Ann Arbor Requirements Explained

You’re planning a deck or looking at your existing one and wondering about railings. Do you legally need them? Can you skip them to save money or preserve the view?

The answer comes down to one measurement: how high your deck sits above the ground. In Ann Arbor, the rules are clear but there are local twists that catch homeowners off guard.

Let’s break down exactly when you need railings, what specifications they must meet, and how Ann Arbor’s requirements differ from basic state code.

The 30-Inch Rule

If your deck surface sits more than 30 inches above the ground at any point, you need a railing. This isn’t a suggestion. It’s Michigan law.

Ann Arbor follows the 2015 Michigan Residential Code. Section R312.1 covers this requirement. The measurement is taken vertically from your deck surface down to the grade below, measured at any point within 36 inches of the deck edge.

Under 30 inches: No railing required by code. You can add one for safety, but it’s optional.

Over 30 inches: Railing is mandatory everywhere the deck exceeds this height.

The cutoff is strict. A deck that measures 29 inches above grade doesn’t need a railing. One that measures 31 inches does.

Why Railings Matter

Safety comes first. Falls from elevated decks cause serious injuries. Railings prevent accidental falls, especially for children, elderly guests, or anyone who loses their balance.

Accessibility helps everyone. Railings give people something to grab when moving around the deck or using stairs. This matters for seniors, anyone with mobility issues, and kids learning to navigate spaces safely.

Property value and curb appeal. Well-designed railings enhance your home’s appearance. During resale, buyers and inspectors will check for code compliance. Missing required railings create problems at sale time.

Required Railing Specifications

When railings are required, they must meet specific safety standards. You can’t just nail up some boards and call it done.

Height: Minimum 36 inches tall, measured from the deck floor to the top of the rail. Some homeowners go higher for extra safety or better views over the railing.

Baluster spacing: Vertical spindles must be close enough that a 4-inch sphere cannot pass through. This is called the 4-inch sphere rule. It prevents small children from slipping through or getting their heads stuck between balusters.

Strength: Your railing must withstand a 200-pound concentrated load pushed against it from any direction. This ensures it won’t collapse if someone falls against it or children push on it.

Stair Requirements

Stairs have their own rules beyond the deck surface requirements.

Stairs need guardrails on at least one side regardless of deck height. Long stair runs or stairs with multiple level changes may require railings on both sides.

Handrails must be continuous along the stair run. They should be graspable and positioned at a height that’s comfortable for most people to use while climbing or descending.

The same 4-inch sphere rule applies to stair balusters. No gaps large enough for a child to squeeze through.

Ann Arbor’s Local Twists

Ann Arbor follows state code for safety requirements but adds local zoning rules that trip up many homeowners.

The Permit Exemption Trap

Michigan code says small, low decks under 200 square feet, under 30 inches high, and not attached to the house are exempt from building permits.

Ann Arbor still requires a Zoning Compliance Permit even for these small decks. Why? The city needs to verify your deck isn’t too close to property lines or covering too much of your lot. Setback rules and lot coverage limits apply regardless of whether you need a railing.

Don’t assume “no building permit needed” means “no permits at all.” Check with Ann Arbor’s building services before starting any deck project.

Historic District Complications

Living in Old West Side, Kerrytown, Germantown, or another historic district creates additional challenges.

Modern safety code requires 36-inch railings. Historic homes often had lower railings, sometimes 28-32 inches. This creates a conflict between safety requirements and historic preservation.

Safety code wins. You must meet the 36-inch minimum. But the Historic District Commission will scrutinize your railing style and materials. Standard vinyl kits from big box stores won’t pass review. You’ll likely need wood railings with specific profiles that match your home’s era.

Get a Certificate of Appropriateness from the Historic District Commission before applying for your building permit. Skipping this step causes delays and potential rejection of your plans.

Checking Your Local Requirements

Contact Ann Arbor Building Services directly. Ask about current amendments to Michigan code and confirm the exact requirements for your property.

Check the city’s code portal. Ann Arbor maintains online resources showing current building requirements and any recent changes.

Verify specifics for your situation. Minimum railing height, maximum opening spacing, stair requirements, and permit needs. Don’t rely on what worked for your neighbor’s deck three years ago.

Consult a licensed contractor familiar with Ann Arbor codes. Experienced local builders know the requirements and common inspection issues. They can spot problems before you start building.

Choosing Railing Materials

Your railing needs to meet code, but you still have choices in materials and style.

Wood: Traditional look that fits most Ann Arbor homes. Requires regular maintenance with Michigan’s freeze-thaw cycles. Plan to repaint or restain every few years.

Aluminum: Durable and lightweight. Won’t rust. Good for modern designs. Handles snow and ice without problems.

Glass panels: Unobstructed views. Modern look. Higher cost. Requires regular cleaning to look good. Check code requirements carefully as glass railings have specific strength and mounting requirements.

Consider Michigan winters when choosing materials. Snow load on horizontal rails, ice buildup, and repeated freeze-thaw cycles affect different materials differently.

Measuring Your Deck

Before calling building services or a contractor, measure your deck height yourself.

Go outside with a tape measure. Measure from where your deck floor sits down to the ground below. Take measurements at several points because ground level changes.

If your measurements are close to 30 inches, grading the dirt up slightly can sometimes bring you under the requirement. Adding a few inches of soil near the deck might save you the cost of installing railings.

Be honest with your measurements. A deck that’s 31 inches high needs railings whether you report it accurately or not. Inspectors will check during the permit process.

The Permit Process

Check out this article: Do I Need a Permit for My Deck?

All Ann Arbor permits go through the STREAM online system. You’ll submit your plans, pay fees, and track your application status through this portal.

Building permits typically require:

• Site plan showing deck location and setbacks from property lines
• Deck design with dimensions and materials
• Railing details if required
• Structural calculations for elevated decks

Zoning compliance permits need:

• Property survey or accurate site plan
• Deck dimensions and location
• Setback measurements

Allow time for plan review. Ann Arbor building department reviews can take several weeks depending on workload and complexity of your project.

Common Questions From Ann Arbor Homeowners

Do I need a railing if my deck is low?

Check the exact height. If you’re under 30 inches at all points, no railing is required by safety code. But stairs may still need railings even on low decks.

Can I install railings myself?

Yes, if you’re comfortable with the work and willing to meet code requirements for post anchoring, baluster spacing, and strength. Many DIY railing projects still require permits and inspections.

What if I remove existing railings?

Don’t remove railings on elevated decks. If your deck is over 30 inches high, removing railings puts you out of code compliance. This creates liability issues and problems when selling your home.

Are there grants or rebates for deck safety upgrades?

Check with Ann Arbor’s building services or Washtenaw County for any current safety improvement programs. These programs change, so verify what’s available now.

What happens if I build without required railings?

Code violations create problems. You might face fines. Your homeowner’s insurance could deny claims if someone is injured. Future home sales will require bringing the deck up to code before closing.

Quick Checklist for Ann Arbor Deck Owners

• Measure your deck height from surface to grade at multiple points.
• Check if you’re in a historic district using Ann Arbor’s historic district map.
• Contact building services to confirm current railing requirements for your specific situation.
• Decide on railing material that handles Michigan weather and fits your home’s style.
• Verify whether you need a building permit, zoning permit, or both.
• If in a historic district, apply for Certificate of Appropriateness before other permits.
• Hire a qualified installer or ensure your DIY work meets all code requirements.
• Schedule required inspections before considering the project complete.

Getting It Right

Deck railings aren’t optional on elevated decks. The 30-inch rule is straightforward, but Ann Arbor’s local requirements add complexity.

Measure carefully. Check with building services. Get the right permits. Use appropriate materials for your situation. Install railings that meet code requirements.

Done correctly, your railings keep everyone safe, satisfy inspectors, and avoid problems when you eventually sell your home.