Where should a fire damper sleeve sit in a rated wall opening?

Do not force retaining angles onto a sleeve that is too far in or out. Reposition the sleeve/damper per the manufacturer wall-opening detail so blades, sleeve, angles, and access all work.

['If the sleeve projects too far or sits too deep, the retaining angles may not seat, the damper may not sit correctly in the rated wall, and access/actuator clearances may be wrong.', 'The correction is to check the damper installation instructions, wall thickness, sleeve extension limits, blade location, and retaining angle requirements. Slide/reset the sleeve before firestop, drywall closure, or inspection if it is not positioned per the listed detail.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Check

• Bad sleeve position can fail inspection, block access, prevent proper retaining angle installation, or affect damper operation.

Steps

• Check damper tag/model and manufacturer installation sheet.
• Measure wall thickness, sleeve projection both sides, blade location, and retaining angle fit.
• Verify actuator/linkage/access side and whether access door still works.
• Check wall/sleeve gap and firestop sequence before cover.
• Ask before trimming sleeve or moving a rated assembly.

More in Fire/Smoke Dampers & Rated Assemblies