Air Sealing and Testing Requirements
The 2018 IECC, adopted by Texas, requires comprehensive air sealing to reduce energy loss and prevent moisture issues.
To ensure compliance, homes must undergo:
✔ A visual air sealing inspection
✔ A post-construction blower door test
These requirements apply to all residential buildings and certain multifamily occupancies (R2, R3, R4).
Blower Door Testing Requirements in Texas
Texas mandates blower door testing for all new residential construction. This test measures Air Changes per Hour (ACH) at 50 Pascals (ACH50).
| Climate Zone | Max Air Leakage (ACH50) |
|---|---|
| Zone 2 (Southern TX) | ≤5 ACH50 |
| Zone 3 (Central TX) | ≤5 ACH50 |
| Zone 4 (Northern TX) | ≤3 ACH50 |
Note: Unlike other states that allow a visual inspection alternative, Texas requires actual blower door testing for compliance.
What is Air Changes per Hour (ACH)?
ACH measures how often the air inside a house is completely replaced with outdoor air within one hour.
Formula:
ACH = (CFM x 60) ÷ House Volume (cubic feet)
– CFM (Cubic Feet per Minute): Leakage rate measured by the blower door test
– House Volume: Total cubic feet of the house
Lower ACH values indicate better air sealing, leading to higher energy efficiency and lower heating/cooling costs.
Texas Air Sealing Requirement
To pass the blower door test, homes must follow strict air sealing guidelines, including:
✔ Sealing joints, gaps, and penetrations in walls, ceilings, and floors
✔ Weather-stripping doors and windows
✔ Caulking and sealing around plumbing, electrical, and HVAC openings
✔ Sealing ductwork connections to reduce leakage
For a complete checklist, refer to the [Texas Energy Code Air Sealing Guide].
Third-Party Testing Requirements in Texas
The 2018 IECC allows local code officials to require that blower door testing and air sealing inspections be conducted by an approved third party.
Certified professionals must be accredited by one of the following:
✅ BPI (Building Performance Institute)
✅ RESNET (Residential Energy Services Network)
Before scheduling an inspection, check with your local jurisdiction to confirm third-party testing requirements.
To schedule a blower door or duct leakage test in Texas, contact:
📞 888-213-3975 – Local Energy Audits
The 2018 IRC/IECC gives the local code official the option to require that air sealing inspections and blower door testing be completed by an “approved third party”
Approval of third parties is at the discretion of the local code official. In most cases, certification by one of the following organizations will be required:
Local Energy Services
can help you comply with the 2018 IRC/IECC Inspection and Testing Requirements
