Town of Collierville, Tennessee - Building and Codes Division

Town of Collierville, Shelby County, Tennessee

city

Collierville, TN

Required

Required

The Building and Codes Division lists the adopted codes as the 2018 International Building Code, 2018 International Residential Code, 2018 International Plumbing Code, 2018 International Mechanical Code, 2018 International Fuel Gas Code, 2017 National Electrical Code, 2018 International Property Maintenance Code, 2018 International Swimming Pool and Spa Code, 2018 International Existing Building Code, 2018 International Energy Conservation Code and 2018 International Fire Code, each with local amendments. The amendments are enacted by Ordinance 2020-06, which the Town publishes in full and which sets out the residential modifications at section 150.070. Tennessee sets a statewide minimum of the 2018 International Residential Code for one- and two-family dwellings, so Collierville sits exactly at the state floor rather than above it.

Not required — Collierville imposes no impact-resistance or hail-rating requirement on roof coverings. Ordinance 2020-06, which carries the town's entire set of local amendments across every adopted code, was read in full and contains no reference to UL 2218, to FM 4473, or to a Class 4 or Class IV impact classification. TO DISAMBIGUATE ONE PHRASE THAT LOOKS RELEVANT AND IS NOT: the ordinance does use the word impact once, in an energy-code table footnote setting a maximum U-factor "for impact rated fenestration complying with Section R301.2.1.2." That is a windborne-debris rating for WINDOWS, established under a different standard, and it says nothing about the hail resistance of a roof covering. Impact resistance for roof coverings is established by UL 2218 or FM 4473 and neither appears here.

There is no dollar threshold and no square-footage threshold for roofing in Collierville, and the reason is that the town has cut its permit-exemption list down to a single item. Ordinance 2020-06, in the residential amendments at section 150.070, deletes exemptions 1 through 4 under section R105.2 "Work exempt from permit" in the Building category and amends number 5, so that the first five items now read "Reserved, Reserved, Reserved, Reserved, Sidewalks and driveways on private property not more than 30 inches above adjacent grade." The same ordinance amends section R105.1 to require a permit of "any owner or authorized agent who intends to construct, enlarge, alter, repair, move, demolish or change the occupancy of a building or structure" - the word repair is in the operative list. Roofing appears nowhere in the exemptions that survive, so roofing work sits on the permit side of the line. Note one further local requirement that reaches roof work even though it is not about the covering: the town's alternative structural compliance method at section R301.2.2.3.8.7 requires that "roof framing members shall be attached to wall top plates with 18 gauge galvanized steel clips (ex. RT7A or H2.5A) or equivalent spaced not more than 4 feet on center," in addition to the fastening required by Table R602.3(1).

Two layers maximum - one overlay is permitted, and a second existing layer requires a tear-off. Collierville adopts the 2018 International Residential Code at section 150.070 of Ordinance 2020-06, and the whole of that ordinance was read - twenty-nine pages covering the building, plumbing, mechanical, residential, energy, fire and property maintenance amendments. It contains no amendment to section R908 or to any part of the roof assemblies chapter, so the adopted code text governs unchanged. Section R908.3.1.1 of the 2018 International Residential Code provides that a roof recover shall not be permitted where any of three conditions occur, the third being "where the existing roof has two or more applications of any type of roof covering." One existing layer may be recovered; a second forces removal. The other two conditions apply whatever the layer count: a covering that is water soaked or has deteriorated to the point that it is not an adequate base for additional roofing, and a covering of slate, clay, cement or asbestos-cement tile. TENNESSEE PUTS A FLOOR UNDER THIS THAT IS WORTH KNOWING: the statewide minimum for one- and two-family dwellings is the 2018 International Residential Code, and Tenn. Comp. R. & Regs. 0780-02-23-.12(2) provides that "no city, county, town, municipal corporation, metropolitan government, or political subdivision of the State of Tennessee shall adopt or enforce any ordinance prescribing less stringent standards ... than those established hereunder" without the state fire marshal's written approval. A Tennessee jurisdiction may therefore be stricter than the two-layer rule but cannot be more permissive than it.

9.75% in the Town of Collierville - the 7% Tennessee state sales tax plus the 2.75% local tax levied by the town. Tennessee sets the state rate and lets each county or incorporated city levy its own local tax on top: the Department of Revenue states that "any county or incorporated city, by resolution or ordinance, may levy the local sales and use tax on the same privileges that are subject to the state's sales or use tax," and that "the local tax rate may not be higher than 2.75% and must be a multiple of .25." THAT CAP IS WHY A CITY RATE IS NOT ADDED TO ITS COUNTY RATE: several Tennessee cities levy the full 2.75% while sitting in a county that levies less, and stacking the two would exceed the statutory maximum. Where an incorporated city has its own rate, that rate is the local rate inside the city; where it has none, the county rate applies. The figures here are from the Department of Revenue's own machine-readable rate file for the third quarter of 2026, which the Department publishes for use in tax calculation applications. COLLIERVILLE IS THE CASE THAT SHOWS WHY THE CITY RATE MATTERS. Shelby County levies 2.25%, but the Town of Collierville levies the full 2.75% permitted by statute, and the town rate applies inside the town. A job in Collierville is therefore half a point higher on tax than one elsewhere in Shelby County, and using the county figure would understate it.