PET Sheeting
Also known as: Polyethylene Terephthalate Film
PET is a widely produced polymer that can be rolled into thin, tough films. When metallised with aluminum it reflects sunlight; when kept diffuse it radiates heat efficiently. Both properties are essential for passive cooling.
Scientific detail
Polyethylene terephthalate (PET) films combine mechanical durability, UV stability and low cost with the optical properties needed for passive cooling: metallised PET achieves solar reflectance above 0.90, while diffuse PET layers provide high thermal emittance across the 8–13 μm atmospheric window. This makes PET a practical substrate for reflective roofs, canopies and reservoir covers at manufacturing scale.
Related terms
Reflective Cooling
Cooling by bouncing sunlight away from a surface before it can be absorbed as heat.
Solar Reflectance
The fraction of incoming solar energy a surface reflects across the sun's spectrum.
Thermal Emittance
How efficiently a surface releases heat as infrared radiation.
Cool Roofs (Reflective Roofs)
Roofs coated or built with high-reflectance materials so buildings absorb far less heat.
Bamboo–PET Composite
A hybrid roofing system combining fast-growing bamboo with reflective PET film.