Fire-stopping Intrumescents and Mortar

Ish—Intumescent fire-stopping, used to seal off floor & wall penetrations, qualifies under IEQc4.1 as an Architectural Sealant. However, intumescent paint falls under IEQc4.2.

Intumescent paint is usually applied to steel as fireproofing. When exposed to extreme heat, the paint expands, puffing up like popcorn, to form a protective insulating jacket around the steel. Since it is applied to steel, it may also have anti-corrosive properties. If it does, the Green Seal GC-03 VOC limit applies. Otherwise, use the GS-11 limits for “flat” or “non-flat.”

Ish—If the mortar is a mineral-based, cementitious product, with no organic binders, polymers, or additives, neither IEQc4.1 nor IEQc4.2 applies to it. Check material safety data or ingredient lists to verify the mortar’s composition. If it contains only inert mineral components such as gypsum, Portland cement, or microsilica, VOCs should not be a concern.

If the mortar does include organic components, it may qualify as a “Pigmented Fire-Retardant Coating” if it meets that definition in SCAQMD-1113-2004.

The SCAQMD has sometimes baffled me with their categories, and in this case, the lack thereof. In 2007 the fire-retardant coating category was eliminated. It appears that sometime between then and 2014 it was reinstated as "fire-proof coatings", into which intumescent paint would seem to fit. The 2014 limit for fire-proof coatings is 150 g/l. Prior to that it was 350 g/l. I haven't delved into when it was re-instated. If the product you are reviewing is under 150, you are OK either under the current SCAQMD category or the non-flat paint category. If you are above that , you may need to have discussion with the USGBC about if and how you could use the 350 g/l limit.

Keith—For LEED NC-2009, refer only to the versions of SCAQMD and Green Seal Standards referenced by credit requirements (GS-11-1993, GC-03-1997, & SCAQMD-1113-2004). Definitions and requirements have changed in newer versions of these standards. Ignore them. They are not relevant to LEED NC-2009.

Ish—How is the mortar applied? Is it spread across a surface like paint, or is it troweled in to fill a wall or floor opening. If it is used as a fill gaps, it is not a coating governed by IEQc4.2. It may fall under IEQc4.1, but only if it contains organic binders, polymers, or additive. If it is entirely mineral-based, it is just mortar, and neither IEQc4.1 nor IEQc4.2 applies.