Farmington Hills particulars
Roughly half of Farmington Hills housing is older than 1980: 53.7 percent of homes were built before then, and older houses tend to carry older furnaces and ductwork. The median home value is $333,200. Homeowners pulling their own mechanical permit face an extra step. Instructions on the Building Division's page, effective August 2026, require a signed, notarized Homeowner Affidavit attached to each BS&A Online permit application, followed by online payment.
Contractors register with the city instead. The page does not name mechanical permit types, so confirm the right category with the division at 248-871-2450, 31555 W. Eleven Mile Road. The city also runs a mandatory Single-Family Rental Dwelling Registration, Safety and Maintenance Inspection Program for rentals. For heat, we use the Detroit Metro airport normals as our nearest station, about 6,067 heating degree days a year (base 65 F). Only DTE Electric reaches Farmington Hills, and the gas is mostly Consumers Energy; confirm by address if you live near a boundary.
A gas furnace replacement points to Consumers Energy's 2026 chart (installs January 1 to December 31, 2026; amounts can change without notice). Farmington, Novi and Southfield have their own offices; for a new thermostat, see thermostat.
Furnace repair in Farmington Hills: what to know
We take Farmington Hills' heating load from the Detroit Metro airport normals as the nearest station we read: about 6,067 heating degree days a year at base 65 F. Gas is mostly Consumers Energy, since all 182 sample points fell in its territory, with a sliver of DTE Gas, so border streets need an address check. At 53.7 percent built before 1980, the housing is among the newest of the large cities.
If the repair becomes a replacement, the Building Division at 31555 W. Eleven Mile Road (248-871-2450) takes permits in BS&A Online. Contractors register with the city. A homeowner must attach a signed, notarized Homeowner Affidavit to each application under instructions effective August 2026, then pay online. The page does not name mechanical permits, so ask which category to choose.
Permits for furnace repair in Farmington Hills
LARA's rule says mechanical work needs a permit except for replacement of minor parts, so a repair that swaps a part generally does not, while replacing the furnace does (our reading of LARA's exemption list).
Furnace problems that cannot wait
- You smell gas: leave, then call 911 and your gas utility from outside.
- A carbon monoxide alarm is sounding: get into fresh air, call 911 and stay out until told it is safe (see the carbon monoxide guide).
- Several people have flu-like symptoms without a fever; SEMCO lists headache, fatigue, nausea and dizziness as carbon monoxide symptoms.
- No heat in freezing weather: see emergency HVAC repair.
- A furnace that heats but runs louder than it used to, with no gas smell and no alarm.
Three checks before you call
Try this first: if you plan to pull your own permit, get the affidavit notarized before the day the equipment arrives.
- Set the thermostat to heat, above the room temperature, with fresh batteries if it takes them.
- Check the filter and change or clean it; ENERGY STAR says to do this monthly.
- If it still will not start, note any light pattern or code and stop. Do not remove panels or relight anything after a gas smell.
What furnace repair costs
The estimate below is the Michigan-wide one, adjusted for Michigan wages and not for Farmington Hills in particular. The same table is on the furnace repair page. How we estimate costs. Prices as of Oct 19, 2026.
| Item | Figure | What it is |
|---|---|---|
| Estimated range, not a quote | $105 to $550 per repair | Built from one national published range, adjusted by the Michigan HVAC technician wage ratio (1.00). |
| Technician wage, Michigan mean | $31.01 an hour | Technician pay (BLS, May 2025), not a price. |
| Furnace replacement permit, Grand Rapids | $21 plus a $52 application | Effective July 1, 2026; $73 by our addition. |
| Gas or oil furnace permit, Sterling Heights | $57 up to 75,000 BTU, plus $55 application | 2026-2027 form. |
| Heating system permit, Dearborn | $50 up to 75,000 BTU | Plus $100 administrative fee. |
| Residential furnace permit, Westland | $83 up to 75,000 BTU | Plus $100 administration fee. |
| Residential furnace permit, Warren | $80 | Form dated 4/25/2023; confirm with the city. |
| Residential heating system permit, LARA state | $50 plus a $75 application | Only where the state enforces the code. |
How we estimate costs: the figures here are estimates, not quotes, built from BLS wages, published city permit fees and federal energy-cost evidence. We are collecting the prices Michigan heating and cooling companies publish; we have not yet collected quotes from them, and we will say how many and from when once we do. Estimated range. Built from national published ranges (1 source), adjusted by Michigan's HVAC technician wage ratio to the US (1.00, BLS May 2025), plus the local permit fee where the city publishes one. Not a quote. We have too few Michigan company prices yet to show a range. Full method.
Questions about furnace repair
What is the average lifespan of a furnace?
The federal and ENERGY STAR pages we could read give none. ENERGY STAR does say equipment more than 10 years old should be evaluated by a professional HVAC contractor, which is a reason to ask for an inspection and gives no expiry date.
How much does furnace repair or a service call cost in Michigan?
The first row of the cost table is a statewide estimate, a model and not a quote. The rows below show technician wages, a Michigan mean of $31.01 an hour (BLS, May 2025), which is pay, not a charge. Ask what the visit fee covers and get the repair price in writing before work starts.
What is the $5,000 rule for furnaces?
Contractors and homeowners pass it around, but no federal or state page we read states it. The repair-or-replace tool shows it only as a labeled rule of thumb; ENERGY STAR's 10-year evaluation advice is the sourced alternative.