Missouri Ground Snow Load: Who Sets It

Missouri sets no ground snow load at state level, so every figure comes from a county or city building department. The body to ask is the county commission, or the incorporated city, town or village, where the work is. 19 states work this way, which is why a search for one Missouri figure comes back with several different answers from several different pages, all of them correct for the place they were written for. Missouri publishes ground snow loads through the county commission, or the incorporated city, town or village, where the work is, and the jurisdictions reached for this had put none into a public document at the time they were read.

The county commission, or the incorporated city, town or village, where the work is: the statute lets each community adopt a construction code by reference, and the state adopts none for site built houses. In its own words: “Any community, if the community otherwise has the power under the law to adopt such an ordinance, may adopt or repeal an ordinance which incorporates by reference the provisions of any code or portions of any code, or any amendment thereof, properly identified as to date and source, without setting forth the provisions of such code in full.”

Public Service Commission, Manufactured Housing and Modular Units Program adopts International Building Code-2021 and International Residential Code-2021, adopted by the state for modular units only; site built construction is governed by whatever code the county or the city has adopted, if any (2021 editions). Missouri adopted it as written. The adopting rule reads: “(3) The structure shall be manufactured in accordance with and meet the requirements of the most recently commission-adopted building codes: except as provided in subsections (A) and (B) below, International Building Code-2021; International Plumbing Code-2021; International Mechanical Code-2021; International Residential Code-2021; International Fuel Gas Code-2021; and National Electric Code NFPA 70-2020.”

A ground snow load is a weight per unit area and not a depth, and the two are joined only by the density of the snow on the day, which is why the published documents give the load and leave the depth out. Wet spring snow and dry January snow of the same depth are different weights on the same roof. The county commission, or the incorporated city, town or village, where the work is works in loads for that reason, and so does every figure set out below.

A Missouri figure for an address the documents below do not cover comes from the county commission, or the incorporated city, town or village, where the work is. The document behind it is RSMo Section 64.170, County commissions control construction, issue building permits, published by Missouri Revisor of Statutes, read on September 23, 2026. It establishes the point this way: “For the purpose of promoting the public safety, health and general welfare, to protect life and property and to prevent the construction of fire hazardous buildings, the county commission in all counties of the first and second classification, as provided by law, is for this purpose empowered, subject to the provisions of subsections 2 and 3 of this section, to adopt by order or ordinance regulations to control the construction, reconstruction, alteration or repair of any building or structure”

14 of 50: Connecticut, Indiana, Maryland, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New Jersey, North Carolina, Rhode Island, Utah, Vermont, Wisconsin. The other 36 split into 17 that adopt the national code without a snow amendment and 19 that leave every figure to a county or city building department. That is the single most useful fact about this subject and no one state's own website carries it.