Constructions Standards Checklists

SHEET METAL

HVAC SYSTEMS  A. All ductwork follows the design layout with fttings in the appropriate locations.  B. Balancing dampers are in place and are labeled and accessible per the layout drawing. Damper grilles are an acceptable method for dampening.  C. Longitudinal joints are correctly oriented in a downward fashion for proper sealing.  D. All seams in metal elbows and collar fttings are sealed with mastic or UL 181 tape, all longitudinal seams and transverse seams in branches and trunks are sealed with mastic or UL 181 tape.  E. Mastic is applied heavy enough to completely fll and cover seams at approximately 1/8" in thickness. (not pictured)  F. Metal boots are sealed with mastic or UL 181 tape to prevent leakage.  G. All seams in the duct insulation are sealed with mastic or UL 181 tape, leaving no gaps or openings at the ends where branches meet trunk lines, unions, or boots.  H. All plenums are sealed with mastic or UL 181 tape to air handler.  I. All living spaces have a return air strategy. Any

room requiring more than 50 CFM's of supply air will require return air strategy (dedicated return, jump duct, or transfer grille - no door undercuts except for closets, pantries or similar small spaces).  J. Sheet metal ductwork is secured and supported at proper intervals (2' from elbow, 4' from branch intersection, 8' straight run), and seams are all accessible for sealing (not pictured).  K. Ducts have a minimum R-10 rigid insulation installed behind if in exterior wall (i.e. garage).

 L. Branch takeoffs are installed more than 12" from trunk end.  M. Diffusers are placed as to not become blocked (not pictured).

CONSTRUCTION STANDARDS CHECKLISTS | HVAC Systems | 21