FIRE RATED DUCT, GREASE DUCT AND 1 OR 2-HOUR VENTILATION AIR DUCTWORK

Section 15880
Section 15900 Air Distribution

Application of fire-rated thermal insulation

• Required for use on commercial kitchen grease ductwork or other ductwork such as emergency ventilation air ductwork as a gypsum shaft alternative.
• Material shall be applied directly to the ductwork in strict accordance with the listed system and manufacturerâs instructions.

Applicable Ductwork fire rating standards are:

• NFPA-96 – standard for Ventilation Control & Fire Protection for Cooking Operations
• ULC Standard for Grease Duct Testing
• ISO-6944 Duct “A” Standard with 1 or 2-hour external duct fire rating
• SLC-S115-95 – Firestop testing standard
• ULC-S102 for 25/50 Flame Spread & Smoke Development Rating

Acceptable Manufacturer’s Warnock Hersey design number CL4/FRD-PHV/120-01 installed as follows:

• Commercial kitchen grease ductwork or 2-hour external fire-rated emergency ventilation air ductwork requires the use of 2-layers of CL4FIRE soluble fibre thermal insulation installed with staggered butted seams per listed system instructions.
• 1-hour external fire-rated emergency ventilation air ductwork requires the use of 1-layer of CL4FIRE thermal insulation installed with 3" overlapping seams. Butted seams are not acceptable for 1-hour fire ratings.

All banding and weld-pins must be installed strictly per listing requirements.

• Support rods and anchors must be properly sized and spaced to match the duct size per listing requirements.
• All banding, anchors and support rods not matching the system requirements will be removed and replaced.

Inspection standards

• Sites must be reviewed with the manufacturers’ designated CL4FIRE thermal insulation representative prior to installation and at intervals during installation.
• Final installation must contain a letter of review by the CL4 Inc. designated representative.