Portuguese Prepper
Window Security Film: Invisible protection for your home
Once you have reinforced your doors, the next obvious weak point is the glass. A burglar can simply throw a brick through a window and step inside.
Security Window Film is a thick, clear polyester layer that you apply to the interior of your windows. It acts like the safety glass in your car windshield. When struck, the glass shatters, but the film holds the shards together in a solid sheet. This prevents a “Smash and Grab” and forces the intruder to spend valuable minutes hacking at the window to create a hole.
Thickness Matters: Measured in “mils” (1 mil = 1/1000 inch).
UV Protection: Blocks 99% of UV rays (protects furniture).
Anchoring: For maximum strength, the film must be anchored to the frame.
Understanding “Mils” (Thickness)
4 Mil: Basic protection. Holds glass together if a soccer ball hits it. Good for safety, weak for security.
8 Mil: The standard for residential security. Can withstand a brick or a baseball bat strike without failing immediately.
12 Mil+: Government/Commercial grade. Extremely thick and difficult to install yourself. Used for bomb blast mitigation.
The “Anchoring” Secret
If you just stick the film to the glass, a burglar can hit the window hard enough to pop the entire pane of glass out of the frame (the glass breaks, but stays attached to the film, and the whole sheet falls inward).
To prevent this, you use a Structural Silicone Adhesive (like Dow Corning 995) to glue the edge of the film to the window frame. This bonds the glass, film, and frame into one solid unit.
Which film should you apply?
Storm Protection Benefit
This is not just for burglars. If you live in a hurricane or tornado zone, security film prevents glass from flying across the room if a tree branch hits your window. It is a dual-purpose survival upgrade.
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