How Do I Fix a Magnetic Fly Screen That Won't Stay in Place?

Magnetic fly screens shift, gap, and peel away from doorframes for a few common reasons. Surface contamination stops the magnets gripping, the adhesive backing loses its bond over time, or the screen wasn’t seated squarely when first fitted.

It’s a fixable problem. Most of the time you won’t need a replacement screen, just a bit of cleaning and a strip of new magnetic tape.

What You’ll Need

Tools

• Scissors or a craft knife
• Tape measure
• Pencil or chalk marker
• Cloth or sponge

Materials / Replacement Parts

• Warm water with a small amount of washing-up liquid
• Isopropyl alcohol (optional, for stubborn grease)
• Adhesive-backed magnetic tape (same width as your existing strip)
• Drawing pins or temporary clips (to hold the screen while adhesive sets)

How to Fix It: Step-by-Step

Step 1: Work Out What’s Actually Wrong

Before you pull anything apart, look at where the screen is failing. A screen that gaps at the centre has different causes from one that’s falling off the frame entirely.

• Run your fingers along the magnetic seam. Do both sides click together cleanly, or does it feel weak and patchy?
• Check whether the outer frame is still stuck to the doorframe. Press on each corner and each side.
• Look for visible damage: torn fabric, kinked magnetic strips, or areas where the adhesive has clearly let go.
• If the screen gaps only at the centre, the panels may just be misaligned. Peel them apart, rehang, and re-press them from top to bottom.

Step 2: Clean the Magnetic Contact Surfaces

Grease, dust, and pet hair are the main culprits when magnets stop holding. They don’t need to be visibly dirty to cause problems.

• Mix a small amount of washing-up liquid with warm water.
• Wipe down both sides of the magnetic strip where they meet in the centre.
• Clean the adhesive side of any frame-mounted strips if they’re accessible.
• For oily residue (sunscreen, cooking grease near a kitchen door), use a cloth with a little isopropyl alcohol.
• Let everything dry completely before testing. Magnets on damp surfaces won’t grip properly.

Step 3: Replace Weak or Detached Magnetic Strips

If cleaning doesn’t solve it, the magnetic tape itself is the problem. Over time the adhesive weakens, especially in sun-facing doorways or anywhere that sees temperature swings.

• Peel away any strips that have lifted or separated. Work slowly to avoid pulling the screen fabric.
• Cut a length of fresh adhesive-backed magnetic tape to match the original. Get the polarity right before you stick it down: hold the new tape next to the opposite strip on the screen and check they attract rather than repel.
• Press the tape down firmly and hold for 30 seconds. Run your thumb along the full length.
• Use drawing pins or temporary clips to hold the screen in its correct position while the adhesive cures. Give it an hour before testing under normal conditions.

Step 4: Recheck the Frame Fit and Test

A screen that keeps failing often has an underlying fit problem. Check this before calling it done.

• Hold the screen flat across the doorway and look for any bow in the frame. If the frame isn’t sitting flush against the door surround, the magnetic strips can’t make full contact.
• Press the frame corners firmly against the wall surface. If any are loose, add a small strip of double-sided tape behind them.
• Walk through the screen ten or fifteen times at normal speed. Watch whether it closes fully each time or whether a section consistently stays open.
• If one side reliably lags, shift that side’s frame strip inward by a few millimetres so the magnets have less distance to bridge.