate it within the Village’s records
  6. Upload required documents including owner authorization form, contractor list, plans, and plat of survey
  7. Submit the application

What to Submit

Your deck permit application will need to include:

  • A completed permit application through the online portal
  • Owner authorization form (required for all permits)
  • A list of contractors working on the project
  • A plat of survey showing property lines, easements, and all existing structures
  • Dimensioned site plan showing the proposed deck location and distances from all property lines
  • Construction drawings: framing plan, footing plan, ledger board details, and elevation drawings
  • Material specifications

Only homeowners or licensed contractors can pull permits in Downers Grove.

Zoning Setbacks for Decks

Setbacks vary by zoning district:

Zoning DistrictSide SetbackRear Setback
R-45 feet5 feet
All other residential6 feet6 feet

In PUDs or subdivisions with 10+ lots containing permanent common open space under recorded covenants or a public park, patios and decks may be placed as close as 1 foot from the rear and side lot lines. Confirm with Community Development whether your lot qualifies.

No deck may be built within an easement. Combined footprint of all structures cannot exceed 32% of lot area. Use the Village’s Parcel Navigator or call (630) 434-5515 to confirm your zoning.

Code Requirements

Downers Grove follows the IRC with local amendments. Key requirements for residential decks:

  • Footing depth of at least 42 inches (DuPage County frost line)
  • Guardrails required for any deck surface more than 30 inches above grade
  • Minimum guardrail height of 36 inches; baluster spacing no greater than 4 inches
  • Ledger boards attached with approved fasteners; joist hangers at all connections
  • Stair tread depth at least 10 inches, riser height no more than 7.75 inches

Review Timeline and Project Manager

Once your application is received, the Village assigns a Project Manager as your primary contact. First review takes approximately 10 business days. If revisions are needed, the Village asks for responses within 5 business days.

Construction Hours

Monday–Saturday: 7:00 AM – 7:00 PM. No construction permitted on Sunday. This is more restrictive than some neighboring communities, so plan accordingly.

Inspections

After your permit is approved and fees are paid, the Village issues a Permit Card (must be displayed on-site) and a Permit Inspection Card. Approved drawings must be kept on-site. Standard deck inspections include footing, framing, and final. Call (630) 434-5515 to schedule.

Choosing the Right Materials

If you’re comparing composite versus pressure-treated lumber, our review of heat-resistant composite decking (platinumdecking.com/heat-resistant-composite-decking/) covers how different products handle DuPage County’s climate. For help choosing colors, see our guide to picking the right deck color. And for a contractor’s perspective on material trade-offs, our breakdown of how to select the right decking material covers cost, maintenance, and durability.

Ready to Start Your Project?

Platinum Decking designs and builds custom decks for homeowners in Downers Grove and across the western suburbs. We handle the full permit process — from plan preparation through the Village portal submission and all required inspections. Call us at (224) 634-4345 to discuss your project.