When you see a wide price gap between liners that look identical, you are usually seeing the difference between basic retail plastic and a verified, engineered geomembrane. To verify why one material costs more than another, you have to look past the marketing and request a technical spec sheet. A professional-grade liner will have a verified HP-OIT (High-Pressure Oxidative Induction Time) rating, which is the forensic proof that the material contains enough antioxidant stabilizers to survive decades of UV exposure and heat.
Cheaper liners often skip these expensive stabilizers or use recycled "filler" resins that feel the same in your hand but will delaminate or become brittle within a few years. You can't see quality with your eyes, but you can find it on a lab report; if a manufacturer can't provide the data to back up their price, you’re likely paying for a brand name rather than a superior material.
