Apprentice answer

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

3rd YearMaterial Handling, Lifts & RiggingStop / Verify

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.

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Plain-English answer

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.

Field checklist

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.

Ask Foreman

The RTU curb gasket at [corner/location] is torn/missing/folded. I checked the curb and unit alignment. Do you want us to lift/reseat and replace gasket per the approved detail before we tie this in?

Verify before acting

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.

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