What do I do if an RTU curb gasket is torn or missing at a corner?

A curb gasket failure can become a roof leak into the supply/return opening. Do not hide it with outside caulk only; document it and get the unit reseated/re-gasketed by the approved method.

['The gasket between RTU and curb is a primary weather/air seal. If it is stretched thin, skipped, torn, dirty, or compressed wrong at a corner, water and air can get into the building or plenum.', 'The correct repair may require lifting/jacking the unit enough to clean the curb and replace the gasket, not just smearing sealant around the outside. Coordinate with foreman, crane/rigging, roofer, safety, and manufacturer/project detail before moving equipment.']

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

• A bad curb gasket can leak rain into the building, create air leakage, damage insulation/ceilings, and be expensive to repair after startup.

Steps

• Inspect all curb corners before the crane unhooks when possible.
• Check for torn, stretched, dirty, missing, or folded gasket.
• Look for curb damage, plenum opening exposure, roof membrane issues, and unit alignment.
• Document the condition with photos before weather hits or the unit is fully tied in.
• Coordinate safe lifting/jacking and roofer/equipment requirements before repair.

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