Roof Repair in Ann Arbor, Michigan

Fifteen historic districts — and the shortcut most contractors do not know about

Ann Arbor has fifteen locally designated historic districts under Michigan's Public Act 169 of 1970, with a Historic District Commission appointed by the Mayor and Council. They range from a single property to some of the largest districts in the state. The full list: Ann Street, Broadway, Cobblestone Farm, Division Street, East Liberty, East William, Fourth/Ann, Liberty Street, Main Street, Northern Brewery, Old Fourth Ward, Old West Side, the Robert and Erma Hayden House, State Street and Washtenaw/Hill.

The Old West Side alone covers 958 parcels across roughly 33 blocks, with only 78 buildings determined non-contributing. It was listed on the National Register in 1972 and locally designated in 1978, with a period of significance running 1840 to 1941. The Old Fourth Ward covers 372 properties and was resurveyed in 2023 and 2024 under a Certified Local Government grant.

Yes, a Certificate of Appropriateness is required to replace a roof in any of them. The city says so in plain language on its own FAQ page. But the part that saves Ann Arbor homeowners weeks is the Commission's Staff Approval List, which delegates 44 categories of minor work to staff without a hearing. Item 8 covers roofs, and it reads: replacement of roofs with a material exactly matching the existing top roofing layer or with the original roofing material or a replica of the missing or covered original roofing material.

So an asphalt-over-asphalt re-roof that matches what is up there now, or a restoration back to the documented original material, is a $35 staff approval. A material change is not on the list and goes to the full Commission at $100. The numbers show how the split works in practice: of 178 Certificate of Appropriateness applications decided in 2024, 138 — 78% — were approved by staff. The other 40 went to hearings, and all 40 were approved, some with conditions.

The oldest and steepest housing we work on

The median Ann Arbor home dates to 1971, but the median hides the two things that actually shape the work here.

First, the pre-war layer. 8,026 units — 14.8% of all housing in the city, about one in seven — was built in 1939 or earlier. Nearly 20% predates 1950, and 48.2% was built in 1969 or earlier. The largest single decade is the 1960s at 18.5%, which means an enormous middle layer is now 55 to 65 years old.

Those old houses are not simple. The Old West Side survey describes the district's housing as predominantly vernacular — one-and-a-half or two-story gable-front houses plus front- and side-gable bungalows, with roof forms including gable-front, side-gable, hip, cross-gable-and-hip, jerkinhead clipped gables, and shed dormers. Jerkinhead roofs alone will tell you what you are dealing with: more planes, more intersections, more flashing per square, and a lot of it hand-detailed rather than off a truck.

Second, tenure. Ann Arbor is a majority-renter city — 27,544 of 50,499 occupied units, 54.5%, are renter-occupied. Single-family detached is 41.6% of the stock; add attached and it is 53.9%. Practically, that means a very large share of the roofs in this town belong to a landlord rather than the person living under them, and quite often to an absentee one. We work with owners, property managers and associations, and we are used to the fact that the person who notices the leak is not always the person who signs.

What we get called out for most in Ann Arbor:

A city named for trees, with an ordinance that mostly leaves your yard alone

Ann Arbor's published urban tree canopy assessment puts existing canopy at 32.9% — about 6,015 acres across the roughly 29 square miles inside the city limits — with canopy in the public right-of-way at 23.7%. Residential and recreation land makes up 58% of the city but carries 67% of its canopy. The city's forest management plan sets a 30-year residential canopy goal of 60%, up from 37%. The city manages 51,806 inventoried trees with an estimated replacement value of $92 million, and an iTree analysis puts the community-wide total at over 1.45 million trees.

Worth noting for accuracy: that canopy assessment dates to 2010 and is still the one the city links from its forestry pages, so treat it as the published figure rather than a current-year measurement.

The tree rules are more homeowner-friendly than people expect, and the exceptions are the interesting part. The city's development code regulates landmark trees and woodlands on private property by requiring a site plan — but those regulations apply to all private property except single-family and two-family parcels zoned solely for residential purposes. A landmark tree is any tree 24 inches in diameter at breast height or greater, or one on the city's landmark tree list, excluding invasive species.

So on a normal single-family lot outside a historic district, the landmark tree requirement does not apply to you. Inside a historic district it does: the Historic District Commission regulates removal of landmark trees on all private property in a district, including residential parcels — and the staff approval list requires a written statement from a professional service or arborist confirming that historic trees or plantings are dead, diseased or damaged.

And any tree in the public right-of-way is a city tree. Removal, planting, trimming, fertilisation, disease treatment and even stump grinding all require a permit. The permit itself is free, but a canopy loss fee or a tree appraisal may be charged for removing a city street or park tree. City Forestry is at 734.794.6320.

The practical version for a roof: if the limb over your shingles is on your own single-family lot outside a district, it is your call. If it is in the tree lawn between the sidewalk and the street, it is the city's, and that call goes to Forestry first.