The ice barrier rule is the requirement most often left off a Minnesota roof estimate, and it is the one most likely to matter when the January thaw starts. Here is the adopted code text, what it means on your roof, and who pays for it on a claim.
Minnesota requires an ice barrier running from the eave to a point at least 24 inches inside your exterior wall line — measured inside the wall, not from the gutter. On roofs 8:12 and steeper it also has to run at least 36 inches up the slope. If a quote does not say how far the ice barrier runs, that quote is not comparable to one that does.
Yes, in areas with a history of ice forming along the eaves and backing water up under the roofing — which is effectively the entire state.
The requirement is specific about both material and coverage. Material: not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet used in place of normal underlayment. Coverage: from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building.
The phrase that gets misread is “inside the exterior wall line.” The 24 inches is measured from the plane of your exterior wall going up the roof — not 24 inches from the edge of the roof. On a house with a deep soffit overhang, correctly installed ice barrier is meaningfully wider than a single three-foot course.
2020 Minnesota Residential Code, R905.1.2 (and Minnesota Building Code 1507.1.2): the ice barrier “shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building.” Source: Minnesota Residential Code R905.1.2
Yes. On roofs with a slope of 8:12 or greater, the ice barrier also has to be applied not less than 36 inches measured along the roof slope from the eave edge.
Steeper roofs shed faster, but the eave still sits over unheated overhang and still forms ice. The steep-slope provision sets a floor measured along the slope, so on a steep roof you are working to both requirements.
2020 Minnesota Residential Code, R905.1.2: for roofs with slope 8:12 or greater, “the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building.” Source: Minnesota Residential Code R905.1.2
Not if it is unconditioned. The code exempts detached accessory structures that do not contain conditioned floor area.
A detached garage you have finished and heated is a different situation — once there is conditioned floor area, the exemption stops applying.
2020 Minnesota Residential Code, R905.1.2, exception: “Detached accessory structures not containing conditioned floor area” are exempt. Source: Minnesota Residential Code R905.1.2
If you carry replacement cost coverage, Minnesota law requires that coverage to pay for repair to the minimum code required by state or local authorities — subject to your policy limits.
This is the practical reason the code section above is worth reading. An older roof may have had a single narrow course of ice barrier, or none. When it is replaced, the new roof must meet current code, and code-upgrade coverage is the mechanism that pays for the difference.
For a partial loss, the statute extends to the damaged portion of the property unless your policy provides broader coverage. Read the declarations page.
Minn. Stat. § 65A.10, subd. 1: where replacement cost insurance is offered, “the insurance must cover the cost of replacing, rebuilding, or repairing any loss or damaged property in accordance with the minimum code as required by state or local authorities,” subject to applicable policy limits. Source: Minn. Stat. § 65A.10
Look for three things in writing: the material, how far it runs, and whether the valleys are included.
A quote that says “ice and water shield” with no dimension is not telling you what you are buying. A quote that says the barrier runs from the eave to at least 24 inches inside the exterior wall line — and 36 inches along the slope where the pitch is 8:12 or steeper — is describing code-compliant work you can compare against another bid.
This is the most common place two Minnesota roof quotes quietly differ in price. One is meeting code and one is meeting the eave.
This page quotes Minnesota statutes and the adopted Minnesota building code and links to the official text of each so you can read it yourself. It is general information from a licensed contractor, not legal advice, and it is not a substitute for reading your own policy. Statutes and codes are amended; the linked sources are authoritative, this page is not. Last reviewed 2026-10-27.
Straight answers to the questions Minnesota homeowners ask before they call anyone.
Where the building code identifies a moderate hail area, asphalt shingles may not be applied over an existing roof covering — so a re-roof is a full…
Read the guide →The Minnesota State Building Code requires shingles designed for a 90 MPH wind speed. West St. Paul publishes a notice that shingles not meeting that…
Read the guide →Your contractor pulls the permit, not you, and it should already be priced into the quote. The city then inspects the work, which is the only…
Read the guide →Look for granule loss, cupped or cracked shingles, bare spots on south and west slopes, and anything in the attic — daylight, staining, damp…
Read the guide →Costs, materials, timelines, financing, and how we work — across roofing, siding, windows, and gutters.
Read the FAQ →We’ll walk it, photograph it, and give you a written scope that says exactly what is required and why. Retail or insurance.
We’ll walk the roof, photograph what we find, and hand you a written scope that names the code requirement behind every line. Yours to keep, whoever does the work.
We measure the work by how it holds up — and by what clients say once we're gone.