Massachusetts Ground Snow Load by County and Town

Massachusetts publishes its own table of ground snow loads, Table 1604.11 Snow Loads, Wind Speeds, and Seismic Parameters, 780 CMR Tenth Edition, Chapter 16: Structural Design, through Board of Building Regulations and Standards (780 CMR: Massachusetts Amendments to the International Building Code 2021). twelve of its published figures are set out below with the row each was read from. Only 14 states out of 50 publish anything of their own like it; the other 36 send a reader either to the national code or to a county counter. twelve Massachusetts figures, running from 25 psf at Provincetown to 60 psf at Adams, every one of them quoted from the document it was printed in. Nationally 235 figures were read across 33 states.

Board of Building Regulations and Standards: the state board prints one value per municipality, and the local building department applies it. In its own words: “1608.2 Ground Snow Loads. The ground snow loads to be used in determining the design snow loads for roofs shall be determined in accordance with Table 1604.11.”

The figure is keyed to the county in Massachusetts, as it is in 21 states, so the county line rather than the town line is what changes the answer. The published Massachusetts figures run from 25 psf to 60 psf.

Board of Building Regulations and Standards, Office of Public Safety and Inspections, Division of Occupational Licensure adopts Massachusetts State Building Code, 780 CMR (Tenth Edition), Massachusetts Amendments to the International Building Code 2021 (Tenth Edition). Massachusetts amended it rather than adopting it whole, and 22 states have done the same. The adopting rule reads: “The tenth edition code is based on modified versions of the following 2021 International Codes (I-Codes) as published by the International Code Council (ICC): International Building Code (IBC) International Residential Code (IRC) International Existing Building Code (IEBC) International Mechanical Code (IMC) International Energy Conservation Code (IECC) International Swimming Pool and Spa Code (ISPSC) International Fire Code (IFC)”

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. Board of Building Regulations and Standards works in loads for that reason, and so does every figure set out below.

The Massachusetts document itself is the place to look a town up, and what it prints is applied by Board of Building Regulations and Standards. The document behind it is Table 1604.11 Snow Loads, Wind Speeds, and Seismic Parameters, 780 CMR Tenth Edition, Chapter 16: Structural Design, published by Board of Building Regulations and Standards (780 CMR: Massachusetts Amendments to the International Building Code 2021), read on September 23, 2026. It establishes the point this way: “1604.11 Snow, Wind and Earthquake Design Factors. Ground snow load, pg, basic wind speed, V, and earthquake response accelerations for the maximum considered earthquake, SS and S1, for each city and town in the Commonwealth shall be as given in Table 1604.11.”

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.