Mil thickness is the easiest number on a quote to compare and one of the least complete. Whether security film is worth it depends on what you need the opening to do — and on the glass, attachment and frame around the film.
Security film holds broken glass together. That can reduce flying and falling fragments and make a broken pane harder to clear quickly. What it cannot do on its own is turn ordinary glass into a rated barrier. Results depend on the glass type and size, the film, whether the film is attached to the frame, and the condition and anchorage of the frame itself.
Fragment retention and safety glazing: keeping broken glass together after accidental impact or storms.
Forced-entry resistance: slowing a person trying to break through, which depends heavily on attachment to the frame. No film system guarantees a fixed delay time.
Ballistic resistance: requires a tested, qualifying system. Ordinary security film is not bulletproof.
These are the product families documented on our product pages; always use the current manufacturer specification for the exact project.
3M Scotchshield Ultra S800 — an 8 mil micro-layered polyester security film.
3M Safety S140 — a 14 mil film; 3M calls for the Impact Protection Attachment (IPA) for all break-and-entry applications.
3M Scotchshield S2400 — a 24 mil TPU-based film; the manufacturer specification does not allow it to be combined with a PET security film on the same pane.
3M Impact Protection Attachment — a structural attachment that bonds the filmed glass to the frame.
A thick film that ends at the glass edge can still let the whole filmed pane be pushed out of the frame as one sheet. Attachment systems connect the film to the frame so the glass, film and frame resist together. That is why a properly attached thinner system can be the more appropriate answer for one opening while a thicker film without attachment may not meet the objective at another.
When the requirement is ballistic resistance, the conversation moves to tested systems such as C-Bond’s ballistic-resistant glass systems, described by the specific qualifying test report and configuration. That is a different scope from security film and should be specified as a system, not as a thicker film.
Exact film name and manufacturer document revision, not just a mil number.
Whether attachment is included, which system, and on which openings.
Glass type identified for each opening (tempered, annealed, laminated, insulated).
Frame condition notes and any openings excluded.
The applicable manufacturer warranty document.
Clear wording that avoids universal delay times or “bulletproof” claims.
Cost depends on film choice, glass size and count, whether attachment is used, access and the condition of the frames. We do not publish a universal price because attachment and access often change a project more than the film itself. Photos of the openings and approximate sizes are enough to start an estimate.
Is thicker security film always better? No. Thickness is one input. Glass type, attachment and frame condition often decide whether the opening meets its objective.
Is window security film worth it? For fragment retention and added resistance on suitable glass, often yes. Define the objective first, then choose film and attachment to match.
Is security film bulletproof? No. Ballistic resistance requires a tested qualifying system, which is a separate scope.
Does security film guarantee a delay time? No. Performance depends on the whole opening and the attack; avoid any quote that promises a fixed delay.
Safety: Fragment retention and the applicable safety-glazing assembly.
Forced entry: Glass, film, attachment and frame reviewed together; no guaranteed delay.
Ballistic: A separate qualifying tested system—not ordinary security film.
Request a free estimate or call (302) 947-4624. Shore Tint & More (Delaware Window Film) — 3M Authorized Dealer, IWFA accredited, serving Delaware and the Maryland Eastern Shore since 1989.