Lab Testing

Lab Testing

Extensive lab testing has been performed to ensure that StonePly stands up to the extraordinary claims made about it. Get the detailed lab results here.

StonePly Testing By Independent Laboratories

StonePly is committed to producing the finest quality. As the world leader in natural stone/honeycomb composite panels, StonePly observes rigorous quality control procedures and testing. Owners and specifiers receive the peace of mind that comes from knowing StonePly has been subjected to testing well beyond the code minimum. Testing is performed at both independent national laboratories and universities as well as StonePly's own research and manufacturing facilities.

General Testing

Tensile Bond Marble faced StonePly tested per ASTM D297 standard test for flatwise tensile strength of sandwich constructions after 130 heat and cool cycles 272psi (39,168 psf) stone splitting indicating adhesive bond strength greater than the stone strength for marble
333psi (47,952psf) for granite
Positive and Negative Wind loads ASTM E330 Tested to pressures in excess of 180 psf. (245 mph wind) No delamination or disengagement. ASCE 7-98 results vary based on height, location, etc.
Salt Spray Resistance ASTM B117 300 hours. No deleterious effects.
Freeze/Thaw ASTM C67 Passed. 100 cycles. No checking, delaminating, cracking or splitting.
Water Resistance ASTM D2247 Passed. No deleterious effects after 120-day exposure.
Mildew/Fungus Resistance ASTM D3273 Passes. Tested with both granite and marble.
Water Penetration ASTM E331 Passed. No water penetration to the innermost plane of the wall.
Large Missile Impact Test ASTM 1996-05B Specifications for Performance of Exterior Windows, Curtain Walls, Doors and Impact Protective Systems Impacted by Windborne Debris in Hurricanes Passed. A weighted 2x4 was fired at the StonePly panel at 50 fps. There was no penetration
Accelerated Weathering ASTM G53 2000 hours. No deterioration.
Air and Water Infiltration ASTM E 283-7 Passed
Absorption - Freeze/Thaw Panels soaked in water @ 20 °C for 4 days, then placed at -10 °C for 2 hours and +20 °C for 2 hours. 100 cycles. No delamination or failure.
Uniform Static Deflection ASTM E 330-02 Standard Test Method for Structural Performance of Exterior Windows, Doors, Skylights and Curtain Walls by Uniform Static Air Pressure Difference. After three years of exposure to two different climates, three panels were tested under uniform static air pressure at 70 psf (approx. 165mph wind) and 105 psf to test structural performance. No attachment or panel failure.
Static Pressure ASTM E 330-00 Standard Test Method for Structural Performance of Exterior Windows, Doors, Skylights and Curtain Walls by Uniform Static Air Pressure Difference. Static Pressure tests were performed to determine if it met the performance requirements for a category 5 hurricane force winds. The panel was tested at 160 psf. All the panels tested met or exceeded requirements.
Cyclic Pressure Loading ASTM E 1886-05 Standard Test Method for Performance of Exterior Windows, Curtain Walls, Doors, and Impact Protective Systems Impacted by Missile(s) and Exposed to Cyclic Pressure Differentials To test repeated positive and negative loads, over 4,500 positive and negative pressure cycles were applied at ±70 psf. (70psf is = 165mph winds)
(psf to mph conversion factors vary based on height, location, etc.)
Flexural Strength Modified ASTM C880 Standard method for determining flexural strength of dimension stone Average wet specimen tested 2,379psi
Freeze Thaw Modified ASTM C666 "Standard test method for resistance of concrete to rapid freeze thaw" Average flexural strength 1996psi after 100 freeze thaw cycles
Hard Body Impact From the "Code of practice for design of non-loading bearing external vertical enclosures to buildings". The test methods in BS 8200: 1985 measure the resistance of the specimen test wall to soft and hard body impact. Test is conducted on front face and side face of panel. No damage: Passed
Tested to 10 Nm
Modulus of Rupture Modified ASTM C99 Average wet specimen tested 3,073psi
Bond Strength Modified ASTM C482 "Standard test for bond strength" 333psi or 47,952psf
Linear Thermal Expansion ISO 10545-8 tested from room temperature to 100°C 12.53 X 10-6 per °C
Accelerated Weathering in Acid Bath 100 cycles of freeze + heat. -10 to 170 degrees F while partially submerged in a 4ph sulphurous acid solution. Less than 11% reduction in flexural strength. No significant difference in load deflection of exposed vs. not exposed specimens.
Temperature Cycling Panel 42" by 58" exposed to 130 cycles rapid heating and cooling from 140 to 65 degrees F No damage or bowing recorded 272psi tensile bond strength
Fastener Pull Out Strength Self-drilling #8 screws by 1/2" long 97lbs. average per screw
Deflection 24" X 34" Panel center loaded with 1,600lbs. Supports placed at 34" Deflection was less than .032"

Panel Weight and Thickness

ComponentStandard (in)Metric (mm)
Panel Weight 3.5 lbs/ft2 18 kg/m2
Nominal Thickness 9/16" | 15/16" 14 mm | 24 mm
Standard Panel Size
(made to order)
48" x 96" (4'x 8')
(Larger panels may be available by special order)
1524 mm x 2845 mm

Panel Performance

R-Value --- 0.05 °F ft2/BTU
Flame Spread ASTM E84 Class A ---
Peel Strength ASTM D1781 34.5 lb-in/lb
Stiffness (EI) ASTM E72 1.27 E+4 lb-in2/ft width
Allowable Bending Moment ASTM E72 1.82E+1 lb-ft/ft width
Tensile Yield ASTM E72 7.34E+3 lb/ft width
Ultimate Tensile ASTM E72 1.04E+4 lb/ft width
Coefficient Of Thermal Expansion ASTM D1237 1.11E-5 in/in/°F
Bond Strength ASTM E-695 370 psi
Ignition Temperature ASTM D1929 900 °F

Wind Load / Span Capacity

Load Uniform lbs/Sq. Ft. 39 95 168 300
Span in inches 48" 36" 30" 24"

Fastener Capacity to Honeycomb

Dow Corning 795 Silicone 20 lbs per square inch
(see manufacturer's recommendations)
#10 ss screws 450 lbs
Rivet ¼" 120 lbs

Fire Testing

"Tunnel Test" ASTM E84 Flame spread 0
Smoke developed 0
Fire Endurance Test Modified ASTM E 119 System remained in place during a 30-minute fire exposure test. Conducted per modified ASTM E119 "Standard Methods of Fire Endurance Tests of Building Construction and Materials."
Diversified Fire Test Modified ASTM E108 Fire hazard = 0
Standard Fire Exposure Test ASTM E119 Fire resistance rating of one-hour and two-hour wall assemblies was not reduced by the addition of the StonePly.
Radiant Heat Exposure Test NFPA 268 Standard Test Method for Determining Ignitibility of Exterior Wall Assemblies Using a Radiant Heat Energy Source Meets requirement for unrestricted fire separation distance. No flaming at 12.5 KW/m2 heat flux exposure. This test is designed to simulate a thermal radiation exposure to an exterior wall from a radiant panel heated to 1600 °F

Read more about fire rating and testing.

Additional Tests

Testing Facilities

The above tests were carried out at the following non-exhaustive list of laboratories:

  • Construction Consulting International
  • Materials Laboratory, University of Maine
  • Wiss, Janney, Elstner Associates, Inc
  • Independent Testing Laboratory
  • Dallas Labs