Infiltration and Duct Leakage (IDL) Certification and Training

The BPI IDL certification is designed to provide a national credential documenting an individual’s ability to perform building envelope (infiltration) and duct leakage testing to verify compliance with IECC envelope and duct tightness requirements.  While BPI IDL certification is not specifically required to test homes for IECC compliance, achieving BPI IDL certification verifies an individual can conduct duct leakage and blower door tests to the ASTM E1554-07 standard.  Training is recommended (but not required) to achieve BPI IDL certification.  Click here for more information about the BPI IDL certification.

The Southface Duct and Envelope Tightness (DET) Verifier training prepares students to successfully challenge the BPI IDL certification exam.  Please note that BPI IDL exams are NOT included with the DET Verifier training and may be scheduled separately for an additional fee of $250.00.  Note that successful completion of the Southface DET Verifier training (and passing the associated Southface written and field exams) also documents an individual’s qualifications to perform duct and envelope tightness testing to verify compliance with IECC requirements, regardless of BPI IDL certification.

To register or schedule an exam, please contact


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Mon 28

BPI Manufactured Housing Professional

August 28 @ 9:00 am - August 30 @ 5:00 pm
Sep 06

BPI Home Energy Professional Quality Control Inspector Refresher

September 6 @ 9:00 am - September 7 @ 5:00 pm
Sep 13

Duct & Envelope Tightness Verification

September 13 @ 9:00 am - September 14 @ 5:00 pm
Nov 08

Duct & Envelope Tightness Verification

November 8 @ 9:00 am - November 9 @ 5:00 pm

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