Most homeowners never think twice about their ductwork. It’s hidden behind walls, under floors, or up in the attic—out of sight, out of mind.
But here’s the truth: your duct system could be costing you hundreds of dollars every year in wasted energy and poor comfort. And unless it’s been tested, you’ll never know for sure.
That’s where a duct blast test comes in.
What Is a Duct Blast Test?
A duct blast is a pressure test designed to find air leaks in your duct system.
We seal off the registers and force air through the ducts using a calibrated fan. By measuring how much air escapes, we can determine how leaky your ductwork is.
The test gives us a measurable leakage rate—kind of like a report card for your system’s ability to hold air.
Why Duct Leaks Matter
Even small leaks can add up to big losses. According to ENERGY STAR, the typical duct system loses 20% to 30% of the air it moves. In some homes, we’ve seen it closer to 40% or more.
Think about that: for every $100 you spend heating or cooling your home, $20 to $30 could be escaping into your attic, crawlspace, or walls.
And that air doesn’t just disappear—it pulls in dirty, unconditioned air from those same areas back into your home, affecting air quality and comfort.
How Leaky Ducts Affect Your System
Leaks in the duct system can cause a variety of performance issues:
- Uneven temperatures in different rooms
- Long run times or short cycling
- Higher energy bills
- More wear and tear on equipment
- Excess dust, allergens, or humidity in your home
In short, your HVAC system works harder and less effectively when the ducts aren’t sealed tight.
How We Use Duct Testing at Northwest HVAC
At Northwest HVAC, we use duct blast testing as a tool—not a scare tactic.
If your system is underperforming or your utility bills seem too high, this test helps us get to the root of the issue. We may recommend it when:
- You’re replacing equipment in an older home
- You have hot and cold spots we can’t explain with equipment alone
- You’re considering duct sealing or insulation
- You want to verify energy efficiency improvements
We also use test results to inform our design decisions when sizing new equipment or reworking duct layouts.
Can Duct Sealing Really Make That Much Difference?
Yes—especially if you have a leaky system.
Properly sealed and tested ductwork can:
- Improve airflow to every room
- Lower your energy bills
- Help your HVAC system run quieter and last longer
- Improve indoor air quality
It’s one of the most cost-effective upgrades we can recommend.
Don’t Let Your Ducts Steal Your Comfort
Your ductwork is the delivery system for all the heating and cooling you pay for. If it’s leaking, you’re not getting what you paid for.
Duct testing helps you understand what’s really going on behind the scenes—and what it will take to fix it.
At Northwest HVAC, we believe good comfort starts with good airflow. And good airflow starts with a duct system that actually works.
Let’s find out what your ducts are doing when you’re not looking.
About Northwest HVAC Service
Northwest HVAC Service is a family-owned business proudly serving Vancouver, WA and surrounding communities since 1998. We specialize in residential retrofit HVAC systems, including ductless upgrades, electric heat pumps, airflow redesign, and comfort diagnostics. Whether you’re replacing outdated equipment or trying to fix long-standing comfort issues, we bring honest advice, expert service, and long-term solutions you can trust.