🛑 UL 555 / UL 555S (Leakage Class I <4.0 CFM/sqft @ 250°F / 350°F High-Temp Rating)

Fire-Smoke Damper Leakage Calculator

Size motorized combination fire and smoke dampers (FSD) across fire-rated shaft barriers and demising walls under UL 555 & UL 555S: calculate leakage ratings (Class I < 4.0 CFM/sq ft @ 4.0" WC at 250°F or 350°F elevated temperature rating), size electric/pneumatic fail-safe spring actuators (<15 second closing speed), and commercial ductwork damper margins.

1. Project & Operating Inputs

Fire-Smoke Dampers Installed (Damper Count e.g. 64 Motorized Dampers)

Average Damper Face Area (Square Feet e.g. 6.0 Sq Ft Duct Cross-Section)

Customer Bid Price for Supplied, Mounted & Landed FSDs ($ / Damper)

Ruskin/Greenheck UL Class I Damper, Belimo 120V Actuator, Duct Armor & Tech ($)

2. Financial Breakdown & Yield

UL 555S FIRE-SMOKE DAMPERS

Turnkey Damper Installation Profit

Life Safety HVAC Damper Margin

0.0%

Gross Revenue / Bill

Total Project CapEx

Operating / Material Cost