Pest Control in Detroit, Michigan

Detroit’s Housing Is Far Older Than the Michigan Average

The single fact that shapes pest work in Detroit more than any other is the age of its buildings. The U.S. Census Bureau’s 2024 American Community Survey counts 343,649 housing units in the city, and 127,024 of them — about 37 percent — were built in 1939 or earlier. Another 73,480 went up during the 1940s, which means close to six in ten Detroit homes predate 1950. Statewide, only about 14.5 percent of Michigan’s housing stock dates to 1939 or earlier, so Detroit’s share of pre-war homes is roughly two and a half times the state rate.

Age matters because old houses give pests more ways in. Brick and block foundations lose mortar, wood sills settle, basement windows loosen and decades of plumbing, gas and cable work leave holes through the walls. Michigan State University Extension advises that any gap leading outdoors that is larger than a quarter inch be sealed, and it recommends durable materials such as concrete mortar, sheet metal or heavy hardware cloth over spray foam, which mice can chew through. In a pre-war Detroit two-flat, an inspection can turn up openings that size anywhere from the foundation to the roofline.

The city’s population also shapes the picture. The 2020 Census counted 639,111 residents in Detroit, and the ACS estimates that about one in five housing units in the city is not occupied. Occupied homes sit beside vacant structures and open lots on many blocks, which is one reason Detroit’s Property Maintenance Code specifically extends its rat-proofing requirement to vacant and unimproved property.

What the City Handles, and What It Leaves to Owners

Detroit callers are often surprised to learn how narrow the city’s pest role is. Rodent issues fall under the Buildings, Safety Engineering and Environmental Department (BSEED). Its Environmental Enforcement section describes its work as investigating and educating the public about rodent infestations through exterior residential rodent baiting. The same section enforces portions of Chapter 8 (Property Maintenance) and all of Chapter 42 (Solid Waste) of the City Code, and it issues violations for rat harborage, illegal dumping and solid waste left on a property.

What BSEED does not do is come inside. The department’s own FAQ states that the City of Detroit does not provide interior rodent extermination services and that residents need to contact a private company. Outdoor rodent complaints go through the city’s Improve Detroit reporting system. In practice that means a household with mice in the kitchen, or rats nesting under a back porch, is dealing with the city for the alley and the vacant lot next door and with a private licensed company for everything on and inside the house.

Detroit’s Rules on Infestations in Rental Housing

Because roughly half of Detroit’s occupied homes are rented — the ACS counts 131,427 renter-occupied units out of 268,048 occupied units — the question of who pays for extermination comes up constantly. Detroit’s Property Maintenance Code answers it in several parts:

• All buildings must be kept free of infestation. Where an infestation occurs, it must be promptly exterminated by an approved process that is not injurious to human health, and precautions must follow to prevent reinfestation.
• Before renting or leasing, the owner is responsible for extermination within the building and for giving a prospective tenant copies of any extermination records by a licensed exterminator from the past year.
• In a one-family dwelling, the occupant is responsible for extermination — unless the infestation is caused by defects in the building, in which case the owner is responsible.
• In buildings with two or more dwelling units, the owner must post or distribute BSEED’s infestation and extermination information, is responsible for extermination in all areas of the building and the exterior property, and must provide BSEED with documentation showing that a tenant’s vermin complaint has been resolved.

Those rules make paperwork part of the job. A landlord in a Detroit fourplex usually needs a licensed company that leaves written service records, and a tenant in a single-family rental has reason to document whether the entry points were structural defects. Exterminator Dispatch does not interpret the code for any specific situation; the text is published by the city, and questions about a particular property belong with BSEED.

The Pests Behind Most Detroit Calls

House mice and Norway rats

Rodents are a standing concern in older Detroit housing. The National Weather Service office for Detroit/Pontiac notes that October is the month the growing season ends across Southeast Michigan, and MSU Extension points out that falling temperatures send mice looking for warm shelter. Rat work in Detroit usually has two halves: exterior baiting and harborage cleanup, some of which BSEED addresses on the public side, and exclusion work on the house itself. In Michigan, rodent work using pesticides falls under MDARD’s Category 7D, Vertebrate Pest Management.

German cockroaches

MSU’s Plant and Pest Diagnostics lab identifies the German cockroach as the most common cockroach found inside houses. It favors warm, humid spots around 70 degrees Fahrenheit, which puts it in kitchens and bathrooms first, and it can produce three to four generations a year. In Detroit’s shared-wall walk-ups and older apartment blocks, a German roach problem in one unit can spread beyond it, and the city code assigns multi-unit extermination to the owner.

Bed bugs

Michigan’s state bed bug manual, produced by the former Michigan Department of Community Health, warns that bed bugs in one unit may spread to the units beside, above and below it, and advises inspecting adjacent units and treating them as infested if bed bugs are found. For a Detroit apartment building, that turns a single-unit call into a building-level plan.

Eastern subterranean termites

MSU describes subterranean termites as the most serious wood-destroying pest in Michigan and more common than most people realize. The eastern subterranean termite nests in moist soil and can reach wood that does not touch the ground by building mud shelter tubes over or through concrete foundations. Winged termites inside a home strongly indicate an active infestation. Termite work in Michigan falls under MDARD Category 7B, Wood Destroying Pest Management.

Mosquitoes

West Nile virus is a recurring summer concern across the metro. The Macomb County Health Department describes West Nile virus as endemic in Macomb County and tests mosquito pools through the spring and summer to track infected mosquitoes. Its prevention guidance centers on emptying standing water from gutters, buckets, flowerpots, pool covers, discarded tires and birdbaths. Commercial outdoor mosquito treatment in Michigan is its own MDARD certification category, 7F.

ZIP codes served

Requests are accepted from every Detroit ZIP code, including:

Verifying that a Detroit exterminator is actually licensed

Michigan regulates pest control through the Michigan Department of Agriculture and Rural Development. Two credentials matter. First, the individual applicator: MDARD certifies commercial applicators by category, and a certification credential is valid for three years, expiring on December 31 of the third year. Registered applicators may apply general-use pesticides only under the supervision of a certified applicator. Second, the company: MDARD requires a pesticide application business license to apply pesticides for hire, and certification alone does not allow someone to run a pest control business. To hold that license, the business must be a certified applicator or employ one whose credentials cover each category it is licensed in, and it must file proof of general liability insurance with MDARD. Business licenses expire every year on December 31.

For a Detroit job, ask which categories the company is licensed in — 7A for general indoor pests, 7B for termites and carpenter ants, 7D for rats and mice, 7F for outdoor mosquito work — and confirm them. MDARD publishes a public lookup for applicator certification credentials on its pesticide licensing pages, and the department can be reached at 800-292-3939. Every company in the Exterminator Dispatch network is an independently owned, Michigan-licensed business; it is still reasonable for a caller to check.