Duct installation is the process of assembling and securing metal or flexible ducting to distribute conditioned air throughout a building. Ducts transport heated or cooled air from the equipment to individual rooms and return air back to the system. Proper duct installation requires precise measurements, sealing, insulation, and support to minimize air leakage and maintain system efficiency.
Technical Details
Ducts must be sized according to ACCA Manual D using friction loss calculations and velocity limits of 600 to 900 feet per minute in supply ducts. Sheet metal ducts require duct sealing with mastic or metal-backed tape to meet ASHRAE 52.2 leakage standards. All ducts should be insulated with R-6 minimum insulation in unconditioned spaces. Proper support spacing prevents sagging: rigid ducts require support every 4 feet, flexible ducts every 3 feet.
Practical Significance
Well-installed ducts reduce air leakage losses by maintaining seal integrity and prevent temperature stratification in long runs. Leaky ducts can waste 20 to 40 percent of system output. Proper installation improves comfort, efficiency, and indoor air quality.