Glass in picture framing refers to a clear, rigid sheet of glazing material placed over artwork to protect it from dust, moisture, pollutants, and physical contact. Certain types of glass are also designed to reduce glare and block harmful ultraviolet (UV) rays, helping preserve artwork over time.

Functions of Glass in Framing

Physical protection: shields the artwork surface from dust, dirt, and fingerprints.
Environmental barrier: reduces exposure to moisture and airborne pollutants.
UV filtering: some glass types, such as conservation glass, provide UV protection to slow fading and deterioration.
Presentation enhancement: anti-reflective and museum glass improve visibility by reducing glare and reflections.

Types of Framing Glass

Conservation Clear Glass: provides 99% UV protection while maintaining clarity. Learn more.
Anti-Reflective Glass: optical coatings minimize glare and reflections, offering nearly invisible viewing. Learn more.
Museum Glass: premium glazing that combines UV protection and anti-reflective qualities.
Convex Glass: curved glass used to create depth or fit specific styles of frames. Learn more.
Regular Clear Glass: the most economical option, but provides no UV protection and can produce glare.

Considerations When Using Glass

Regular glass is heavier and more fragile than acrylic glazing alternatives.
Glass should not touch delicate artwork directly-use mats or spacers to prevent sticking or abrasion.
Choose UV-filtering glass for valuable or light-sensitive artworks, especially watercolors, photographs, and textiles.
For oversized works, acrylic may be a safer, lighter alternative to glass.

Best Practices

Use conservation-grade glass for preservation framing of valuable or irreplaceable artwork.
Select anti-reflective or museum glass for display pieces where glare reduction and clarity are priorities.
Always incorporate a spacer or mat to prevent direct contact between glass and artwork.
Ensure the glass is cut accurately to the frame window size with a glass cutter or scoring tool.

FAQs

Is glass better than acrylic for framing?: Glass is more scratch-resistant and often clearer, but it is heavier and more prone to breakage. Acrylic is lighter and shatter-resistant, making it preferable for large or transportable works.
Does all framing glass block UV light?: No. Only specialized types, such as Conservation Clear Glass or Museum Glass, offer UV filtering. Standard clear glass provides no protection against UV rays.
When should I use convex glass?: Convex glass is primarily used in vintage or decorative frames where a domed presentation is desired, often for portraits or memorabilia.

Glass