3.1403.1 Air Seal Concrete Floor Slab Foundation: Raised, On Grade, and Below-Grade

Basements and Crawl Spaces
Slab Foundations
Desired Outcome: 
Effective air barrier Air barrier The separation between the interior and exterior environments of a building that slows air flow to the point that no smoke movement is visible at 50 pascals of pressure difference across the boundary between the conditioned space and the ground
For supporting material, see Referenced Standards.

Conduct pre-inspection in accordance with SWS 2.0100.4 Work Area Inspection and Stabilization

Where applicable (generally above-grade concrete slabs between conditioned and unconditioned spaces), gaps, cracks, and holes in fire separations located within the work area will be visually identified and incorporated into air sealing work scope, including those that span two conditioned or unconditioned spaces

Where drawings are available that identify specific fire-resistance ratings (i.e., 1 hour, 2 hour), materials and methods will be employed to preserve or restore such rating

Where drawings are unavailable or do not identify specific fire-resistance ratings, the fire-resistance rating of the assembly may be inferred from the current construction (i.e., single 5/8 sheetrock, concrete masonry unit), and materials and methods employed will be consistent with restoring or preserving such inferred fire-resistance rating

Where applicable, for assembly type and geographic location, test for radon per ANSI ANSI American National Standards Institute, www.ansi.org - AARST AARST American Association of Radon Scientists and Technologists, www.aarst.org Standard: Protocol for Conducting Radon and Radon Decay Product Measurements in Multifamily Buildings

Repairs necessary to stabilize work areas and protect or preserve integrity of energy improvement will be completed before subject work begins

Identify and correct conditions which contribute to excessive radon levels

Provide a stable slab to ensure durability of the work

Identification of penetrations

Penetrations will be identified using visual inspections, smoke, and/or pressure tests [ ASTM ASTM ASTM International, www.astm.org E1186-03 (2009)]

Locate air leakage pathways to repair


Health and safety concerns for occupants and workers, in relation to repairs and materials, will be addressed in accordance with OSHA OSHA U.S. Occupational Safety and Health Administration, www.osha.gov standards ( OSHA OSHA U.S. Occupational Safety and Health Administration, www.osha.gov 1926, 1910)

The area will be prepared and isolated in accordance with health and safety standards for the application and materials (e.g., extreme temperatures, lead, asbestos, carbon monoxide, moisture)

Work lighting, work platform, and adequate ventilation will be provided

Access not provided will be created to ensure that repairs can be made (may include localized demolition)

Provide a safe work environment

Provide safe indoor environmental quality in the work environment

Provide effective repair access

Sealant and materials selection

Sealants and materials will be compatible with their intended surfaces and applied in accordance with manufacturer specifications

Selection will be durable, pest resistant, and have a weather-appropriate seal

Indoor sealants will be low volatile organic compound ( VOC VOC Volatile organic compound ) products that meet independent testing and verification protocols, such as Green Seal GS-36, "GREENGUARD Children and Schools," or comparable certifications

Fire-resistance-rated assemblies will be provided with sealants permitted by the authority having jurisdiction and adopted building code

Where penetrations are due to failed or missing expansion joints, sealing materials will be suitable for this application

Prevent intrusion of moisture and pests into the sealed assembly

Prevent exposing workers or occupants to excessive VOC VOC Volatile organic compound levels

Ensure sealant meets or exceeds the performance characteristics of the assembly and is compliant with local fire code requirements

Demolition repair

Access holes will be repaired

Restore surfaces to original condition or better


Repairs will be verified by visual inspections, smoke, and/or pressure tests consistent with the pre-inspection

Ensure quality and effectiveness of air sealing