A home energy audit runs in a fixed order: a conversation about what's wrong, a walkthrough of the house, four measurements while the house is deliberately depressurized, then a written report ranked by what pays back first. None of it is mysterious, and none of it is a sales pitch dressed up as science. Novus Mechanical runs this audit for homeowners across Freehold, Marlboro, Manalapan, Colts Neck, Holmdel, Howell, and Millstone, all in Climate Zone 4A, and knowing the sequence ahead of time is most of what people want.
Before a technician pulls into the driveway, there's a short conversation: which rooms run hot in July and cold in January, what the bills have been doing lately, and whether that number surprised anyone. What's already been replaced: a new furnace five years ago, a heat pump added last summer, new windows on one side of the house but not the other.
That conversation shapes the visit. A house with one starving bedroom upstairs gets a closer look at the duct runs feeding it; a house with brand-new equipment but bills that never dropped gets a closer look at the envelope instead. None of it is small talk. Ten minutes on the phone saves an hour on site.
The walkthrough comes next: mostly eyes and a flashlight before any equipment gets set up. What we check:
In the 1960s and 1970s ranches and split levels across Freehold Township and Howell, this is usually where the story starts: one equipment swap since they were built, but the ducts, attic insulation, and rim joist are original. Marlboro and Colts Neck run a different pattern, newer and larger homes with long duct runs where the farthest bedroom never catches up. In Manalapan's 55+ communities, everything sits on one level, which simplifies the duct picture but changes nothing about insulation and air sealing.
Once the walkthrough is done, we seal a calibrated fan into the front door frame. That's the blower door test, the first measurement taken while the house is deliberately depressurized. The fan pulls air out until the house hits 50 pascals, roughly a steady 20 mph wind on every side of the house at once. Two numbers come out: CFM50, the raw airflow in cubic feet per minute leaking back in, and ACH50, that number divided by house volume so a small ranch and a big colonial compare fairly. Lower is better on both, and an older house here reading high is normal for its age, not a sign anything was done wrong.
That's also when the infrared camera comes out. While the fan runs and the house stays depressurized, air pulls through every gap, and thermal imaging catches the temperature difference as it moves past insulation, framing, and trim. The same camera on a house that isn't depressurized misses most of it; mid-test, missing insulation, an unsealed can light, or a gap around a window frame shows up as a clear streak. That's why thermal imaging happens during the blower door test, not as its own visit.
Duct leakage gets tested separately: a tight envelope and a leaky duct system are two different problems with two different fixes. We pressurize the ducts and measure how much air escapes before it reaches a supply register. In the longer duct runs common to Marlboro and Colts Neck developments, this is often where a far bedroom's comfort problem actually lives, not the equipment. Read more on duct leakage testing.
On any home with gas or oil equipment, we also run combustion safety and carbon monoxide checks: flue draft, backdrafting, whether the appliance vents properly. This matters most on older standing pilot furnaces and water heaters still running in Freehold Borough, and it isn't optional. A house sealed tighter without this check is one where a marginal flue turns into a real problem. The EPA recommends a CO alarm on every level of the house, and we check for that too.
The report ranks findings by what pays back first, not by the order the tests ran in. Major leakage puts air sealing at the top, and in a Radon Zone 1 county that sealing gets coordinated with radon mitigation, not done blind. Significant duct loss puts duct sealing next. Close to a replacement, the Manual J load calculation behind that decision comes from the same visit and shapes the size of whatever gets installed. Photos and thermal images back up each item, so you're not taking anyone's word for it, and you own the report either way.
Cost depends on which tests the house needs. A blower door test starts at $350, a load calculation starts at $350, and duct testing and thermal imaging add to that by size and layout, priced before anything starts. Timing decides the payoff: get it done before replacing a furnace, AC, or heat pump, and the results change the size of the equipment you buy. Book it as a standalone curiosity with no project attached, and it's worth a lot less, even though the numbers are still true.
A fair amount of the walkthrough you can do yourself. Check attic insulation depth against the joists, feel around the attic hatch and rim joist for a draft, and look at windows for daylight around the frame. ENERGY STAR lays out what a full home performance assessment covers, which is a useful checklist to walk your own house against first. What you can't do is measure: you can feel a room is drafty, but not put a number on the leakage rate, the duct loss, or whether a furnace vents safely, and a humid Monmouth County summer makes that dehumidification number matter as much as the heating bill.
| Step | What it checks | Can you do it yourself? |
|---|---|---|
| Visual walkthrough | Insulation depth, window condition, attic hatch, obvious drafts | Yes, largely |
| Blower door test | Total air leakage, reported as ACH50 and CFM50 | No, needs a calibrated fan and gauge |
| Thermal imaging | Exactly where the leaks and missing insulation are | Only roughly, with a phone add-on camera |
| Duct leakage testing | How much conditioned air the ducts lose before reaching a room | No |
| Combustion safety / CO check | Whether gas or oil equipment is venting safely | No |
Novus runs home energy audits, residential only, for homeowners in Freehold, Marlboro, Manalapan, Colts Neck, Holmdel, Howell, Millstone, and the surrounding parts of Monmouth County. Appointments run Monday through Friday, 8 AM to 6 PM, and the phone is answered any time so you can get on the schedule.
Whether you want the full home energy audit or just the blower door test first, Schedule My Appointment and we'll walk you through which tests your house needs before you pay for any of them.
Pricing starts at $350 for a blower door test and $350 for a load calculation, with duct testing and thermal imaging added as needed, priced before anything starts. You can do a real amount of the visual walkthrough yourself using the DOE's DIY guide. What you can't do is measure: air leakage, duct loss, and combustion safety all require calibrated equipment.
Clear access to the mechanical room, the attic hatch, and the electrical panel, and make sure we can reach every room including closets on exterior walls. Have a year of gas and electric bills handy if you can, since usage history tells us a lot before we measure anything. Plan for the house to be closed up during the blower door test, so no fireplace in use that morning, and pets somewhere comfortable away from the front door.
Two to four hours for a typical single family home. The blower door setup and test is about an hour of that, thermal imaging and duct testing add another hour or so, and the rest is the walkthrough and the combustion safety checks. Larger homes, multiple systems, or difficult attic access push it longer. The written report comes afterward rather than the same day.
It is worth it when you are about to spend real money on the house: replacing equipment, adding insulation, or fixing rooms that have never been comfortable. The measurements keep you from buying the wrong size system, or insulating over leaks that needed sealing first, and either mistake costs more than the audit did. It is not worth it if you have no intention of acting on what it finds.
We measure your home, explain what we find, and hand you one clear price. Book a consultation in Freehold or Monmouth County.
Updated August 2026 by Novus Mechanical, Freehold, NJ
