Deck Permit in Cook County, Illinois
Permit required
Yes, a permit is required
Before constructing, altering or replacing a deck at a property in unincorporated Cook County.
Issued byCook County Department of Building and Zoning
By Mario Bailey, verified against official sources
Quick answer
Decks are listed by name in the Cook County Building Code among the structures that may not be erected, constructed, altered, relocated or demolished without first obtaining a permit, and the code provides no size or height exemption for them. The department's deck flyer requires a plat of survey less than five years old with the deck drawn on it, plus detailed construction drawings covering joist and beam sizes, post footings, guardrails, balusters and stairs. Decks that encroach into a rear or side yard setback may also require a zoning variance.
Who is pulling this permit?
Apply yourself
Hire it out
Sponsored
If a contractor builds your deck, they usually handle the permit as part of the job. Compare a few bids before you commit.
Compare deck contractor quotes on Angi
Sponsored link. PermitNotebook may earn a fee if you request quotes through it. Partners never influence our permit data.
When a permit is usually needed
Before constructing, altering or replacing a deck at a property in unincorporated Cook County.
What a deck permit costs in Cook County
How to apply in Cook County
In Cook County, a residential deck permit application is a set of construction documents that show what will be built and prove it meets the IRC deck provisions. In practice that means a scaled site plan locating the deck and its setbacks, plus deck plans and structural details covering the footings, posts, beams, joists, ledger, guards, and stairs.
What most deck permit applications include:
- For Cook County, a permit application identifying the work, the deck's size (square footage), and whether electrical work such as lights or receptacles is included, submitted for plan review before construction begins (IRC R106).
- For Cook County, a scaled site plan (for example 1/4 inch to 1 foot) showing the new deck's location relative to the house, its overall length and width, and dimensioned distances from the deck to all property lines and other structures so required setbacks can be verified (IRC R106.1.1).
- For Cook County, a deck plan drawn to scale showing overall dimensions and the framing layout: joist size, spacing, span, and species; beam size and span; post size and height; and footing or pier size and depth (IRC R507.4 posts, R507.5 beams, R507.6 joists, R507.3 footings).
- For Cook County, a section or side elevation with connection details showing the ledger attachment to the house band joist with flashing, the fastener or bolt schedule, joist hangers, post-to-beam and post-to-footing connections, and the required lateral load connection (IRC R507.9 ledger connection, R507.9.2 lateral connection, R507.2.4 flashing).
- Footing sizing derived from tributary area, the soil bearing value, and design loads per IRC Table R507.3.1, with footings shown bearing on undisturbed soil at the frost depth required by the jurisdiction (IRC R507.3).
- Details for the guards required where the walking surface is more than 30 inches above grade, and for the stairs and handrails, showing guard height and opening limits, stair riser and tread dimensions, and handrail location (IRC R312 guards, R311.7 stairs and handrails).
- For designs that fall outside the prescriptive R507 tables (for example multi-story or stacked decks, or a ledger attached to a cantilever), engineered and stamped structural plans are submitted in place of the prescriptive details (IRC R507.1 and R301).
General submittal guidance from IRC R106.1.1 (construction documents) and IRC R507 (exterior decks), 2021 IRC. Source. Cook County Department of Building and Zoning sets the exact checklist for Cook County.
Where to apply in Cook County:
Cook County Department of Building and Zoning
- Cook County Department of Building and Zoning, 69 W. Washington St., Suite 2830, Chicago, IL 60602
- Phone: 312-603-0500
- Email: intake.bnz@cookcountyil.gov
Deck Permit in Cook County compared with nearby Illinois localities
| Locality | Permit needed? | Threshold | What each Illinois schedule says | Verified |
|---|---|---|---|---|
| Cook County | Permit required | Any size | ..."A. Minimum Fee (except uses of land not involving buildings) 73.50 plus $18.50 for... | |
| Chicago | Permit required | Any size | Installation or alteration of a deck is $250 per dwelling unit served under the 2026... |
Inspections and closing out your permit
In Cook County, deck work is inspected in sequence as it is built: the footings before concrete is placed, the framing before the decking boards go down, and a final inspection once the deck is complete. Each stage checks the items that would be hidden or unsafe if missed.
- Footing or pier inspection in Cook County: after the holes are dug and any forms or reinforcing are set but before concrete is placed, the inspector checks footing depth and diameter, a flat undisturbed bearing surface, and that the holes are free of water (IRC R109.1.1 foundation inspection; R507.3 footings).
- Framing inspection in Cook County: after the deck is framed but before the decking conceals it, the inspector verifies the ledger attachment and its flashing, the fastener and bolt schedule, joist hangers and metal connectors, post-to-beam and post-to-footing connections, and the lateral load connection; call it before decking is installed (IRC R109.1.4 frame inspection; R507.9 ledger and flashing).
- Final inspection in Cook County: after the deck is complete and before it is used, the inspector confirms guard height and opening limits (a 4 inch sphere must not pass, 4 3/8 inch at stairs), stair riser and tread dimensions, handrail height and graspability where there are 4 or more risers, stair landings, and required stair lighting (IRC R109.1.6 final inspection; R312 guards, R311.7 stairs and handrails).
Schedule each inspection in advance and pass the final before you use the work or close the permit. Request inspections through the Cook County permit portal or by phone at 312-603-0500.
Inspection sequence from IRC R109 (inspections: R109.1.1 footing before concrete, R109.1.4 frame, R109.1.6 final), 2021 IRC. Source. An open permit left un-inspected can surface later in a title search or home sale.
Your Deck Permit checklist for Cook County
- Confirm the requirement. Yes, a permit is required. Usually needed: Before constructing, altering or replacing a deck at a property in unincorporated Cook County.
- Budget the fee. Cook County Code of Ordinances Sec. 32-1, Building Permit Fee Schedule, item 3-B ALTERATIONS, REMODELING AND MISCELLANEOUS ITEMS OF CONSTRUCTION: "A. Minimum Fee (except uses of land not involving buildings) 73.50 plus $18.50 for each additional $1,000.00 of estimated cost in excess of $5,000.00." The estimated cost is based on the signed contracts between the owner and all contractors. A $100.00 residential deposit is payable online and deducted from the final permit fee. Fee schedule codified through Ord. No. 25-2843, enacted June 12, 2025. Official fee schedule.
- Apply. In Cook County, a residential deck permit application is a set of construction documents that show what will be built and prove it meets the IRC deck provisions. In practice that means a scaled site plan locating the deck and its setbacks, plus deck plans and structural details covering the footings, posts, beams, joists, ledger, guards, and stairs. Start at the Cook County permit portal.
- Keep the office details handy. Cook County Department of Building and Zoning. Phone: 312-603-0500. Address: Cook County Department of Building and Zoning, 69 W. Washington St., Suite 2830, Chicago, IL 60602.
- Plan for inspections. In Cook County, deck work is inspected in sequence as it is built: the footings before concrete is placed, the framing before the decking boards go down, and a final inspection once the deck is complete. Each stage checks the items that would be hidden or unsafe if missed.
Compiled from the official sources on this page. Last checked .
Frequently asked questions
- Do you need a deck permit in Cook County?
- Decks are listed by name in the Cook County Building Code among the structures that may not be erected, constructed, altered, relocated or demolished without first obtaining a permit, and the code provides no size or height exemption for them. The department's deck flyer requires a plat of survey less than five years old with the deck drawn on it, plus detailed construction drawings covering joist and beam sizes, post footings, guardrails, balusters and stairs. Decks that encroach into a rear or side yard setback may also require a zoning variance. Always confirm with the Cook County Department of Building and Zoning before starting.
- How much does a deck permit cost in Cook County?
- Cook County Code of Ordinances Sec. 32-1, Building Permit Fee Schedule, item 3-B ALTERATIONS, REMODELING AND MISCELLANEOUS ITEMS OF CONSTRUCTION: "A. Minimum Fee (except uses of land not involving buildings) 73.50 plus $18.50 for each additional $1,000.00 of estimated cost in excess of $5,000.00." The estimated cost is based on the signed contracts between the owner and all contractors. A $100.00 residential deposit is payable online and deducted from the final permit fee. Fee schedule codified through Ord. No. 25-2843, enacted June 12, 2025. See the official fee schedule for current amounts.
- Where do you apply for a deck permit in Cook County?
- You can apply through the Cook County permit portal or contact the Cook County Department of Building and Zoning directly. The links are listed on this page.
- Can a homeowner pull a deck permit themselves in Cook County?
- Under Illinois law (225 ILCS 320/3): Whether an owner can pull a building permit is a municipal question in Illinois; there is no state building-permit statute. At the state level, the Plumbing License Law requires that 'all plumbing shall be performed only by plumbers licensed under the provisions of this Act,' but exempts owner-occupants (and lessee-occupants) of single-family residences doing their own plumbing, provided the work meets Illinois State Plumbing Code minimum standards, is submitted for inspection by the Department or local unit, uses no unlicensed helpers ('shall not employ other than a plumber licensed pursuant to this Act to assist'), and the occupant has 'a current intention to live in such premises as his or her bona fide sole and exclusive residence for a period of not less than 6 months after the completion of the plumbing work.' Confirm how Cook County applies this before you apply.
From the Library
What else needs a permit in Cook County
Every other permit type we have verified for this jurisdiction, with the rule that applies here.
| Project | Permit needed? | Threshold | Typical fee |
|---|---|---|---|
| Electrical Permit | Permit required | Any size | ...Permit Fee Schedule, item 1-E SINGLE-FAMILY DWELLINGS: 0 to 499 square feet... |
| Fence Permit | Permit required | Any size | ...Building Permit Fee Schedule, item 10-B FENCES: "Minimum Fee 100.00 Plus $2.00 for... |
| HVAC Permit | Permit required | Any size | ...item 2-M.C "Single-family dwelling air conditioning, minimum to 3½ tons and $21.00... |
| Patio Permit | Permit required | Any size | ..."A. Minimum Fee (except uses of land not involving buildings) 73.50 plus $18.50 for... |
| Plumbing Permit | Permit required | Any size | ...Plumbing Permit Fee Schedule, item 3-P PLUMBING: "A. Minimum Fee 143.60 plus $20.00... |
| Pool Permit | It depends | prefabricated above-ground pools accessory to detached single-family dwellings | ...Permit Fee Schedule, item 16-B MISCELLANEOUS FEES, Swimming Pool, minimum $105.00... |
| Roof Replacement Permit | Permit required | Any size | ...Schedule, item 13-B ROOF RECOATING OR COVERING: Residential, Single-Family... |
| Shed Permit | It depends | prefabricated storage containers | ...Permit Fee Schedule, item 2-B PRIVATE GARAGES - SHEDS: "Minimum Fee 73.50 or $21.00... |
| Solar Permit | Permit required | Any size | ...flyer: "The average minimum permit fee for any installation is... |
Deck Permit in other Illinois localities
Everything above, sourced
Code references
National and state model-code sections the general guidance on this page is drawn from. They are not Cook County documents; the office above sets the local rules.
How this deck permit page for Cook County was verified. 2 official sources: cookcountyil.gov, library.municode.com; fee schedule: official document. Last checked by Mario Bailey, not confirmed with Cook County Department of Building and Zoning. Rules change; confirm before you build. How we verify.
Last checked: Report an error on this page