The Importance of Product Testing and Specifications...

Before you begin your bunker project, carefully research your product options and demand specifications. Without this baseline, you have no ability to ascertain what level of quality and performance a manufacturer is committing to. Without specifications, a product description is meaningless.

Determining the Spec...

In many cases, articulating a product's features and benefits comes down to descriptive statements. However, there are definitive product characteristics that can be measured and produce distinct advantages. When introducing Sandtrapper, IVI-GOLF defined a very simple set of principles -- create a durable product that has a framework for stabilizing sand geometries under water flow conditions. Simple yet effective.

To clarify important product characteristics and apply meaning to technical terminology, we performed a range of phyical property test, performed head to head comparisons, and provided additional insight for evaluating bunker liners.






Color Opaque White White White
Weight- oz sq yd/kg sqm (lbs/roll) 16 / .376 (75) 12 / .284 (100) 6 / .142 (70) 11 / .31 (70)
Thickness (mm) 15 14 7 25
Fiber Type Polyester Polyester Polyester Polyester
Binder Cross-Linking Non Soluble Cross-Linking Non Soluble Cross-Linking Non Soluble Cross-Linking Non Soluble
Area Per Roll - 56" (1.42m) 560 ft2 (51.93m2) 1120 ft2 (104.5m2) 1120 ft2 (104.5m2) 560 ft2 (52.02m2)
Area Per Roll - 90" (2.286m) 1125 ft2 (106.8m2) 1350 ft2 (125.42m2) 1800 ft2 (167.22m2) 900 ft2 (83.61m2)
Rolls Per Trailer - 56" (1.42m) 60 55 55 call
Rolls Per Trailer - 90" (2.286m) 38-42 38-42 38-42 call
Trapezodial Tear (MD) / D4533 - LBS 40.5 30.0 24.0 -
Trapezodial Tear (XD) / D4533 - LBS 38.7 31.5 18  
Tensile Strength (MD) / D4632/D751/D5035 - LBS 59.4 51.5 44.5 -
Tensile Strength (XD) / D4632/D751/D5035 - LBS 51.6 50.1 35.5 -
Elongation (MD) / D4632/D751/D5035 - % 87.3 99.3 83.4 -
Elongation (XD) / D4632/D751/D5035 - % 88.9 95.2 135.1 -
Mullen Burst Strength (incl tare) / D3786 - PSI 149 170 118  
Mullen Burst Strength (w/o tare) / D3786 - PSI 98.5 119.5 68 -
Permittivity / D4491 7.22 sec-1 5.92 sec-1 5.94 sec-1 -
Permeability / D4491 - gpm/ft2 567.27 464.88 466.77 -
Transmissivity / D4716 - m2/sec 3.92 x 10-3 1.38 x 10-3 5.46 x 10-4 -


Sandtrapper II

Competitive "Best"

Fiber Thickness 200 denier - polyester 25/45 denier - polyester
Fiber/Binder Ratio 5:3 6:1
Weight 16 oz sq yd 12 oz sq yd
Thickness .78 inches 1.0 inches
Tensile Strength (1) 59.5 lbs 30 lbs
Compression @ 50% 43.5 lbs 25 lbs
Permittivity (2) 7.22 sec -1 3.5 sec -1
Flow Rate 567 gpm / sq ft 250 gpm / sq ft
Transmissivity (3) 3.92 x 10 -3 n/a
UV Resistance (4) >80% @ 1200 hours >75% @ 500 hours
Note 1 - This property is measured by a grab test method. It determines the effective strength of the fabric when subjected to forces that tend to pull the fabric apart. (ASTM-D4632) This is the standard method for determining geotextile design and quality control. A different tensile strength test is called Wide Width Tensile and is used primarily in woven geotextiles. (ASTM-D4595) ------- Note 2 - Permeability or hydraulic conductivity of a geotextile divided by the geotextile thickness. The volumetric flow rate of water per unit cross sectional area per unit head under laminar flow conditions, normal (perpendicular) to the plane of the fabric. (ASTM-D4491) ------- Note 3 - The volumetric flow rate of water per unit width of a geotextile specimen per unit gradient in a direction parallel to the plane of the specimen. (ASTM-D4716) This was performed using (Gradient = 1) and Normal Load (100 psf) ------- Note 4 - A measure of the potential for the deterioration of tensile strength in the fabric due to exposure to ultraviolet light and water. (ASTM-D4355).
SUMMARY COMMENT - The results of standard geotextile tests for products used in bunker settings should be used with caution. Beyond basic measurements, a product’s characteristics or ability to secure bunker sand geometries is unable to be tested with these standard geotextile methods. Nothing is more irrelevant than the standard Apparent Opening Size test, which essentially tests filter qualities and not sand geometries and stability.



Fiber Thickness The thickness of fibers used in a bunker liner material is directly related to its performance. The greater the thickness (denier) of a fiber, the greater its durability, the greater its resistance to tearing, the greater its resistance to compression.
Weight A product’s weight is directly related to the amount of product. In this case, weight is more importantly linked to the amount of binder used in the securing synthetic fibers.
Tensile Strength The tensile strength of a material is measured in terms of the amount of force needed to tear apart the material. In this case the greater the tensile strength, the greater its durability.
Compression Measured in terms of the amount of weight necessary to deflect a material to 50%. In this case, compression is linked to a product’s ability to maintain its three dimensional matrix. The greater the compression strength, the greater its ability to maintain integrity and consistent water flow over time.
Permittivity Measured in terms of water flow across the fabric (perpendicular). In this case, permittivity is directly linked a product’s ability to move water. The greater the permeability, the better the drainage performance.
Flow Rate Measured in terms of volume, flow rate is linked to the product’s ability to move a quantity of water. In this case, the greater the flow rate, the better the drainage performance.




Synthetic Matrix The wide, open synthetic matrix of Sandtrapper allows for increased water flow through and below the sand layer, improving drainage performance, inhibiting washouts.
The tight matrix of competitive products yields the same
performance characteristics as Sandtrapper.
Compression The heavy denier (fiber thickness) and aggressive binders create a matrix that significantly resists compression, producing greater performance, especially over the long haul. A compressed matrix inhibits the flow of water. The greater thickness of competitive liner fabrics without
compression resistance provides greater water moving
performance, even over the long haul.
Durability The aggressive matrix produces a tensile strength of roughly 60 lbs. per sq. in., 200% of competitive products, with zero reported product failures. Products with a scrim layer significantly improves tensile test results but does not prevent snagging or tearing of the non-woven layer. Sandtrapper falls apart
UV Stability UV stability is important when product may be sitting under daylight during pre-installation storage. However, once placed in a bunker and covered with sand, UV stability becomes far less a critical issue. UV stability is typically important in erosion control settings where the geotextile is above the soil and exposed to daylight over many months or years. UV stability is important in bunker liners.
Scrim Layers The addition of a scrim layer improves tensile strength of a material. While this would seem important, a scrim layer causes a negative effect. When a scrim layer is added, surface adhesion is greatly reduced. Without a scrim layer, the fibers “dig” into the bunker surface and provide this adhesion. With large denier fibers (Sandtrapper II), this adhesion is further increased, creating a solid foundation for foot traffic. This is evidenced by a now defunct product, BunkerNet/BunkerAid, which had considerable product performance issues related to the scrim layer with its natural and synthetic product styles. Scrim backing improves short and long term performance.
Apparent Opening Size or
“Sand Passing Through”
The size of openings is irrelevant to bunker liners. More important is the three dimensional matrix that a liner provides. The matrix provides points where bunker sands (which are highly angular) can lock together. As water moves through sand, the matrix prevents sands from becoming lively (creating washouts/slumps). Apparent Opening Size testing (or as BunkerMat refers to as “Sand Passing Through) is relevant when testing geotextiles for dewatering or filtering applications. Large openings allow sand to “pass through” and force the bunker liner to the surface.
Testing Results & Standards Understanding basic product characterisitcs is important, but standard geotextile test results should be used with caution. Some tests do not correlate to valid concerns or performance in bunker settings. Additionally, terminology is often misused which leads to the misrepresentation of test results. Standard geotextile test results for bunker liners are indicative of true product performance.
Reliability Sandtrapper has been “in the ground” since 1998, installed in over 3,000 golf courses worldwide without product failure. Some competitors have existed for just a few short
Competitive products last as long as Sandtrapper.
Water Flow Based on standard geotextile and erosion control tests, Sandtrapper has twice the permittivity and water flow over comparative, competitive products. Competitive products have better drainage characteristics than
Cost The cost of a product is directly related to price and performance. The significantly greater performance and close pricing produces a far better value than competitive products. Sandtrapper is expensive.
Warranty Sandtrapper has a 10-year product warranty, with a “Zero Replacement Cost” assurance for 4 years. Sandtrapper doesn’t support their product with a warranty.
Delivery IVI-GOLF stocks Sandtrapper nationwide and key points worldwide and in the quantities necessary for fast delivery. Many orders, if needed, are shipped on a same day basis. Customer Service doesn’t matter.
Dimensions Sandtrapper is available in 56” and 90” widths. Sandtrapper has narrow rolls, which are more difficult and costly to install.
Installation The cost to replace burned turf and root systems caused by torches doesn’t simplify installation Competitive products suggest cutting with torches, which
simplifies installation.