The Complete Guide to Polycarbonate Sheets

Laird Plastics Resource Article

Introduction to Polycarbonate Sheets

Polycarbonate sheets are sheets made from polycarbonate plastic. Polycarbonate is an incredibly versatile thermoplastic material that is known for its high impact strength, light weight, optical clarity, and heat resistance. 

Compared to other plastic materials like acrylic or polypropylene, polycarbonate stands out for its durability and flexibility. It has very high impact strength, making it virtually unbreakable under normal conditions. Polycarbonate sheets are up to 250 times stronger than glass sheets of the same thickness. At the same time, polycarbonate is half the weight of glass and much easier to work with.

Polycarbonate also has excellent optical properties. It has high light transmission and a glass-like transparency. Polycarbonate sheets maintain their optical clarity even after years of exposure to UV light, which makes them perfect for outdoor applications.

The combination of extreme strength, lightweight, and optical clarity makes polycarbonate an ideal material for applications ranging from greenhouses to skylights, safety glazing, machine guards, and more. It's stronger than acrylic yet lighter than glass. Polycarbonate offers the best of both worlds - glass-like optical qualities and plastic-like fabrication abilities.

Types of Polycarbonate Sheets 

Polycarbonate sheets are available from a variety of brands and manufacturers. Some of the major suppliers include:

Polycarbonate sheets typically range in price from $1 to $5 per square foot depending on the thickness. Thinner sheets around .060” tend to cost $1-2 per square foot while thicker 1/4” to 1/2" sheets can cost $3-5 per square foot. Quantity discounts are often available on large orders.

Key Properties and Strengths of Polycarbonate Sheets

Polycarbonate sheets stand out from other plastic materials due to their exceptional strength properties and durability. Here are some of the notable qualities that make polycarbonate an excellent choice for many applications:

Impact and Shatter Resistance

Polycarbonate has very high impact resistance. It is virtually unbreakable and up to 250 times stronger than glass. Polycarbonate sheets can withstand the strike of a small object at up to 120 miles per hour! Even at sub-zero temperatures, polycarbonate retains its flexibility and resilience. This makes it ideal for applications like machine guards, riot shields, bullet-proof windows, and other uses requiring ultimate strength.

UV Blocking Ability 

Polycarbonate naturally blocks UV light, making it highly resistant to sun damage. UV-resistant grades block up to 99% of UV rays. Even after prolonged sun exposure, polycarbonate retains its strength and optical clarity much better than other plastics. This makes it perfect for exterior uses like greenhouses, skylights, and outdoor fixtures.

Optical Clarity and Light Transmission

Polycarbonate has excellent clarity close to that of glass. Standard grades transmit up to 89% of visible light. This high light transmission makes polycarbonate ideal for applications like windows, lenses, and transparent parts that require clarity. The material stays transparent even after years in the sun. Polycarbonate also provides privacy while allowing light passage.



Polycarbonate vs. Other Materials

Polycarbonate sheets have some key advantages and differences when compared to other common materials like glass, acrylic, and PVC.

Polycarbonate vs. Glass

Polycarbonate is lighter and more impact resistant than glass. It will not shatter like glass, making it a safer choice for applications where breakage is a concern. Polycarbonate also blocks UV rays better than most glass. However, glass is more scratch resistant and has better optical clarity than polycarbonate.

Polycarbonate vs. Acrylic

Polycarbonate is stronger and more flexible than acrylic. It also has higher impact resistance, especially at low temperatures where acrylic can become brittle. Polycarbonate withstands weathering and UV exposure better than acrylic. However, acrylic is more scratch resistant and less likely to turn yellow over time.

Polycarbonate vs. PVC

Polycarbonate is lighter, clearer, and stronger than PVC plastic sheets. It is also more impact resistant at low temperatures. PVC sheets are cheaper, but they scratch easier and lack the transparency of polycarbonate. PVC also tends to turn yellow faster when exposed to sunlight. Polycarbonate offers better durability for long-term use.

So in summary, polycarbonate's strength, UV resistance, and clarity make it superior to glass, acrylic, and PVC for applications like greenhouses, skylights, and bullet-resistant barriers. It provides an excellent balance of properties at a reasonable cost.

Applications and Uses

Polycarbonate sheets are valued for their durability, clarity, and lightweight strength, making them ideal for a variety of applications. Here are some of the most common uses for polycarbonate sheets:

Greenhouses

Polycarbonate is the glazing material of choice for greenhouse construction. The sheets provide high light transmission while blocking harmful UV rays, supporting plant growth. Polycarbonate's high impact strength also resists hail damage and withstands extreme weather, which is essential for outdoor structures. Polycarbonate panels are easy to install to create full greenhouses or simple cold frames. The sheets are an affordable and long-lasting glazing option compared to glass.

Skylights and Windows 

Polycarbonate is an excellent material for skylights and windows. The sheets let in natural daylight while insulating interiors. Polycarbonate's impact resistance makes it safer than glass near walking paths or in high-traffic areas. The sheets can be molded into curved shapes to create barrel-vault skylights or unique architectural features. Compared to glass skylights, polycarbonate offers better energy efficiency.

Signage

Polycarbonate is widely used for indoor and outdoor business signage. The lightweight sheets are easy to cut, drill, and form into dimensional letters or sign boxes. Polycarbonate resists fading and yellowing from sun exposure better than other plastics. The durable material holds up well in public spaces despite weather, sun, and potential vandalism. Backlit polycarbonate sign boxes create bright, eye-catching displays.

Installation and Fabrication

Polycarbonate sheets can be fabricated and installed using common tools and methods. Here are some tips:

Cutting Polycarbonate Sheets

  • - Use a circular saw with a fine-toothed blade to get clean, smooth cuts. Go slowly to avoid cracking.
  • - A table saw also works well for straight cuts. Clamp the sheet to keep it steady. 
  • - For curved cuts, a jigsaw is ideal. Use a blade with 10 teeth per inch.
  • - A laser cutter can also be used for precise, complex cuts.
  • - Allow the sheet to cool after laser cutting before handling to prevent cracking.

Drilling and Machining 

  • - Drill holes using sharp twist or spur bits. Back up the sheet with scrap wood.
  • - Low drill speeds are best to avoid overheating. Lubricate the bit with oil or soapy water.
  • - For tapping threads, use a tap appropriate for plastics.
  • - A CNC router can machine complex holes and cutouts.

Joining and Bonding

  • - Polycarbonate edges can be joined with adhesives like methylene chloride solvents.
  • - For structural strength, use aluminum or composite H-channels between sheets. 
  • - Silicone sealant creates weatherproof seams. Allow to fully cure before stressing joints.
  • - Rivets, screws, bolts, or clamps can also secure multi-layer polycarbonate assemblies.
  • - Use gaskets between sheets to allow for thermal expansion and prevent buckling.

Maintenance and Care

Polycarbonate sheets are designed for durability, but proper care and maintenance is still required to keep them looking their best. Here are some tips for cleaning and protecting polycarbonate:

Cleaning

  • - Use mild soap and water to clean polycarbonate sheets. Avoid harsh cleaners or abrasive pads that could scratch the surface.
  • - For tougher dirt or grime, isopropyl alcohol can be used sparingly. Test on a small area first. 
  • - Never use acetone, benzene, gasoline, or similar solvents on polycarbonate as they can damage the material.
  • - Rinse well with clean water after cleaning. Dry with a soft cloth or chamois to prevent water spots.

Protection 

  • - Apply a UV-resistant polycarbonate sealant or coating to protect against sun damage and discoloration over time. Reapply as needed.
  • - Consider adding an anti-static coating to prevent dust buildup through static cling.
  • - If the sheets will be exposed to chemicals, apply a chemical-resistant coating for added protection.
  • - Use plastic sheets or plywood to cover the polycarbonate when painting or construction nearby to prevent damage from paint splatter or debris. 

Lifespan

  • - With proper installation and care, polycarbonate sheets can last over 10 years. Their lifespan depends on the quality, thickness, and exposure levels. 
  • - Signs of aging include yellowing, reduced light transmission, and reduced impact resistance. At this point replacement should be considered.
  • - Avoid exposing polycarbonate to excessive heat, sun, or moisture to maximize its usable lifespan.
  • Regular cleaning and reapplication of protective coatings allows polycarbonate sheets to maintain their clarity and performance for years before needing replacement. Handle them with care to get the most value out of these durable plastic sheets.

Polycarbonate Sheet Projects

Polycarbonate sheets open up a world of possibilities for DIY projects and commercial applications. Here are some ideas to spark your creativity:

DIY Ideas

  • - Greenhouses - Polycarbonate is ideal for greenhouse roofing and walls. It lets in sunlight while insulating against heat loss. Build a hobby greenhouse or solarium.
  • - Skylights - Cut and install polycarbonate panels as skylights to brighten up any dark room. Great for basements, garages, and sheds.
  • - Storm windows - Make removable storm windows using polycarbonate sheets for insulation. Just insert into window frames during winter months.
  • - Sneeze guards - Use clear polycarbonate sheets to create partitions and barriers as sneeze guards in stores and restaurants.
  • - Furniture - Polycarbonate works great for tabletops, desk surfaces, shelves, and cabinet doors. Cut, drill, and polish to create custom furniture.
  • - Decor - Make abstract wall art, shadow boxes, and decorative dividers with textured or colored polycarbonate sheets. Backlight for special effects. 

Commercial Applications

  • - Roofing - Polycarbonate roofing is extremely durable against weather, impact, and UV rays. Used for industrial buildings, arenas, pools, and patios.
  • - Machinery Guards - Clear polycarbonate panels surround machinery to protect operators while maintaining visibility. Used in factories, shops, and warehouses.
  • - Signage - Backlit polycarbonate sheets create vivid and durable signs and displays. Used for businesses, museums, transportation hubs, events, and advertising.
  • - Windows - Shatter-resistant polycarbonate window glazing can withstand severe storms and forced entry. Used in schools, gas stations, correctional facilities, and public buildings.
  • - Riot Shields - Extremely strong polycarbonate sheets are bullet, fire, and impact resistant. Used for riot shields, armored vehicles, and protective barriers.
  • The possibilities are endless! Polycarbonate offers the clarity of glass with 200 times the impact resistance.

Safety Considerations When Working with Polycarbonate Sheets

Polycarbonate sheets offer many benefits, but there are some safety considerations to keep in mind when working with this material.

Chemical Resistance

While polycarbonate has excellent impact resistance, it has limited chemical resistance. Strong alkaline solutions such as ammonia and bleach can damage polycarbonate over time. Acetone, methyl ethyl ketone, and some hydrocarbons can also degrade polycarbonate. Check chemical compatibility before exposing polycarbonate sheets to cleaners, paints, or other chemicals.

Fire Rating

Polycarbonate itself is flammable and will burn if exposed directly to flames. However, some grades are available with a fire-retardant additive to achieve a UL94 V-0 fire rating. This makes polycarbonate suitable for interior glazing applications. Be sure to check the fire rating before installation.

Handling Precautions

When moving and installing polycarbonate sheets, wear gloves to prevent scratches and cuts from sharp edges. Polycarbonate is more flexible than glass but can still crack if bent excessively during handling. Avoid dragging sheets across rough surfaces. Carry large sheets vertically with helpers. Polycarbonate is also sensitive to high temperatures, so avoid prolonged exposure to heat sources during storage and installation.

Always follow safety practices like wearing goggles when cutting polycarbonate sheets to avoid eye injuries from flying debris. Work in a well-ventilated area and wear a dust mask when cutting polycarbonate. With proper handling precautions, polycarbonate is a safe material for DIY projects and professional installations.