Blower Door Test in Charlottesville, VA
A blower door test measures how airtight your home is and helps pinpoint where outside air is leaking in. Zephyr Environmental Solutions provides blower door testing for Charlottesville homeowners and builders who need clear results, documentation, and practical next steps.
What a blower door test measures
Airtightness, quantified with a simple pressure test
A blower door test uses a calibrated fan mounted in an exterior doorway to depressurize the home and measure how much air leaks in from outside. The result is typically expressed as ACH50, which reflects air changes per hour at a standard test pressure. Lower numbers indicate a tighter building shell, which usually supports better efficiency and more predictable comfort. For homeowners, it turns drafts into measurable data; for builders, it supports code-related verification and closeout.
What to expect during the test
Straightforward setup, clear readings, and a quick walkthrough
The test process is simple and non-destructive, and most homes are tested efficiently with minimal disruption. We set up the blower door, take readings, and, when helpful, use tools to help locate leakage pathways while the home is under pressure. A typical visit includes:
- Basic home setup (windows/doors positioned appropriately, interior doors opened)
- Fan setup and calibrated readings to capture airtightness results
- Leak-spotting walkthrough to identify common draft locations
- Clear explanation of what the number means and what to do next
Homeowner vs. builder uses, compared
Same test, different goals and deliverable
Blower door testing can serve different needs depending on whether you’re improving an existing home or finishing a new build. Use the chart below to see the typical goals and outcomes, and we’ll tailor the visit accordingly. Builders often need fast scheduling and documentation; homeowners usually want leak locations and an improvement roadmap. Either way, the value is clarity you can act on.
| Option | Best For | Primary Goal | Typical Outcome |
|---|---|---|---|
| Homeowners (comfort) | Drafty rooms, uneven temps, high bills | Find leakage pathways | Prioritized air sealing plan |
| Homeowners (verification) | After DIY or contractor air sealing | Measure improvement | Before/after ACH50 comparison |
| Builders/GCs (code) | New construction closeout | Document airtightness | Report for inspection/records |
| Builders (pre-check) | Before final inspection | Catch issues early | Fix leaks before official test |
“Too tight” concerns and ventilation
Controlled fresh air is better than random leaks
It’s common to worry that tightening a home could create indoor air issues, but the real goal is controlled ventilation, not uncontrolled leakage. A leaky home brings in outside air through random gaps, which can carry dust, humidity, and allergens. If a home is very tight, adding the right ventilation strategy can keep air fresh while protecting efficiency. We help you understand where your home sits on the spectrum and what practical next step makes sense.
Blower door testing FAQs
Answers for Charlottesville homeowners and builders
Who does blower door tests in Charlottesville?
Blower door tests are typically performed by home performance professionals and HVAC/testing specialists with calibrated equipment. The key is choosing a provider who can run the test correctly and explain results in a useful way. Builders also want documentation that is clearly presented for project records. Homeowners usually benefit most when the provider also helps identify where leaks are coming from, not just the number.
What is a blower door test and how is it done?
A blower door fan is installed in an exterior doorway and used to depressurize the home to a standard pressure. Instruments measure airflow needed to maintain that pressure, which correlates to how leaky the building shell is. While the fan is running, leakage pathways become easier to detect around common problem areas. The result is an airtightness metric you can use as a baseline or for verification.
Do I need a blower door test for Virginia energy code?
Builders often schedule blower door testing to support code-related energy verification and project closeout needs. Specific thresholds and requirements can vary by project and jurisdiction, so it’s important to confirm what applies to your build. The benefit of scheduling early is avoiding last-minute surprises that delay inspections. We can also help you understand the results and identify likely leakage areas if you’re close to the target.
How long does a blower door test take?
Most tests can be completed efficiently, though timing depends on home size and whether you want an in-depth leak-spotting walkthrough. The core test setup and readings are typically straightforward. If the goal is education and leak identification, we may spend additional time walking the home under pressure to point out key areas. You’ll know what to expect before the appointment.
What should I do after I get my blower door results?
The best next step depends on what the results show and what your goals are, comfort, efficiency, or compliance. If the home is leakier than expected, targeted air sealing is usually the most effective first move. If the home is already tight, you may focus on controlled ventilation and moisture management. We’ll explain practical options based on your results so the next step is clear.