HDPE geomembrane comes in a range of thicknesses, and picking the right one is the single biggest decision on a lining job. Too thin and you risk punctures and failure; too thick and you’re paying for material you don’t need. Here’s how to choose.
The common thicknesses
- 0.5–0.75 mm — light-duty lining: decorative ponds, temporary containment, short-life applications.
- 1.0 mm — a common all-rounder for irrigation reservoirs, farm lagoons and landscape water features.
- 1.5 mm — the workhorse for most containment: lagoons, canals, larger ponds and general civil works.
- 2.0 mm — higher-duty containment, exposed applications, and where puncture risk or hydraulic head is greater.
- 2.5–3.0 mm — heavy-duty: landfill base and cap, chemical and fuel secondary containment, demanding exposure.
What actually drives the choice
Thickness is set by the duty, not by preference. The main factors are the subgrade (rough or stony ground needs thicker liner or a geotextile cushion), the hydraulic head (deeper water = more pressure), exposure (UV and temperature swings favour thicker, and a textured surface on slopes), design life, and any project specification the consultant has issued.
Smooth vs textured
On flat bases, smooth HDPE is standard. On slopes and vertical faces, textured HDPE adds friction so the liner and any cover soil stay put. Many jobs use both.
Don’t forget the cushion and the welds
A liner is only as good as what’s under and around it. A geotextile cushion protects against puncture from below; welded (not glued) seams are what make the whole thing watertight. That’s why we weld and leak-test every seam.
Still not sure?
We’ll recommend the right grade after a quick look at your application and site. See the full HDPE liner range, or explore where it’s used in lagoon lining and HDPE liner installation.