Insulation is a winter coat. Air sealing is zipping it up. This is the step most Houston attic jobs skip, and it is the reason so many homeowners pay for new insulation and feel no difference.
Hot attic air pours down through them in summer. Conditioned air escapes up through them year round. Blowing fourteen inches of insulation on top does almost nothing about it, because air moves straight through loose-fill material.
A very good coat left hanging open does not keep you warm, and no amount of a thicker coat fixes an open zipper.
Where interior walls meet the attic there is a gap running along the top of every wall in your house. Added up it is often the single largest air pathway in the building, and the most commonly skipped, because sealing it means crawling the perimeter of every wall.
Older fixtures are essentially open holes into your ceiling, and there can be dozens. Some are rated to be covered with insulation and some absolutely are not, which is a fire issue, not just an efficiency one.
Every vent stack and supply line leaves a gap around it. Plumbers are not paid to seal them.
Wiring runs, junction boxes, and holes drilled through framing for cable. Individually small, collectively significant.
Usually thin plywood in a frame with no weatherstripping and no insulation on top. A hole in your ceiling that you open on purpose. Cheap to fix and immediately noticeable in the room below.
Two problems at once. The gap around the housing leaks, and we regularly find fans venting into the attic instead of out through the roof, pumping humid air into an enclosed space in a city that needs no help with humidity.
Fire-rated materials with proper clearance, never spray foam. The one place on this list where the wrong fix is genuinely dangerous.
The boxed-out areas above kitchen cabinets and bathrooms. From the attic they are open cavities dropping straight into your ceiling. Almost nobody seals these.
Where ductwork meets the ceiling. Leaks here waste air you already paid to cool, which is the most expensive air in the house.
You cannot seal what you cannot see, which is why an air sealing job usually starts with clearing the attic floor. Anyone who tells you they will seal after blowing is not sealing.
You are paying for work that gets covered up an hour later, so protect yourself.
Insulation slows heat moving through a surface. Air sealing stops air moving through a hole. They solve different problems and neither substitutes for the other. Loose-fill insulation does very little about air pouring through an unsealed can light, because air moves straight through it.
Nine times out of ten the sealing step was skipped. The biggest heat pathway in the ceiling was never touched, it was buried. This is the single most common complaint we hear about a previous contractor.
Wall top plates, recessed can lights, plumbing penetrations, electrical bypasses, the attic hatch, bath and kitchen exhaust fans, chimney and flue chases, dropped soffits above cabinets, and duct boots at the ceiling.
It should not, and this matters. Soffit vents and ridge vents are supposed to stay open. Attics need airflow above the insulation, and in Houston humidity, blocking ventilation creates a moisture problem. Proper installs use baffles at the eaves to hold insulation back.
Utility efficiency programs are built around measured energy savings, which is why they pair insulation with air sealing rather than treating them separately. Program terms change annually, so confirm current requirements directly with your utility.
We will show you exactly where your attic is leaking.