Viaflex delivers outstanding customer service and high-quality, U.S.-made products – all with an eye on the horizon of earth industries.
Learn More
HDPE and LLDPE geomembrane selection comparison
Selecting a geomembrane requires more than matching a product to a familiar specification. Review the material type, project conditions, liner geometry, chemical exposure, expected movement and installation requirements before finalizing the design.
Two commonly referenced geomembrane specifications are:
The specifications establish minimum, maximum or range-based requirements for selected physical, mechanical and endurance properties. They support manufacturing quality control but do not replace a complete project-specific design basis, chemical compatibility review or qualified engineering evaluation.
Treat this table as a selection guide. Confirm every value against the current specification revision, applicable surface type and project thickness.
The current GRI-GM13 specification covers HDPE geomembranes with a formulated sheet density of at least 0.940 g/cc. The specification addresses smooth and textured materials from 30 mils through 120 mils.
HDPE generally provides a stiffer material structure than LLDPE. This characteristic can support:
GRI-GM13 includes requirements for tensile properties, tear and puncture resistance, carbon black content and dispersion, oxidative induction time, oven aging, UV resistance and stress-crack resistance.
Do not interpret the GM13 designation as a guarantee of service life. The specification establishes manufacturing requirements for the material. It does not account for every load, exposure condition or installation variable that affects long-term performance.
Viaflex HydraLine HD-Series HDPE geomembrane
Viaflex HydraLine HD-Series includes HDPE geomembranes for applications such as landfill caps, waste lagoons, mining containment, ponds and other demanding containment systems. The product family includes HD30 GRI, HD40 GRI, HD60 GRI and HD80 GRI options. Review the applicable product data sheet to confirm thickness, surface configuration and stated properties.
The GRI-GM17 specification covers LLDPE geomembranes with a formulated sheet density of 0.939 g/cc or lower. It includes smooth and textured materials ranging from 20 to 120 mils.
LLDPE generally provides greater flexibility and elongation than HDPE. This behavior can support applications involving:
GRI-GM17 includes requirements for tensile break strength, break elongation, 2% secant modulus, tear resistance, puncture resistance, axi-symmetric break resistance strain, carbon black content and dispersion, oxidative induction time, oven aging and UV resistance.
The maximum 2% secant modulus requirement helps distinguish the flexible material behavior addressed by GM17. The specification also includes a multiaxial strain requirement that provides additional insight into how the material responds to multidirectional deformation.
Do not treat higher elongation as permission to ignore subgrade preparation or panel layout. Flexible geomembranes still require proper support, controlled deployment, appropriate slack management and protection from damage.
Viaflex HydraLine LL-Series LLDPE geomembrane
Viaflex HydraLine LL-Series includes LLDPE geomembranes for liners, caps and covers. The product family includes LL30, LL40 and LL60 options. Use the applicable LL-Series product data sheet to verify the selected material requirements.
Flexibility and settlement
Evaluate expected subgrade movement before selecting the material. HDPE can provide stiffness and dimensional stability when the foundation is well prepared and movement is controlled. LLDPE can better accommodate localized deformation because it is designed for greater flexibility and elongation.
Do not select LLDPE solely because a site appears uneven. Correct the subgrade where practical and address settlement through the design. Do not select HDPE solely because it is commonly used for large containment systems. Match the material behavior to the expected strain condition.
Stress-crack resistance
GRI-GM13 includes a stress-crack resistance requirement for HDPE geomembranes. This requirement addresses a known failure mode affecting certain polyethylene formulations under sustained stress and environmental exposure.
GRI-GM17 does not include the same ESCR requirement. This difference does not mean that an LLDPE geomembrane lacks durability. It reflects the distinct material behavior and test framework associated with LLDPE. Review the manufacturer’s formulation, product data and project exposure conditions before drawing a conclusion about stress-crack performance.
Chemical compatibility
Neither GRI-GM13 nor GRI-GM17 provides a complete chemical compatibility analysis. Identify all liquids, solids, gases and chemical mixtures that may contact the geomembrane. Review:
Request product-specific compatibility information and require qualified engineering review for aggressive or uncertain exposures.
Smooth versus textured surfaces
Both GRI-GM13 and GRI-GM17 cover smooth and textured geomembranes. The specification designation does not determine the surface texture.
Use smooth geomembrane where low friction supports panel handling, drainage or deployment requirements. Consider textured geomembrane where interface friction and slope stability require additional evaluation.
Do not equate asperity height with interface shear strength. The GRI specifications identify this distinction. Determine interface behavior through project-specific direct shear testing such as ASTM D5321 or ASTM D6243 when required by the design or quality plan.
Viaflex HydraFlex HT-Series provides a flexible LLDPE option with a one-sided textured surface for projects where friction and conformability require review.
Do not overlook welding and installation
Material compliance does not guarantee field seam performance. Treat welding and installation as separate design and quality-control considerations.
Require the project team to address:
HDPE and LLDPE geomembranes can be joined by heat-fusion methods, such as hot-wedge welding, when appropriate procedures, equipment, and materials are available.
Geomembrane liner installation and heat fusion seaming by Colorado Lining International
Viaflex supports project execution through U.S. fabrication, custom panel sizes, and heat-fusion fabrication to reduce field seaming where project conditions allow. Installation and inspection services are available through Colorado Lining International, a Viaflex company. Define the required qualifications, testing and documentation in the project specifications.
Use this checklist before approving an HDPE or LLDPE geomembrane:
Yes. GRI-GM13 is the GRI specification for HDPE smooth and textured geomembranes.
Yes. GRI-GM17 is the GRI specification for LLDPE smooth and textured geomembranes.
Neither material is universally superior. Select HDPE or LLDPE based on chemical exposure, stiffness, expected movement and settlement, interface conditions, geometry, thickness and installation requirements.
LLDPE establishes requirements for material behavior including a maximum 2% secant modulus and multiaxial strain testing, like utilized in GRI-GM17. Confirm the actual product data and design conditions before drawing conclusions about flexibility.
No. Texture can support interface friction, but asperity height does not determine site-specific shear strength. Use direct shear testing when required by the design.
No. GRI-GM13 and GRI-GM17 are index specifications focused primarily on manufacturing quality control. Service life depends on material formulation, chemical exposure, temperature, stresses, subgrade conditions, protection, seams and installation quality.
Use GRI-GM13 as the HDPE reference and GRI-GM17 as the LLDPE reference. Then move beyond the specification label. Review the current technical data sheet, evaluate site conditions and define the complete liner system before approval.
Explore Viaflex geomembrane products or submit project requirements via the Viaflex contact portal. Request support for geomembrane selection, custom fabrication, installation planning and inspection requirements.
