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Apprentice answer

Why does silicone on the outside not fix a leaking louver splice

3rd YearRoof Curbs, Louvers & Exterior AirCheck first

A louver splice needs a drainage path, not just face caulk. Install or correct the internal gutter/splice channel per the louver detail.

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Plain-English answer

Water can migrate through the joint between louver sections. If the joint is supposed to have an internal gutter or splice channel, smearing silicone on the outside can trap water or fail after movement.

Open the inside joint if accessible, check for missing gutter/splice parts, and rebuild the joint so water is captured and routed to the sill/weeps. Use the approved sealant inside the joint, not as a cosmetic band-aid on the face.

Ask Foreman

The multi-section louver at [location] leaks down the vertical splice. I checked the face and sill path. Do you want the internal gutter/splice channel opened and corrected?

Verify before acting

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

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