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Many Villagers now asking this question: Is Longer Better when it comes to a LPS ground rod system?

From AI:
A 20-foot ground rod is better for a lightning protection system because the longer rod provides a more effective connection to earth, reducing ground resistance, especially in less-than-ideal soil conditions. While a standard 8–10-foot rod may suffice in some soil, a longer rod ensures the system can properly dissipate a lightning strike's energy. However, the ideal length depends on soil conditions and a professional risk assessment should be conducted for optimal protection.
Why a longer rod is better:
• Lower Ground Resistance:
A longer rod provides more contact with the earth, which helps to lower the overall resistance of the grounding system, allowing for better dissipation of the lightning's energy.
• Improved Effectiveness:
In sandy or rocky soils, where moisture content is low, a longer rod makes a more significant difference in establishing a reliable connection to the earth.
Factors influencing the choice:
• Soil Type:
The depth and effectiveness of the grounding rod are heavily influenced by the soil's characteristics. In areas with dry or shallow soil, a longer rod is more crucial.
• Risk Analysis:
The best practice is to conduct a risk analysis to determine the appropriate level of protection needed for a structure, which helps in selecting the correct components, including ground rod length.

If you want to make it easy, always ask for a ground rod resistance test at the conclusion of your install and verify that each ground rod has a resistance less than 25 ohms. Higher readings can work, just the rod won't be as effective in the event of a strike. Typically, an installer will use a clamp-on meter to read the resistance to earth ground for each ground rod.