City of Decatur Building Inspections Division

City of Decatur, Illinois

city

One Gary K. Anderson Plaza, 3rd Floor, Decatur, IL 62523

Required

Required

The City's own codified Chapter 67.2, Residential Building Code (read in full, all 18 numbered sections), adopts the 2021 International Residential Code by reference, "the same being found and declared by the Council to be regulations as defined by applicable statute," as amended by Ordinance 2023-94 (December 18, 2023, effective January 1, 2024) and Ordinance 2018-65 (November 5, 2018, effective January 1, 2019). The Chapter deletes R103.2, R105.2 Building item #2, R112, and R302.1 Exceptions 2, 3 and 4; amends R105.2 Building item #1 (accessory-structure exemption reduced from 200 to 120 square feet), R105.5, Table R301.2, and R313.2 (residential sprinkler requirement changed from "shall" to "may"); and adopts a named list of IRC appendices. None of the deletions or amendments touches Chapter 8 (roof-ceiling construction) or Chapter 9 (roof assemblies), so those chapters apply as published in the base 2021 IRC.

Required About drip edge

Required — Enacted by the City itself. Chapter 67.2, Section 8(c) amends Table R301.2 to add, verbatim, "Ice Barrier underlayment required, yes," alongside the other climatic and geographic design criteria the City filled in for its jurisdiction. About ice & water barrier

Not required — Chapter 67.2, read in full, adds no impact-resistance requirement to Table R301.2 or elsewhere: the City's own added table values cover ground snow load, wind design speed, seismic design category, weathering, frost line depth, termite, ice barrier, flood hazards, air freezing index and mean annual temperature, with no UL 2218, Class 4, Class IV or hail-exposure entry among them.

NO DOLLAR OR SQUARE-FOOTAGE THRESHOLD APPLIES TO ROOF WORK. Chapter 67.2's own list of deletions and amendments to R105.2 (Work exempt from permit) touches only the one-story detached accessory structure exemption (reduced to 120 square feet) and deletes the fence exemption; it adds no exemption reaching roof covering, repair or replacement, so a permit is required regardless of project value. The City's own Permit Fee Schedule (dated 02/2020) sets the general fee for one- and two-family residential permits, which is what a roofing permit falls under, at 0.5% of project value with a minimum of $50; there is no separate roofing fee line or minimum-value carve-out.

Enacted by the City itself. Chapter 67.2, Section 8(c) amends Table R301.2 to add, verbatim, "Wind-Design Speed 107 MPH," alongside Ground Snow Load 20 PSF, Seismic Design Category B, Weathering Severe, Frost Line Depth 36 inches, Termite moderate to heavy, and Flood Hazards 8/1/79. The ordinance does not state whether the 107 MPH figure is a nominal (ASD) or ultimate design wind speed basis.

Chapter 67.2 adopts the 2021 IRC and its read-in-full amendment list (Section 7 deletions; Section 8 amendments) touches neither Chapter 9 nor any roof-recover provision, so the base 2021 IRC governs. 2021 IRC R908.3.1.1, Roof recover not allowed, bars a roof recover under three conditions, the third being "where the existing roof has two or more applications of any type of roof covering." A roof with two or more existing layers must be torn off before recovering; up to one existing layer may be recovered.

Chapter 67.2 adopts the 2021 IRC and its read-in-full amendment list does not touch Chapter 8 (roof-ceiling construction), so the base 2021 IRC roof sheathing provisions (IRC Chapter 8) apply unmodified, with no Illinois state amendment to point to (Illinois has adopted no residential building code of its own).

ILLINOIS TAXES THE ROOFER, NOT THE JOB, AND THE OPERATIVE RATE IS NOT KEYED TO THE JOB ADDRESS. Under 86 Ill. Adm. Code 130.1940(c), a construction contractor "does not incur Retailers' Occupation Tax liability as to receipts from labor furnished and tangible personal property ... incorporated into a structure," but "incurs Use Tax on the cost price of the tangible personal property that is incorporated into real estate," with "roofing materials" named in the rule's own list of examples. Repair and replacement are taxed identically: 86 Ill. Adm. Code 130.1940(a)(3) defines "construct" to include "repair, renovate or remodel." The state rate has been 6.25% since January 1, 1990 (86 Ill. Adm. Code 130.101(c)(1)). The combined rate that actually lands on materials is the rate where the supplier's counter or the contractor's own place of business is located, not a rate keyed to the Decatur job address (86 Ill. Adm. Code 130.2075(b)(3)). A third-party aggregator (Avalara) currently quotes a combined Decatur, IL rate of 9.25% (6.25% state, 1.5% Macon County, 1.5% City), which this record reports only as an example figure; the authoritative lookup is the Illinois Department of Revenue's own MyTax Illinois Tax Rate Finder.