After undergoing considerable stakeholder input and review RESNET and the International Code Council (ICC) have completed work on the development of the RESNET/ICC 380-2016 “Standard for Testing Air Tightness of Building Enclosures, Air Tightness of Heating and Cooling Air Distribution Systems and Air Flow of Mechanical Ventilation Systems”. The Standard has been accepted by the American National Standard Institute (ANSI) as an approved American National Standard (ANS). ANSI signifies that the procedures used by the standards body in connection with the development of an ANS meets essential requirements for openness, balance, consensus and due process. Standard 380 was developed by RESNET and ICC to provide a consensus national standard for a consistent, uniform methodology for evaluating the airtightness of building envelopes and heating and cooling air ducts and the air flows of mechanical ventilation systems. These test procedures can be used as building diagnostics, in quality assurance and control, for determining compliance with codes and standards and to determine input to energy simulations and ratings. The RESNET/ICC standard recognizes that some test procedures are easier to perform depending on house and HVAC system characteristics and that different codes and standards have specific testing requirements. Therefore, the 380 standard presents several alternative approaches for each measurement to allow flexibility in application of the standard. The RESNET/ANSI standard recognizes ASTM E779-10 tests but expands the test methodology to allow single point tests under only one pressurization/depressurization condition and includes correction factors to account for test bias and uncertainty. This means that the 380 standard can be a substantially less expensive protocol than E 779. To view the new ANSI standard go to ANSI/RESNET/ICC Standard 380 – 2016 RESNET has proposed that the new RESNET/ICC standard be incorporated by reference into the 2018 International Energy Conservation Code (IECC). Section R403.3.3 of the IECC currently provides no guidance for testing duct systems to determine if they meet the maximum duct leakage rate. The current code language sets a duct leakage metric and essentially leaves it up to those that are testing the system to determine how to arrive at the results. The lack of guidance can lead to inconsistent test results from house to house. This code change proposal solves this problem by requiring testing to conform to RESNET/ICC Standard 380. This standard provides a standardized methodology that is currently in use throughout the industry. The methodology will provide consistent results that can be replicated by testing organizations and enforcement personnel. Section R402.4.1.2 of the IECC currently requires ASTM E779-10 as the method for conducting envelope air leakage testing. The E 779 standard requires multi-point testing under both pressurized and depressurized conditions. The RESNET/ICC standard allows for multiple test procedures to provide flexibility for the testing industry. Standard 380 also covers testing for single-family and 3-story and less multi-family projects and will be referenced as the protocol for testing for the rating industry. RESNET/ICC 380-2016 allows E 779 tests but expands the test methodology to allow single point tests under only one pressurization/depressurization condition and includes correction factors to account for test bias and uncertainty. Thus, standard 380 can be a substantially less expensive protocol.
