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GEM Ground Enhancement Material

Estimate system resistance values for basic grounding system designs and calculate the number of bags of ground enhancement material required with our GEM Calculator. Click Here to try it today!

Ground Enhancement Material (GEM) is a superior conductive material that solves your toughest grounding problems. It is the ideal material to use in areas of poor conductivity, such as rocky ground, mountain tops and sandy soil. GEM dramatically reduces earth resistance and impedance measurements. Furthermore, GEM may reduce the size of the grounding system where conventional methods are unsatisfactory. Once installed, GEM is maintenance-free, not requiring periodic charging or the presence of water to maintain its conductivity. Third-party testing has been completed to verify that GEM conforms to IEC® 62561-7. This standard introduces a benchmark for electrical performance and corrosion of earth enhancement materials that has been absent from the industry to date. nVent ERICO offers GEM Calculator software that provides resistivity values for common GEM applications and can help estimate the amount of GEM required for an installation. It operates in four languages - English, Spanish, French and German - and performs calculations in Imperial or Metric units. The GEM Calculator is available for download on our website at erico.com.


  • Maintains constant resistance for the life of the system once in its set form
  • Performs in all soil conditions even during dry spells
  • Does not require periodic charging treatments or placement
  • Does not require the continuous presence of water to maintain its conductivity
  • Fully sets within 3 days, fully cures within 28 days
  • Does not dissolve, decompose, or leach out with time
  • Non-corrosive
  • Reduces vandalism and theft since conductors are hard to remove from concrete
  • Easy-to-handle 25 lb (11.3kg) bags or buckets
  • Requires only one person to install
  • Exceeds IEC® 62561-7 which sets the benchmark for corrosion, leaching, sulfur content, and other environmental regulations
  • Complies to the U.S. Environmental Protection Agency (EPA) Toxicity Characteristic Leaching Procedure (TCLP), EPA test method 1311
  • Can be installed using trench or ground rod backfill methods


Unit Weight: 25 lb
Part Number Packaging Complies With
GEM25A Bag with handles IEC® 62561-7
GEM25ABKT Plastic bucket with locking lid IEC® 62561-7
Suggested Specifications
Parameter Recommended Values Test Method
Standards Compliance Full compliance to 
IEC 62561-7 EPA Toxicity 
Characteristic Leaching 
Procedure (TCLP), 
test method 1311
Leaching Arsenic < 1.5 mg/L, Barium < 60 mg/L, 
Cadmium < 0.15 mg/L, Chromium < 3.0 mg/L, 
Lead < 1.5 mg/L, Mercury < 0.06 mg/L, 
Elenium < 1.0 mg/L
EC 62561-7
EN 12457-2
Sulfur Content < 2% ISO 14869-1
Resistivity <2 Ω-cm for powder
<20 Ω-cm for mixed and cured material
Compressed powder 
according to ASTM G187-12
Mixed and cured per 
ASTM D991-89
Corrosion Performance For copper-plated earth electrodes, 
the polarization resistance shall be
> 8 Ω x m2 for aggressive environments
For galvanized earth electrodes, 
the polarization resistance shall be
> 7.6Ω x m2 for aggressive environments
IEC 62561-7, Sec 5.5, 
aggressive environment
Flexural Strength 300-450 psi [2070-3100 kPa] ASTM C293
Compressive Strength 100-200 psi [690-1390 kPa] 
after 672 hours curing time
Estimated Linear Feet of Ground Conductor Covering with Each Bag of GEM
Trench Width Total Thickness of GEM
in cm in cm in cm
Inches Centimeters 4 10.2 5 12.7 6 15.2
4 10 3.5 1.0m 2.8 0.8m 2.3 0.7m
6 15.2 9.3 0.7m 1.8 0.5m 1.5 0.4m
8 20.3 7 0.5m 1.4 0.4m 1.1 0.3m
10 25.4 5.6 0.4m 1.1 0.3m 0.9 0.3m
12 30.5 4.7 0.3m 0.9 0.3m 0.7 0.2m
Estimated Bags of GEM for Backfilling Around Ground Rods to a Density of 63.5 lb/ft ³ (1,017 kg/m³)
Diameter of Hole ft m ft m ft m ft m ft m ft m
Inches Centimeters 5 1.5 6 1.8 8 2.4 10 3 15 4.6 20 6.1
4 10.2 2 2 2 3 4 5
6 15.2 3 3 4 5 8 10
8 20.3 5 6 8 9 14 18
10 25.4 7 9 12 14 21 28
12 30.5 10 12 16 20 30 40

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