Roofing Laws in Minnesota (2026): Winter Weather Rules Inside

Most people think roofing is just about nails and shingles. Not even close. In Minnesota, strict laws govern every single roofing project. Breaking these rules can hit you with fines, stop your project cold, and create serious headaches when you try to sell your house. Let’s break down what you actually need to know.

Minnesota winters are brutal. The state’s roofing laws reflect that reality. These regulations exist to protect homeowners from shoddy work that can’t handle heavy snow, ice dams, and subzero temperatures.

What Are Minnesota Roofing Laws?

Minnesota roofing laws are part of the bigger Minnesota State Building Code. The current version follows the 2020 Minnesota Residential Code. This code is based on the 2018 International Residential Code.

Think of these laws as your safety net. They set minimum standards for how roofs must be built. The rules cover everything from the slope of your roof to the type of underlayment used.

These laws apply statewide. Every city and county must follow them. Some areas have additional local requirements on top of the state rules.

The code gets updated every six years. The last update happened in March 2020. The next one is expected around 2026.

Who Needs a License to Do Roofing Work?

Here’s where it gets serious.

Anyone doing roofing work on homes in Minnesota must have a license. There are three types of licenses that allow roofing work. Each one comes with different permissions.

Residential Roofer License

This license only covers roofing work. Nothing else. If you want to install gutters or fascia, you need a different license. Most dedicated roofing companies have this one.

Residential Building Contractor License

This is the most flexible option. Contractors with this license can do roofing plus other construction work. They can work on existing homes and build new ones.

Residential Remodeler License

Similar to the building contractor license but limited. Remodelers can do roofing and other work, but only on existing structures. No new construction allowed.

Wondering if your contractor needs a license? Yep, they definitely do.

The only exception is small operations. Contractors making less than $15,000 per year in gross receipts are exempt. They still need to get a Certificate of Exemption though.

Roofing subcontractors don’t need a license. But they must register through the Construction Contractor Registration Program.

Working without a license is a misdemeanor in Minnesota. That’s a criminal charge. Don’t mess around with this.

Getting a Roofing License in Minnesota

The licensing process involves several steps. It’s not complicated, but you need to do everything right.

Step 1: Register Your Business

Register with the Minnesota Secretary of State first. This creates your legal business entity. You’ll need this paperwork before you can apply for a license.

Step 2: Pass the Exam

Every company needs a “qualifying person.” This person takes the licensing exam on behalf of the company. No experience or education requirements exist to take the test. Anyone can try.

The exam has 110 multiple choice questions. You get five and a half hours to finish. A score of 70% or higher is required to pass.

About 60% of the questions cover the Minnesota Residential Building Code. The rest deal with statutes and rules governing construction.

Don’t pass on your first try? You must wait 30 days before retaking the exam. You’ll need to submit a new application and pay another fee.

Step 3: Submit Your Application

After passing the exam, you get instructions on how to apply for the license. The application requires several documents.

You’ll need a $15,000 surety bond. This protects homeowners if you violate licensing laws. No credit check is required for this bond.

Liability insurance is mandatory. Minimum coverage is $300,000 per occurrence with at least $10,000 in property damage coverage.

Workers’ compensation insurance is required if you have employees. If you don’t have employees, you need a written explanation of why you’re exempt.

Unemployment insurance documentation is also necessary. Same deal as workers’ comp.

The license fee is $180. This fee is the same regardless of when you apply during the license period.

Step 4: Maintain Your License

Licenses expire on March 31 each year. You must renew before this date.

The qualifying person must complete 14 hours of continuing education every two years. No exceptions. This keeps your knowledge current as codes change.

Building Permits for Roofing Projects

Every roofing project in Minnesota requires a building permit. Seriously, every single one.

This applies to both new roofs and re-roofing jobs. Even repairs larger than 10 feet by 10 feet need a permit in some cities.

You get permits from your local building department. In Minneapolis, that’s at the Public Service Building. Other cities have their own offices.

Permit fees vary by location. Your city or county sets the amount. Expect to submit plans and pay a fee.

Hold on, this part is important. Inspections happen at various stages during your roofing project.

Most projects require at least two inspections. The first checks your roof deck and ice barrier installation. The second is a final inspection when everything is complete.

Some cities now accept digital photos instead of in-person inspections for certain stages. Check with your local building department.

Starting work without a permit is illegal. You could face stop-work orders and fines. Insurance companies may also refuse claims on unpermitted work.

Minnesota Roofing Code Requirements

Okay, let’s talk about the actual building requirements. These rules determine how your roof must be constructed.

Minimum Roof Slope

Asphalt shingles must be installed on roofs with at least a 4:12 slope. That means 4 inches of rise for every 12 inches of horizontal distance.

For slopes between 2:12 and 4:12, special double underlayment is required. Honestly, most contractors just avoid these low slopes.

Ice and Water Barrier

This is huge in Minnesota. Ice dams are a massive problem here.

Every roof needs an ice barrier at the eaves. This barrier must extend at least 24 inches past the interior wall line. Not 20 inches. Not 22 inches. At least 24 inches.

The barrier can be two layers of underlayment cemented together. Or you can use a self-adhering polymer modified bitumen sheet. Most contractors prefer the self-adhering type.

Valleys need ice barriers too. They must run the full length of the valley.

Detached garages don’t require ice barriers. That’s the only exception.

Underlayment Requirements

All roofs need underlayment beneath the shingles. This is that black, paper-like material you might have seen.

The minimum is 15-pound roofing felt. It must be installed shingle fashion. That means overlapping correctly as you go up the roof.

Horizontal laps must be at least 2 inches. Vertical end joints need a 6-inch overlap minimum.

For low-slope roofs between 2:12 and 4:12, double underlayment is mandatory. The installation pattern gets more complex for these roofs.

Roof Deck Sheathing

Asphalt shingles require solid roof decking. Spaced boards won’t work.

Acceptable materials include plywood, OSB, or 1-inch nominal boards. The sheathing must be in good condition. Rotted or damaged decking must be replaced before roofing.

If you’re re-roofing and find gaps bigger than half an inch between boards, you must fix this. You can install strips of 1×4 boards in the spaces.

Ventilation

Proper attic ventilation is required by code. This prevents moisture buildup and ice dams.

The minimum ventilation is 1 square foot for every 150 square feet of attic space. You can reduce this to 1:300 if you meet specific conditions.

At least 50% of vents must be in the upper portion of the roof. The rest should be at eaves or cornices. All vents must be at least 3 feet apart vertically.

Flashing Requirements

All roof penetrations and intersections need proper flashing. This includes chimneys, walls, valleys, and vent pipes.

Metal flashing is required at most locations. The code specifies installation methods for different situations.

Kick-out flashing is mandatory when re-roofing and re-siding at the same time. This prevents water from running down walls.

Manufacturer’s Instructions

Here’s something most people miss. You must follow the manufacturer’s installation instructions.

If the code and manufacturer’s instructions conflict, you follow whichever is stricter. This ensures your roof performs correctly.

Not following manufacturer’s instructions can void your warranty. Insurance companies hate this too.

Roof Overlay Rules

You might be wondering if you can just put new shingles over old ones. The answer is maybe.

Minnesota allows one roof overlay. You can install new shingles over one existing layer. That’s it. Two layers total maximum.

If you already have two layers, you must tear everything off before re-roofing. No exceptions.

Overlays can save money upfront. But they have downsides. Extra weight can stress your roof structure. Ventilation can become problematic.

Most roofing experts recommend tear-offs instead of overlays. You get to inspect and repair the deck. The new roof lasts longer.

If you do an overlay, the existing shingles must be in decent shape. They need to provide a flat, stable base.

Penalties for Breaking Roofing Laws

Breaking these laws has real consequences. Let’s be clear about what can happen.

Working Without a License

Operating without a required license is a misdemeanor in Minnesota. That’s a criminal charge that goes on your record.

Contractors face administrative penalties too. The Department of Labor and Industry can issue fines and enforcement actions.

Permit Violations

Starting work without a permit can result in stop-work orders. Your project gets shut down until you fix the problem.

Cities and counties can issue fines for permit violations. The amounts vary by location.

Code Violations

Building inspectors can fail your inspection if work doesn’t meet code. You’ll need to fix the problems and get re-inspected.

Homeowners who sell a house with code violations can face liability issues. Buyers can sue for undisclosed problems.

Insurance companies may deny claims on roofs that don’t meet code. This is a big deal if you have storm damage.

OSHA Violations

Safety violations during roofing work carry serious penalties. These come from Minnesota OSHA (MNOSHA).

Serious violations can result in fines from $1,500 to $16,550 per violation. Willful violations can hit $165,514 per violation.

If a safety violation contributes to an employee death, minimum fines start at $25,000 to $50,000.

How to Verify a Roofing Contractor

You’re not alone if you’re not sure how to check if a contractor is legit. Most people don’t know how to verify this stuff.

Check Their License

Ask to see the contractor’s license before signing anything. Licensed contractors should have no problem showing you their credentials.

You can verify licenses online through the Minnesota Department of Labor and Industry website. Just search for the company name or license number.

Make sure the license type matches the work being done. A residential roofer license only covers roofing. If they’re also doing siding, they need a different license.

Verify Insurance

Request certificates of insurance. The contractor should carry liability insurance and workers’ compensation.

The liability insurance must be at least $300,000 per occurrence with $10,000 property damage coverage.

Workers’ comp is required if the contractor has employees. Don’t skip this step. You could be liable if an uninsured worker gets hurt on your property.

Check References and Complaints

Ask for recent references. Call them. Ask about the quality of work and whether the contractor followed through.

Check the Better Business Bureau for complaints. The Minnesota Attorney General’s Office also tracks complaints against contractors.

The Department of Labor and Industry maintains enforcement action records. You can see if a contractor has been disciplined.

When to Get Professional Help

Some roofing work you can maybe do yourself. Most of it you can’t.

DIY roofing is legal if you own the property and live there. You still need permits and inspections. Your work still must meet code.

Most homeowners should hire licensed professionals. Here’s why.

Roofing is dangerous. Falls from roofs cause serious injuries and deaths every year. Professional roofers have safety equipment and training.

Code compliance is complex. One mistake can cause expensive problems later. Licensed contractors know the requirements.

Warranty protection matters. Manufacturer warranties often require professional installation. DIY work might void coverage.

Insurance claims can get denied if work isn’t done by licensed professionals. This is especially true for storm damage repairs.

Common Roofing Mistakes to Avoid

These are the problems that trip people up most often.

Skipping the Permit

Never start work without a permit. The fines and hassles aren’t worth the money you might save.

Hiring Unlicensed Contractors

Storm chasers often show up after hail damage. Many aren’t licensed. Don’t hire them. You’ll have no recourse if they do bad work.

Ignoring Ice Barrier Requirements

The 24-inch ice barrier isn’t optional in Minnesota. Ice dams will destroy your roof without proper protection.

Using Wrong Materials

Not all roofing materials work in Minnesota’s climate. Make sure your contractor uses products rated for severe weather.

Poor Ventilation

Skimping on attic ventilation causes moisture problems and ice dams. Follow the code requirements exactly.

Not Following Manufacturer Instructions

This voids warranties and can cause premature failure. Always install materials according to specifications.

Frequently Asked Questions

Do I need a permit to replace my roof in Minnesota?

Yes, you need a building permit for all roofing projects in Minnesota. This includes new roofs, re-roofing, and major repairs over 100 square feet in most cities.

Can I install a new roof over existing shingles?

Yes, but only if you currently have just one layer of shingles. Minnesota code allows a maximum of two total layers. If you already have two layers, you must tear everything off first.

How much does a roofing license cost in Minnesota?

The license fee is $180. But you’ll also need a $15,000 surety bond, liability insurance, and workers’ comp insurance. The total cost to get licensed is several thousand dollars.

What happens if I hire an unlicensed roofer?

You have no protection through the Contractor Recovery Fund. If the work is bad or the contractor disappears, you’re out of luck. Insurance claims may also be denied for work done by unlicensed contractors.

How long does a roofing permit take in Minnesota?

Most cities issue roofing permits the same day you apply. The application process is usually quick as long as you have all required documents.

What is the minimum slope for a roof in Minnesota?

For standard asphalt shingles, the minimum slope is 4:12. That means 4 inches of vertical rise for every 12 inches of horizontal run. Slopes between 2:12 and 4:12 require special double underlayment.

Do I need ice barrier on my garage roof?

Detached garages don’t require ice barriers under Minnesota code. However, ice barriers are mandatory on all attached structures and houses.

Can homeowners do their own roofing work?

Yes, homeowners can work on their own primary residence. You still need permits and inspections. Your work must meet all code requirements just like a professional installation.

What insurance do roofing contractors need in Minnesota?

Contractors must carry liability insurance of at least $300,000 per occurrence with minimum $10,000 property damage coverage. Workers’ compensation insurance is required if they have employees.

How do I file a complaint against a roofing contractor?

File complaints online through the Minnesota Department of Labor and Industry website. You can also contact the Minnesota Attorney General’s Office for consumer protection issues.

Final Thoughts

Minnesota roofing laws are strict for good reason. Harsh winters demand quality work. The rules protect homeowners from shoddy construction that fails when you need it most.

Always use licensed contractors. Get permits before starting work. Follow code requirements exactly.

These steps ensure your roof will handle Minnesota’s brutal weather. They also protect your investment and keep insurance valid.

When in doubt, contact your local building department. They can answer specific questions about your project. Stay informed, follow the rules, and your roof will last for decades.

References

1. Minnesota Department of Labor and Industry – Residential Contractors: https://www.dli.mn.gov/business/residential-contractors-remodelers-roofers
2. Minnesota Department of Labor and Industry – Roofer License Requirements: https://dli.mn.gov/business/residential-contractors/who-needs-roofer-license
3. 2020 Minnesota Residential Code: https://www.dli.mn.gov/sites/default/files/pdf/edu_roofing.pdf
4. Minnesota Statutes Chapter 326B – Building Codes and Standards: https://www.revisor.mn.gov/statutes/cite/326B
5. Minnesota Attorney General’s Office – Home Building and Remodeling: https://www.ag.state.mn.us/consumer/handbooks/HmBuilding/