On January 1st, 2011, with the
implementation of the new Energy Codes, Duct and Envelope Tightness (DET)
verification and testing became mandatory for all new residential building
permits issued on or after July 1st, 2011.
This is required for all new
residential construction. For complete code information refer to
2011 Georgia State Supplements and
a plus, inc. has 5 DET
Verifiers on staff to perform this testing. Contact us at 404-373-plus
(7587) or firstname.lastname@example.org
to schedule the testing.
Allowable Leakage Rates
Specifications for DET verifier
Allowable Leakage Rates:
In simple, general terms, the
maximum allowable leakage rates for the building envelope and for duct systems
that are outside the building envelope are shown below:
Blower Door Testing:
The building envelope must
achieve fewer than 7 air changes per hour at 50 Pascals (7 ACH50).
This test can only be done
Duct System Testing:
Duct system can be tested at
rough-in or post construction with the 'Total Leakage' test OR at post
construction with the 'Leakage to Outside' test.
Rough-In Total Leakage (RIT) must
be less than 6 CFM25 per 100 SF of conditioned floor area served by that
particular duct system.
Post-Construction Total Leakage
(PCT) must be less than 12 CFM25 per 100 SF of conditioned floor area served
by that particular duct system.
Post-Construction Leakage to
Outside (PCO) must be less than 8 CFM25 per 100 SF of conditioned floor area
served by that particular duct system.
Specifications for a DET
Testing for building envelope and
duct tightness shall be conducted by a certified DET verifier.
A certified DET verifier shall be:
A Building Performance Institute
(BPI) analyst; or
Successfully completed a
certified DET verifier course that is approved by the Georgia Department of
Community Affairs; or
A Certified Home Energy Rating
Systems (HERS) rater; or
A Certified Home Performance with
ENERGY STAR contractor.
The required envelope and duct
tightness testing is accomplished by using a blower door and duct blaster
pressure testing system.
The results of the envelope and
duct tightness test are required to be filled out by the DET Verifier on a permanent
certificate that is posted on or near the electric panel or air handler.
If the test fails, then nothing
is recorded until there is a successful retest.
The top portion of the
certificate is filled out by the builder, and the mechanical portion by the HVAC
Download a copy of the
Download a copy of the instructions
Residential buildings include:
One and two family dwellings
Multi-family apartment buildings
Residential care / assisted
living facilities (R-4) that are 3 stories or less in height above grade.