CHOOSING THE RIGHT SKYLIGHT GLAZING MATERIAL:
Glass vs. Polycarbonate vs. Acrylic

March 29, 2021

All forms of daylighting typically work toward the same goal – allowing natural light to illuminate the interior of a building. Skylights can brighten a room, add to the warmth of a home, and serve as a decorative flourish to complement the interior style of a house. They can also serve functional and aesthetic purposes for commercial facilities. If you are thinking of purchasing a skylight, you want to make sure that you select the right type for your specific needs and preferences.

A building’s design, orientation, and end use often dictate which type of system is most effective for a space, therefore evaluating which glazing material will work best for the application is important. Because skylights are available in many different styles and can be made using a variety of materials, the question of skylight glazing can be a tricky one.

There are big differences between glass, polycarbonate, and acrylic skylights. And knowing what makes each unique can help better assist you in choosing the type of skylight that is right for your project.

First, it is important to note that glass and polycarbonate panels are only available in flat profiles, and therefore require a suggested minimum of a 2:12 pitch to allow moisture to drain properly, in order to be within DĀLYTE’s warranty guidelines. Installing flat glazing on a flat roof will pool water, develop water rings where dust will collect, and cause the glazing to constantly look dirty.

When working on a flat roof, DĀLYTE recommends two skylight options: 1) Formed Acrylic Dome Skylights or 2) a Structural Skylight to introduce a pitched geometry.

Let’s take a closer look at some of the attributes and application considerations for DĀLYTE’s three glazing options below.

GLASSchoosing-the-right-skylight-glazing

Glass is perhaps the most immediately recognizable and common glazing material available for daylighting systems – and for good reason. Glass is durable, is available with a wide variety of films for light and UV control, comes in numerous configurations and styles, and offers eye-catching views to the outdoors. Additionally, it is the most thermally efficient when compared to other glazing types.

On the flipside, glass is heavy compared to most other glazing materials and demands significant structural support which may increase material and installation costs. Depending on the unit type, whether architectural structural or curb mount, lead times may vary.

That said, if dramatic impact, views, and ventilation control are key requirements for a space, glass is an excellent choice.

Glass Features:

  • Longest life expectancy
  • Best insulation values
  • Greatest number of custom options available
    • Allows for the use of different low-e coatings, films, thicknesses and PVB interlayers to achieve specific goals (i.e., walkable / bullet resistant).
  • All overhead glass is “safety glass” comprised of a ¼” tempered outer layer, ½” air space, and a 5/16” inner layer of heat-strengthened laminated glass. Glass skylights using this construction conform to OSHA fall requirements.
  • Available in multiple color options
  • The ideal glazing material for residential skylights, sunspaces, and greenhouses

POLYCARBONATE MULTI-WALLchoosing-the-right-skylight-glazing

If glass is too heavy and costly, consider polycarbonate multi-wall panels. Like the name suggests, this type of glazing is made up of multiple-walled extruded polycarbonate panels that can be used in skylight, wall, and canopy configurations.

One of the main benefits of polycarbonate multi-wall is its ability to diffuse natural light (this varies depending on the material chosen). It is also very lightweight, durable, and impact resistant, and offers a variety of color and size options to control light transmission and thermal performance. Polycarbonate is resistant to extreme temperature either hot or cold, sunlight, snow, rain, and impact. This enables the panels to last for many years without fading or discoloring while also remaining damage-free from any various impacts over the years.

Although durable and unbreakable, polycarbonate is not as scratch resistant when compared to other glazing types, and therefore, denting or scratching on the surface is possible if extra caution and care is not taken.

For a simple clerestory, skylight, or canopy, polycarbonate multi-wall is an economical choice. Its impact-resistant properties also make it a good choice for athletic facilities and other impact-prone areas, and its light weight makes it useful for retrofit applications.

Polycarbonate Multi-wall Features:

  • 10-year warranty against hail and yellowing
  • Best insulation values versus acrylic
  • Customizable material thickness to meet different project requirements
    • Different thickness (16mm, 25mm, 40mm) with different flute fill patterns (number of walls) can greatly increase the insulation values with minimal impact on light transmission.
  • Can be used to replace existing fiberglass products that have yellowed or suffered fiber bloom
  • Very sleek modern appearance
  • Excellent for use in exterior canopies and budget-conscious greenhouses

ACRYLICchoosing-the-right-skylight-glazing

Acrylic tends to be the more economical and practical choice when it comes to skylight glazing material. It is lighter than glass and suitable for installation on roofs with low slopes or flat roofs. Due to its natural strength, acrylic is the preferred material for skylight domes. Acrylic is also naturally UV stable and will withstand years of abuse from the sun. Acrylic also allows for more design flexibility, is easier to handle and is available in larger sizes.

Acrylic Features:

  • The most common used glazing for commercial and industrial spaces
  • Long lifespan (25-30 years under normal conditions) due to effective handling of UV light
    • Standard Acrylic is NOT impact rated
    • Available Impact Modified Acrylic adds rubber to the composition, which greatly increases impact rating
  • Available UV-blocking Acrylic is available. Skylights with this option help prevent the “bleaching” effect on interior surfaces over time.
  • Less expensive than glass and polycarbonate

WHAT’S THE BEST SOLUTION?choosing-the-right-skylight-glazing

First consider the application-does the space demand soft, diffuse light, or would it benefit from a dramatic view or localized ventilation control? Also, carefully review the benefits and drawbacks of each material, from lifespan to warranties and durability.

At DĀLYTE, our knowledgeable team of daylighting experts can assist you in selecting the best material options for your next project. We will work with you to create a custom configuration that will fit both your needs and budget. Contact us today at sales@dalyteusa.com or at (800) 748.2036.

Discover your options. Learn about the latest skylight designs and materials for home, office, or industrial properties by visiting the DĀLYTE website.