How to Install a Screw-On Bulb Seal Weatherseal on a Hollow Metal Door Frame

This step-by-step guide explains how to properly install a screw-on bulb seal perimeter weatherseal on a commercial hollow metal door frame. Bulb seals are commonly used to improve air sealing, sound control, and energy efficiency oncommercial steel door openings.

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Video: Screw-On Bulb Seal Installation

Tools & Materials Needed

• Screw-on bulb seal perimeter gasket (head + two jamb pieces)
• Supplied mounting screws (#6 or #8 pan-head)
• Tape measure and pencil
• Drill/driver with pilot bit
• Utility knife or shears
• Safety glasses

Download the official installation manual here:
Screw-On Perimeter Seal Installation Instructions (PDF)

Step 1: Prepare the Door Frame

Remove any existing weatherseal, adhesive, or debris from the frame stop.Clean the mounting surface so the seal sits flat and straight.Verify the door is properly aligned and latching correctly before installing the seal.

Step 2: Measure and Cut the Seal

Measure the inside width of the frame head and cut the top seal to length.Measure both jamb heights and cut the vertical pieces.For best results, miter the corners at 45° so the bulb compresses evenly at the corners.

Step 3: Dry Fit and Mark Fastener Locations

Hold the seal against the frame stop and confirm the bulb faces the door.Mark fastener locations approximately 8"–12" on center.Pre-drilling pilot holes is strongly recommended for hollow metal frames.

Step 4: Install the Head Piece

Fasten the head section first, starting at the center and working outward.Do not overtighten — the bulb should compress slightly but not flatten.

Step 5: Install the Jamb Pieces

Install each jamb seal starting at the top corner and working downward.Maintain consistent bulb alignment so compression is uniform when the door closes.Trim excess at the bottom so the seal stops just above the threshold.

Testing and Adjustment

• Close the door and confirm smooth operation
• Verify even bulb compression on all sides
• Adjust door closer latch speed if needed
• Ensure the door still latches without excessive force

Related Hollow Metal Door Resources

• Hollow Metal Door Installation Guides
• How to Properly Hang a Hollow Metal Door
• Install a Hollow Metal Drywall Frame
• Install a Steel Door in an Existing Block Wall

Need Help Selecting the Correct Weatherseal?

Send us a photo of your door frame or call our technical team.We’ll help you match the correct bulb size and frame profile.

Call:866-232-5673
Text:210-275-8966

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DISCLAIMER: Information provided is for general guidance only.Always follow the manufacturer’s installation instructions and applicable building codes.