DALC 2.1

DALC stands for the HVAC Duct Air Leakage Class, which is a standard for measuring the air leakage in HVAC ductwork.

DALC was developed by the Sheet Metal and Air Conditioning Contractors' National Association (SMACNA).

DALC is important because it helps ensure that HVAC systems are properly sealed to prevent energy loss and maintain indoor air quality.

DALC has four classes: A, B, C, and D, with Class A having the lowest allowable air leakage rate and Class D having the highest.

DALC is determined through testing procedures outlined in SMACNA's HVAC Air Duct Leakage Test Manual.

Failure to meet DALC requirements can result in increased energy costs, decreased system efficiency, and potential indoor air quality issues.

Yes, existing HVAC systems can be retrofitted to improve their DALC by sealing leaks and ensuring proper duct insulation.

While DALC is not a mandatory standard in all regions, it is recognized as a best practice for achieving energy efficiency and indoor air quality.