Static field route #19626

What do I do when a multi-section louver leaks at the vertical mullion splice?

Sealing, Leakage, Mastic & Pressure Testing⚠️ CHECK FIRSTField answer expansion

📖 Verified core answer

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

Open in Field Rescue Open category

Field verification checklist

Track where water enters and where it exits.
Check for missing vertical gutter, splice channel, or butyl sealant.
Make sure the sill pan/weep path is open.
Confirm whether the joint needs movement clearance.
Water-test only after the internal drainage path is corrected.

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?

Text to foreman

Route options

A Correct it only if the fix is within your assignment and approved method.

B Hold and document if it affects water intrusion, weatherproofing, rated assemblies, structural anchorage, controls, TAB, or another trade.

C Bring the foreman/detailer the location, what you checked, and what decision you need before sealing, testing, cover, or startup.

Do not do this

Do not smear exterior silicone over a multi-section louver joint and call the water path fixed.

Why this matters

The water may still run behind the face seal and drip onto equipment or interior finishes.

Final verification

Use this as field training guidance. Final direction still comes from the foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, pressure/material schedule, and AHJ/code requirements.

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