Lockport is one of the most historically significant communities in Will County. The city was platted in 1836 as the headquarters of the Illinois and Michigan Canal, and its downtown district — with limestone warehouses, canal structures, and 19th-century commercial buildings — is listed on the National Register of Historic Places. That history gives Lockport a character that’s distinct from the newer subdivisions spreading across the southwest suburbs.
It also means that getting a deck permit in Lockport depends on where your property sits. If your home is in the Historic Preservation District, you’ll face an additional layer of review that doesn’t apply to standard residential properties elsewhere in the city. This guide covers both paths.
The Lockport Building Department
The City of Lockport Building Department is part of the Community and Economic Development Department. It handles plan review, permit issuance, and inspections for all residential and commercial construction, including decks, patios, porches, and accessory structures.
| Detail | Information |
| Department | Building Services (Community & Economic Development) |
| Address | 921 S. State St, Lockport, IL 60441 |
| Building Official | Brian Pohlis |
| Phone | (815) 838-0549, ext. 1135 |
| bpohlis@lockport.org | |
| General Building Line | (815) 838-0549, option 5 |
| Hours | Monday–Friday, 8:00 AM – 4:30 PM |
| Permit Applications | cityoflockport.net/136/Applications |
Permit applications can be submitted in person at the Building Division office or via email. The City also offers over-the-counter permits for simpler projects (HVAC, water heaters, roofing, siding, and windows), but deck permits require full plan review and are not eligible for over-the-counter processing.
When a Permit Is Required
Lockport requires a building permit for any new deck, porch, or patio construction, as well as for alterations or structural modifications to an existing deck. Permits are required to erect, construct, alter, enlarge, or move any structure — including decks, porches, patios, swimming pools, fences, retaining walls, and driveways.
Working without a permit is subject to double the permit fee cost. Homeowners can perform their own work if they are the owner and primary occupant of the single-family residence, but all permits must be obtained before work begins. All contractors working in Lockport must be registered with the Building Department before starting any project.
Standard Residential Deck Permits
For homes outside the Historic Preservation District, the deck permit process follows a straightforward path. You’ll submit your application along with construction plans and a plat of survey, and the Building Department reviews for code compliance.
Here’s what you’ll typically need to include with a standard residential deck application:
- A completed building permit application
- A certified plat of survey showing property lines, easements, and all existing structures
- Dimensioned site plan showing the proposed deck location and distances from property lines
- Framing plan with joist sizes, spacing, beam locations, and span details
- Footing plan showing post locations, footing diameter, and depth (42 inches minimum)
- Ledger board attachment and flashing details
- Elevation drawings showing railing height, stair dimensions, and height above grade
- Material specifications
- Contractor registration information (or homeowner acknowledgment if owner-built)
Standard Illinois building code requirements apply: guardrails required for any deck surface more than 30 inches above grade, minimum guardrail height of 36 inches, baluster spacing no more than 4 inches, stair tread depth of at least 10 inches, and riser height no more than 7.75 inches.
Typical review time for residential deck permits in Lockport is 10 to 14 business days, provided all required information is submitted and the contractor is registered with the City. Once issued, a deck permit is valid for 6 months.
Construction hours per City Code (Ord. §93.131):
- Monday–Friday: 7:00 AM – 8:00 PM
- Saturday: 8:00 AM – 8:00 PM
- Sunday: 8:00 AM – 6:00 PM
Historic District Rules — What’s Different
This is where Lockport diverges from most surrounding communities. If your property falls within the City’s Historic Preservation District, the rules are significantly different — and the standard permit exemptions that apply elsewhere in the city do not apply to your property at all.
The City’s FAQ states this clearly: properties in the Historic Preservation District have special regulations, and the standard list of permit exemptions does not apply to any property in this district. That means even minor exterior work that wouldn’t normally require a permit in standard residential areas may require approval in the historic district.
| Step | Standard Residential | Historic District |
| Building Permit | Yes — Building Dept. | Yes — Building Dept. |
| Certificate of Appropriateness | Not required | Required — H&A Commission |
| Review Body | Building Department only | Building Dept. + H&A Commission |
| Design Scrutiny | Code compliance only | Code + historic compatibility |
| Materials | Must meet structural code | Code + historic architectural standards |
| Permit Exemptions | Some minor repairs exempt | No exemptions — all exterior changes |
| Timeline | 10–14 business days | Longer — depends on H&A schedule |
The Heritage and Architecture Commission (H&A Commission) is a six-member body that reviews all exterior modifications within the Historic Preservation District. For a deck or porch project, you’ll need to obtain a Certificate of Appropriateness from this commission before (or in conjunction with) your building permit.
The H&A Commission evaluates whether your proposed structure is consistent with the historic character of the district. The Lockport Historic District is known for locally quarried limestone construction, and the City’s development code references specific architectural styles found primarily in the downtown area. While this doesn’t mean your deck needs to be made of limestone, it does mean that the design, materials, and placement need to be compatible with the district’s character.
Contact the Planning Department for more information on the Certificate of Appropriateness application process and the commission’s meeting calendar.
Not Sure If You’re in the Historic District?
The Lockport Historic District runs along the Illinois and Michigan Canal through the downtown area. The district includes 59 historic buildings, with the core running parallel to the canal along State Street and the surrounding blocks. If your home is in the downtown or canal-adjacent area, there’s a strong chance you’re in it.
If you’re not sure, contact the Building Department at (815) 838-0549, option 5 or email the Building Official at bpohlis@lockport.org. They can confirm your property’s designation and tell you which approval process applies.
Choosing the Right Materials
For standard residential areas, material choice comes down to performance and preference — pressure-treated lumber, composite, PVC, or hardwood. For historic district properties, your options may be narrowed by what the H&A Commission considers appropriate for the district’s character.
In either case, understanding how different decking materials hold up through Illinois winters is important. Our comparison of heat-resistant composite decking covers how various brands handle sun exposure and freeze-thaw cycles. And for a broader look at where to source materials in the area, our guide to outdoor building supply stores near Bolingbrook is a convenient starting point for Lockport homeowners.
If you’re weighing composite versus wood for a standard residential build, our contractor’s take on choosing the right decking material breaks down the trade-offs between cost, maintenance, and long-term durability.
Build With a Contractor Who Understands the Process
Platinum Decking builds custom decks for homeowners across Lockport — in both standard residential neighborhoods and the historic district. We handle the full permit process, including coordinating with the Heritage and Architecture Commission when required. Call us at (224) 634-4345 to discuss your project.