Many comfort problems in Detroit homes start in the ducts, not the furnace. Old ducts from gravity or coal furnaces, missing returns and leaks into cold basements and attics are common. Fix the ducts and any furnace or AC works better.
Price ranges on this page are national figures published by HomeGuide for 2026. They are not our quotes. Your house, the equipment you choose, the venting and the ductwork move the real number up or down. Last checked October 2026.
Is duct cleaning worth it, and what does it cost?
Duct cleaning is worth it after a renovation, a pest problem, water damage or many years of neglect, but it does not fix most dust or comfort problems. Whole-house duct cleaning costs $450 to $1,000, by HomeGuide's duct cleaning page, or $25 to $50 per supply vent.
That page suggests cleaning every 3 to 5 years, and other HomeGuide pages say 3 to 7. If the ducts look clean inside, you can skip it. Ask the cleaner to show you before and after photos.
Why are some rooms hotter or colder than others?
Some rooms are hotter or colder because they get too little air, have no return path, or lose heat through poor insulation and windows. Upstairs rooms in Detroit bungalows and story-and-a-half homes are the classic case: hot in summer, cold in winter.
Fixes include balancing dampers, adding a return, sealing ducts, adding attic insulation, or a ductless unit for the problem room. We measure airflow room by room to find the cause.
How much does it cost to replace or add ductwork?
Ductwork replacement costs $1,400 to $5,600 on average, with a national average of $3,500, by HomeGuide's ductwork page. That is $25 to $55 per linear foot. New ductwork in a house that has none costs $2,400 to $6,600, or $40 to $65 per linear foot.
Basement duct runs cost the least, listed at $1,800 to $3,100, and attic work $2,200 to $5,600. Adding ducts to an old Detroit house with plaster walls means planning chases and closets carefully.
How do I know if my ducts are leaking?
Signs your ducts are leaking include rooms with weak airflow, a dusty house, a very warm basement in winter, and high bills. Look for disconnected joints, gaps and crushed flex duct in the basement or attic. A duct leakage test, listed at $250 to $400 nationally, measures it.
Leaky ducts can be sealed by hand with mastic or with an aerosol sealing system. HomeGuide lists manual sealing at $400 to $1,900.
Do I need a whole-house humidifier in Michigan?
Many Michigan homes benefit from a whole-house humidifier, because cold outdoor air is very dry once it is heated. Signs include static shocks, dry skin, cracked wood floors and gaps in trim. HomeGuide lists a whole-home humidifier at $400 to $1,200 installed.
Too much humidity in winter causes window condensation and mold, so set it moderately and lower it in the coldest weather.
Can I add an air purifier to my furnace?
Yes, you can add an air purifier or air cleaner to most furnaces. Options include thicker media filters, electronic air cleaners and UV lights. HomeGuide lists whole-house air purifiers at $400 to $4,000.
The best first step is usually a good media filter, sized for your furnace so it does not choke the airflow. Some products promise more than they deliver, so ask what each one removes.
My old ducts have asbestos tape. What do I do?
Do not disturb it, and get it tested. White or grey tape and wrap on old duct joints in pre-1980 homes can contain asbestos. It is a risk when it is cut, sanded or crumbling.
If it tests positive and needs to come off for duct work, a qualified abatement contractor should remove it. Intact tape can often be left alone or sealed over. We do not disturb suspect material.
Why is my house so dusty even with a new filter?
A dusty house with a new filter usually means the dust gets around the filter. Leaky return ducts in a dusty basement, a filter that does not fit its slot, or gaps around the filter door pull in unfiltered air. Renovation dust and a dry house also add to it.
Seal the returns, use a filter that fits snugly, and add humidity in winter.
Why is my house humid in summer with the AC on?
A house that stays humid with the AC on often has an oversized AC that cools fast and shuts off before it removes moisture. A dirty coil, a fan set to on instead of auto, or a damp basement also add humidity. Set the fan to auto first.
A dehumidifier in the basement helps in many Detroit homes. If the AC is oversized, the long-term fix is a properly sized system.
The only way to get a real price for your home is an on-site visit and a written quote. Call or text (313) 488-2188.