precisionfilmsystems.com/resources/customer-glossary/Customer Window Film Glossary
These definitions are written for customers. Product sheets may use more exact test conditions, combined glass-and-film values, or manufacturer-specific language. Ask the installer which number and test method apply to the proposed film and glass.
Light, solar energy, and appearance
Visible light transmission (VLT)
The percentage of visible light that passes through the glass and film system. A lower number generally means less visible light passes through, but VLT alone does not describe heat performance or nighttime privacy.
Why you may see this: It helps describe how light or dark the finished glass may appear. Read the technical explanation.Reflectivity
How much visible light is reflected by the glass and film system. Interior and exterior reflectivity can differ, and the appearance changes with lighting on each side.
Why you may see this: It helps set expectations for daytime and nighttime appearance. See reflectance in practical terms.Glare
Brightness or reflected light that makes a screen, view, or work area uncomfortable. Glare reduction is related to visible light, but it is not the same as solar heat reduction.
Why you may see this: It may be a primary goal in offices, living spaces, classrooms, or display areas. Read about glare tradeoffs.Ultraviolet radiation (UV)
A non-visible part of sunlight that contributes to fading and material damage. Film can reduce UV exposure, but visible light, heat, material chemistry, and time also affect fading.
Why you may see this: UV reduction is a common product value, but it should not be read as complete fading prevention. Read the UV explanation.Infrared energy (IR)
A non-visible part of solar energy often discussed in relation to heat. An IR value may refer to a selected wavelength range and should not be treated as the full solar-performance result.
Why you may see this: Some product comparisons promote IR rejection prominently. Compare IR and heat rejection.Solar heat gain
Solar energy that enters through the glass and contributes to heat inside. Glass, film, orientation, exposure, shading, and the building all influence the result.
Why you may see this: It connects the glass system to cooling and comfort discussions.Total solar energy rejected (TSER)
A measure of how much total solar energy the glass and film system rejects. It includes more than visible light or one selected infrared range.
Why you may see this: It is used to compare overall solar performance under stated test conditions. Read the TSER explanation.Glass construction
Low-emissivity (Low-E) glass
Glass with a coating designed to control radiant heat transfer. The coating surface, glass construction, selected film, and current manufacturer guidance are important in a compatibility review.
Why you may see this: Low-E should be identified before film is recommended. Read the Low-E explanation.Dual-pane glass
An insulated glass unit made with two panes separated by a sealed space. Coatings, gas fill, spacers, glass type, existing condition, and exposure may all be relevant to film selection.
Why you may see this: A proposal or compatibility review may identify the insulated glass construction.Tempered glass
Heat-treated safety glass designed to break into smaller pieces. Tempering is one part of the glass description; it does not replace the rest of the film-to-glass review.
Why you may see this: Glass markings or building records may identify tempered panes.Laminated glass
Glass made with an interlayer that helps hold fragments together after breakage. The laminated construction, thickness, coatings, exposure, and selected film matter to the product review.
Why you may see this: Laminated glass is common in specified safety, security, acoustic, or overhead applications.Film types and applications
Safety film
Film designed to help hold broken glass together for specified safety applications. Performance depends on the product, glass, framing, attachment details, installation, and tested system.
Why you may see this: The proposal may address accidental impact, fragment retention, or another stated safety goal. Compare safety and solar film.Security film
A film or film-and-attachment system specified for particular intrusion or impact goals. The term does not mean that every product provides the same performance, and window film alone should not be described as bulletproof.
Why you may see this: Security work should identify the tested system and the goal it is intended to address.Decorative film
Film used to change the pattern, color, opacity, branding, or appearance of glass. It may be clear, frosted, translucent, patterned, colored, or opaque.
Why you may see this: Decorative film can add visual separation or design without replacing the glass. Compare decorative coverage terms.Privacy film
Film selected to change visibility through glass. The result depends on opacity, reflectivity, pattern, viewing distance, and lighting on each side.
Why you may see this: Daytime reflective privacy and nighttime privacy are not the same. Read about the lighting tradeoff.Ceramic film
A product description commonly used for films that use ceramic materials in their construction. The label does not provide the full performance result; use the manufacturer’s product data for the exact film.
Why you may see this: It may describe a product family or construction method rather than one fixed appearance or performance level.Metallized film
Film that uses metallic layers or particles to influence solar performance and appearance. Products vary in visible reflectivity, color, construction, and performance.
Why you may see this: Film-construction language can help explain appearance and product differences. Compare common film labels.Selection, installation, and warranty
Warranty
The manufacturer or seller terms that describe covered products, conditions, limits, required records, and claim procedures. Coverage is tied to the written warranty, not a general product description.
Why you may see this: Keep the completed warranty, invoice, product name, installer information, and installation date.Film-to-glass compatibility
Whether a specific film is suitable for a specific glass configuration under current manufacturer guidance and the stated job conditions. It is not a blanket approval for a film category or glass label.
Why you may see this: Exact film, glass, coatings, exposure, shading, installation side, and condition may all need review. See what installers check.Interior installation
Film applied to an interior-facing glass surface. Most product and compatibility information identifies which surface is intended for installation.
Why you may see this: Interior and exterior versions of a product may have different construction, warranty, and exposure limits.Exterior installation
Film designed and approved for an exterior-facing glass surface. Exterior exposure changes durability, installation, care, edge treatment, and warranty considerations.
Why you may see this: Access or glass construction may lead to an exterior product being considered.Drying or curing period
The product- and condition-dependent period after installation while moisture leaves and the adhesive system develops. Appearance may change during that period.
Why you may see this: The installer should provide the timing and care guidance for the exact film and job conditions.