Insulation Without Air Sealing Is Half a Job.
Insulation slows heat transfer. Air sealing stops air movement. You need both. Most homes — even recently insulated ones — have significant air leakage through bypasses that insulation alone can't address.
What Is Air Sealing?
Air sealing is the process of identifying and closing the gaps, cracks, and penetrations in your building envelope that allow conditioned air to escape and outside air to enter. These bypasses are often invisible — hidden in attic floors, wall top plates, around plumbing and electrical penetrations, and at the rim joist.
Where Air Leaks Hide
Attic floor
Top plates, partition walls, and framing gaps are major bypass routes — often hidden under existing insulation.
Rim joist
The band of framing at the foundation level is one of the leakiest areas in most homes.
Recessed lights
Old-style recessed cans are essentially holes in your ceiling — each one leaks significant air.
Plumbing & electrical
Every pipe, wire, and duct that passes through the building envelope is a potential air leak.
Attic hatch
Uninsulated, unsealed attic hatches are a direct connection between conditioned and unconditioned space.
Knee walls
In cape-style homes, knee walls and the floors behind them are common bypass routes.
Our Air Sealing Process
Blower Door Diagnosis
We use a blower door test to measure total air leakage and, combined with thermal imaging, locate where the leaks are.
Attic Bypass Sealing
We seal top plates, partition walls, penetrations, recessed lights, and other attic bypasses using caulk, foam, and rigid blocking as appropriate.
Rim Joist Sealing
Rim joists are sealed and insulated using spray foam or rigid foam board, addressing one of the most common leakage points.
Verification Test
After sealing, we run a second blower door test to measure the improvement and document the before/after results.
Air Sealing + Insulation: The Complete Package
We air seal before adding insulation — not after. Sealing first means the insulation performs as intended. Adding insulation over unsealed bypasses is a waste of money. Attic insulation projects we do typically include air sealing as a standard part of the scope.
Stop Paying to Heat the Outdoors
Air sealing is the most cost-effective energy upgrade most homes can make. We'll assess your home, identify the leaks, and give you a straight estimate.