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A furnace that’s the right size is one you stop thinking about. Getting there in Holliston takes more care than it sounds, because the town doesn’t have one kind of house. The median home dates to about 1966, roughly 18% were built before 1940, and the 2016 and 2017 colonials in town run 3,600 to 4,200 square feet.
That spread is why “same size as the old one” is a risky way to approach furnace replacement in Holliston. A 1964 raised ranch in the Brentwood neighborhood that has picked up new windows and extra insulation usually needs less heat than its original furnace was sized for. A 2017 colonial in Fafard’s Constitution Village needs its load measured, not guessed from square footage. Miss in either direction and you get a furnace that short-cycles, burns more fuel than it should, and still leaves a back bedroom cold.
Done right, new furnace installation in Holliston gives you even heat through a cold season that runs from early December to mid-March, with January averaging a 36°F high and a 20°F low. Your system runs in steadier cycles instead of constant starts and stops. About 87% of Holliston homes are owner-occupied, so most people making this call will live with the result for the 15 to 20 years a furnace typically lasts. It’s worth getting the size right the first time.
Dempsey Energy is a residential heating, cooling, and plumbing company that has worked with more than 12,000 customers. For heating system installation in Holliston, MA, a town in the MetroWest part of Middlesex County, we send a technician who looks at the house in front of them. It could be a historic home on Washington Street or a 1960s ranch.
Heating and plumbing sit under one roof here, which matters in older Holliston homes where the boiler, water heater, and gas line often share a mechanical room. You won’t get passed between companies to sort out an overlap.
We’ll tell you when a repair makes more sense than replacing, and we explain the scope behind any estimate before work starts. After the install, we follow up. The Dempsey Comfort Club is there for tune-ups and priority scheduling, and our attention doesn’t end when the crew drives away.
It starts at your house. We measure the space, look over your ductwork, and size the furnace to what the home needs, with no guessing or shortcuts. You get a written estimate with the scope spelled out, including any venting, gas line, or duct changes, since those are what move the price in older homes.
Next is the paperwork. Holliston’s Building Department sits in the basement of Town Hall at 703 Washington Street, and it requires applications to be paid for before they enter review. The plumbing and gas inspector also keeps limited office hours. We pull the permits your job calls for and schedule the municipal inspection, so you aren’t the one standing in line or working around the inspector’s calendar.
On install day, which usually runs four to eight hours, the crew protects your floors and belongings, removes and hauls away the old system, and makes any electrical or gas line changes. The new furnace gets set to manufacturer specs and Massachusetts codes. Then comes testing: safety systems, gas connections checked for leaks, airflow verified, thermostat set up. You get warranty information and operating instructions before the crew leaves. For furnace installation in Holliston, early fall or spring gives you time to compare quotes before the cold season begins in early December.
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A furnace job covers more than the furnace. Your scope includes the home assessment and sizing, permits and inspections, removal of the old unit, any electrical or gas line modifications, installation to manufacturer specs, and full testing. Installs come with warranty protection on both the equipment and the installation work. We stand behind the workmanship, and the manufacturer stands behind the equipment.
Older houses are where the details matter. Homes from the historic district along Washington Street to the 1960s ranches have had decades of additions, window swaps, and equipment changes. Existing ductwork, venting, and gas lines get a real look instead of being assumed fine.
If gas is available on your street, gas furnace installation in Holliston is worth discussing. If you’re weighing a furnace against a heat pump, that comes up during the assessment too. Your furnace installation cost in Holliston depends on those answers, which is why the estimate comes after we’ve seen the house.
Once the install is done, the Dempsey Comfort Club gives members scheduled maintenance, annual tune-ups, priority scheduling, and discounts on repairs. We also handle the plumbing side, so a boiler or water heater question in the same mechanical room doesn’t mean calling a second company.
Yes. Furnace work in Massachusetts generally needs a permit and an inspection, and gas work has to be permitted by a licensed master gas fitter. That’s why this isn’t a job for a handyman. In Holliston, permits go through the Building Department in the basement of Town Hall at 703 Washington Street. The town lists separate gas, plumbing, and sheet metal applications, and which ones your job needs depends on what’s being changed.
Applications go through the town’s online portal and have to be paid for before they enter the review queue. The plumbing and gas inspector keeps limited office hours. That’s the part that catches homeowners off guard when they try to manage it themselves. When we do the work, we handle the paperwork and schedule the municipal inspection, so you end up with a sign-off instead of a to-do list.
We don’t post flat prices, because the number depends on your house, but typical ranges help you sanity-check any quote. Massachusetts-wide, cost guides put replacing a furnace at about $4,300 to $8,850. Angi’s Boston data lists an average of $6,396, with most homeowners paying between $3,730 and $9,077. Treat those as typical ranges, not a Dempsey Energy quote.
Your furnace installation cost in Holliston will move with the heating load of the house, fuel type, efficiency rating, ductwork condition, any venting or gas line changes, permits, and removal of the old unit. In Holliston that range is easy to see. A 1,500 to 2,000 square foot ranch and a 4,000 square foot colonial are different jobs, and ductwork in an older home may need more attention than in a 2017 build. After an in-home assessment you get a written estimate with the scope spelled out, so you can compare two or three quotes side by side.
Most installs take about four to eight hours, so for a standard swap you’re usually warm again the same day. Longer jobs tend to involve ductwork or venting changes or a gas line modification, which is another reason the assessment comes first.
On the day, the crew lays down protection for floors and belongings, removes and hauls away the old furnace, makes any electrical or gas line changes, and sets the new unit to manufacturer specs. Then we test the safety systems, check gas connections for leaks, verify airflow, and set up the thermostat. The town inspection gets scheduled as part of the job.
Holliston’s cold season runs from about December 2 to March 13, so the smoothest furnace replacement in Holliston is one you schedule before the first hard cold, or in spring when you have time to compare quotes. If your furnace has already quit, tell us when you call so the scheduling reflects that.
It depends on what’s wrong more than on age alone. Gas furnaces typically last 15 to 20 years, and after about year ten they lose roughly 1 to 2% of their efficiency each year. The general advice is that repair is usually the better value unless a major part, like the heat exchanger or control module, fails. That’s especially true on a unit past 15 years.
So if your furnace is under 15 and the problem is a minor part, repair is probably the right call, and we’ll tell you that. If it’s older, breaking down more often, or the heat exchanger is the issue, replacing starts to make sense.
With a median build year around 1966, plenty of Holliston houses have had new windows, insulation, or additions since the current furnace was sized. Replacing it can also be a chance to size the system to the house as it is today.
Standard furnaces start around 80% AFUE. The federal minimum for new gas furnaces is 78%, and high-efficiency models reach 95 to 98%. ENERGY STAR certified furnaces are up to 15% more efficient than baseline. Whether the step up pays off depends on the house and how hard the system runs, so we won’t hand you a savings number we can’t back up.
Holliston has a long heating season and plenty of larger homes, so the question is worth asking. Mass Save says heating and cooling together make up more than half of average home energy use. Mass Save incentives change, so ask us about current ones instead of relying on an old article. The federal 25C tax credit expired on December 31, 2025.
If you’re also weighing a heat pump, bring that up during the assessment. The town held a Climate Action Plan update and Q&A in March 2026, so you’re not the only one asking.
The Dempsey Comfort Club is our membership program. It includes scheduled maintenance, annual tune-ups, priority scheduling, and discounts on repairs. We don’t publish a price or tier levels on the site, so ask for current terms when you’re getting your estimate.
Is it worth it? Holliston’s furnace season runs from roughly early December to mid-March, and the first cold snap is when everyone calls at once. Priority scheduling matters most then. An annual tune-up also gives a technician a look at your venting, gas connections, and ductwork every year. That counts in houses that have been modified over decades.
If your furnace is brand new, you may not need repairs for a while, and the tune-ups are the main draw. If you’re keeping an older system running, the repair discounts are what you’d use. We offer it at handover, and you’re free to say no.
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