Blower door testing in Coralville, IA
Coralville’s housing mix is unusually varied — mid-century ranches along Fifth Street, 1980s and ’90s builds through the Clear Creek area, and a steady stream of newer construction near Iowa River Landing and the Coral Ridge corridor. Each age bracket tends to fail in its own way under a blower door test, and that’s exactly what the test is designed to reveal.
What a blower door test does
A blower door is a calibrated fan that mounts in an exterior doorway and depressurizes the house to 50 pascals below outdoor pressure. The fan measures, in real time, how much air your home is leaking. That number — expressed as CFM50 or converted to air changes per hour (ACH50) — is the single most useful diagnostic figure in residential building performance.
For context, Iowa’s 2012 energy code requires new construction to test at or below 4.0 ACH50. Home Star Iowa typically targets 3.0 ACH50 as a reasonable performance goal for both new builds and retrofits. Older Coralville homes often come in at 8.0, 10.0, or higher — which translates directly to drafty rooms, inflated utility bills, and moisture problems that can damage the building itself.
Common Coralville problems
A few issues show up repeatedly in homes throughout Coralville:
Lower-level heat loss
Homes with walk-out basements or daylight lower levels near Iowa River Landing frequently show significant rim joist and sill plate leakage. These areas are almost never sealed well during original construction.
Moisture pressure
Pressure imbalances pull humid outdoor air — or worse, humid crawlspace air — into conditioned space. A damp basement smell is often the first warning sign.
Attic bypass leakage
Plumbing chases, electrical penetrations, dropped soffits, and top plates are the usual suspects. Infrared imaging during the blower door test makes these bypasses visible, often dramatically.
Duct leakage
In homes with ducts routed through attics or crawlspaces, leaky duct runs can undermine even a well-insulated envelope.
What happens during the appointment
A typical Coralville blower door appointment runs about two hours on site and follows a consistent sequence:
Pre-Test Walkthrough
We review the home to identify major envelope components and any safety concerns.
Fan Installation
The calibrated fan mounts in an exterior door with all other exterior openings closed.
Depressurization
The house is pulled to 50 pascals while we measure CFM and walk the building with infrared and smoke.
Diagnostic Imaging
We locate and document specific leakage sites — the exact spots where your house is losing air.
Thermal imaging →Report Delivery
A written report with prioritized recommendations, usually within a few business days.
Not Much to Do
Close windows and exterior doors, open interior doors, and make sure nothing is actively burning — fireplaces, wood stoves, and candles all need to be cold.
Serving Coralville and the Iowa City corridor
BPI-certified testing across the corridor:
A few things Coralville homeowners ask
Why does my basement feel damp?
Can I watch the test?
Will the test damage anything?
Do new homes in Coralville need a blower door test?
Schedule Coralville blower door testing
Independent, BPI-certified testing across Coralville and the Iowa City corridor. Every assessment is conducted personally, not subcontracted.