3.1502.1 Garages—Isolating from Living Spaces

Attached Garages
Isolating From Living Space
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 garage and all other spaces of the building prevents carbon monoxide ( CO CO Carbon monoxide ) and exhaust fumes from entering the building
For supporting material, see Referenced Standards.
Pre-inspection, including combustion safety

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

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

All below-grade and enclosed garages will be equipped with operational exhaust systems that depressurize the garage space with reference to the building

Pressure differential of all garages (both enclosed and open) to building will be measured

Carbon monoxide ( CO CO Carbon monoxide ) levels will be measured in the garage and building under typical operating conditions before work begins

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

Repair or address moisture, pest, and structure-related issues

Repair ventilation-related issues

Provide a safe and stable work environment

Identification of penetrations

Penetrations will be identified using one or more of the following:

  • Visual inspections
  • Infrared thermography
  • Air flow detection smoke or visible mist
  • Induced pressure tests [ ASTM ASTM ASTM International, www.astm.org E1186-03 (2009)]

The following will be included in the investigation:

  • Penetrations through walls and ceilings that separate garage from occupied space
  • Doorways between garage and occupied space
  • Cracks at sill and rim joist between garage and occupied space, basement, or crawl space
  • Ductwork and heating, ventilation, and air conditioning equipment located in the garage that serves occupied space

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)

CO CO Carbon monoxide levels will be monitored in work areas during repair work consistent with relevant OSHA OSHA U.S. Occupational Safety and Health Administration, www.osha.gov requirements

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, CO CO Carbon monoxide )

Work lighting, work platform and adequate ventilation will be provided

Provide a safe work environment

Provide safe indoor environmental quality in the work environment

Protect workers from CO CO Carbon monoxide exposure

Provide effective repair access

Installation, 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

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


Pressure differential of garage to building will be measured

CO CO Carbon monoxide levels in the building will be measured

Ensure quality and effectiveness of air sealing