Does Your House Leak?

Lee Duerst • April 29, 2026

The Hidden Air Leaks in Your Home

In a previous post, we wrote about houses that are too tight, ventilating poorly and creating problems. A house that’s too tight holds everything in—including stale air and moisture.

Conversely, a house that’s too loose leaks air everywhere—your warmed air sneaks out during winter months and cooled air escapes in the summer.

Comfort is hard to maintain in either case.

When people think about making their home more comfortable, they usually think about insulation.

That makes sense.

But here’s the catch:

Insulation slows heat down.
Air leaks carry it away.

And air moves a lot faster than heat.

What Is an Air Leak?

An air leak is any gap, crack, or opening where air moves in or out of your house.

Not big holes. Not missing walls.

Small stuff:

  • Gaps around pipes and wires
  • Openings at the top of walls
  • Seams around attic hatches
  • Rim joists (box sills)
  • Around windows and doors

Individually? Not a big deal.
Together? It adds up fast.

Why Air Leaks Matter More Than You Think

1. They Steal Heat (and Your Money)

Warm air doesn’t just sit still—it rises and escapes.

When it does:

  • Cold air gets pulled in to replace it
  • Your heating system works harder
  • Your energy bills go up

You’re not just heating your house… you’re heating the outdoors.

2. They Make Rooms Feel Uneven

Ever notice:

  • One room is fine
  • Another is always cold

That’s often not insulation. It’s air movement.

Air leaks create:

  • Drafts
  • Cold floors
  • Temperature swings

3. They Bring in Outside Air From the Wrong Places

When air leaves, it has to be replaced.

The house doesn’t care where it comes from.

It might pull air from:

  • The attic
  • The basement
  • The garage

Not exactly the cleanest or most comfortable sources.

4. They Carry Moisture With Them

Air doesn’t move alone—it carries moisture.

That can lead to:

  • Condensation
  • Mold
  • Attic moisture problems

This is where “comfort issue” becomes “house problem.”

Where Air Leaks Usually Happen

This is the part most people never see.

Common trouble spots:

  • Attic floor (top plates, penetrations)
  • Box sills / rim joists
  • Around chimneys and flues
  • Recessed lights
  • Plumbing and electrical penetrations

These are the areas that make the biggest difference when sealed.

The Big Misunderstanding
“I need more insulation.”

Sometimes true.

But often:

The insulation is there—the air is just going around it.

What Actually Fixes the Problem?

Not just insulation.

👉 Air sealing first, insulation second

That means:

  • Sealing gaps and penetrations
  • Blocking airflow pathways
  • Then insulating to hold the heat in place

The Bottom Line

If your house feels:

  • Drafty
  • Uneven
  • Hard to keep comfortable

There’s a good chance air leakage is part of the problem.

And the fix isn’t always adding more insulation.

Sometimes it’s stopping the air from moving in the first place.

Call to Action

Not sure where your house is leaking?

That’s normal—you usually can’t see it.

But you can feel the results.

Reach out or send a few photos—we’ll help you figure out where the problem is and what’s worth fixing.

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