By A direct lightning strike carries tens of thousands of amps. Without a safe path to earth, that energy travels through a building’s structure, wiring and people — causing fires, equipment damage and injury. A lightning protection system (LPS) gives the strike a deliberate, low-resistance route from the highest point of the structure straight down to the ground, keeping the building and its occupants safe. This guide explains the parts of an LPS, the main types, and what drives the cost.
The three parts of a lightning protection system
Every LPS, simple or advanced, has three functional parts:
- Air termination (the “lightning conductor” or “lightning arrester”) — the point(s) at the top of the structure that intercept the strike. This can be a simple Franklin rod or an advanced ESE air terminal.
- Down conductor — the cable that carries the current from the air terminal down the building to earth.
- Earth termination — the earthing system (electrodes) that dissipates the current safely into the ground.
If any part is undersized or poorly bonded, the whole system is compromised — which is why design and installation matter as much as the products.
Types of lightning protection
- Conventional (Franklin rod / mesh) — one or more air rods, or a mesh cage, connected by down conductors to earth. Proven, economical, and specified by IS/IEC standards for most buildings.
- Early Streamer Emission (ESE) — an active air terminal that launches an upward leader earlier, giving a larger protective radius from a single mast. Useful for large or open sites; designed to NFC 17-102.
Compare conventional and ESE options → Ashlok Lightning Protection Systems and Conventional Lightning Protection
Do I need lightning protection for my building?
A risk assessment considers the building’s height, location, ground flash density, occupancy and contents. Tall structures, isolated buildings, factories, warehouses, hospitals, schools and sites with flammable or sensitive contents are the usual candidates. A qualified assessment (per IS/IEC 62305) tells you whether protection is required and to what level.
Lightning protection and surge protection work together
An LPS handles the direct strike. But lightning also induces voltage surges on power and data lines that can destroy electronics even without a direct hit. Complete protection pairs the external LPS with internal surge protection devices — the two are complementary, not alternatives.
What affects lightning protection system cost?
“Lightning protection system cost” depends on:
- Type — conventional vs ESE,
- Building size and height (number of air terminals and length of down conductors),
- Earthing required to achieve a low earth resistance, and
- Site conditions and installation access.
Because every structure is different, cost is quoted per site. Request a lightning protection quote from Ashlok →
Frequently asked questions
What is the difference between a lightning conductor and a lightning arrester? In common use they refer to the air termination at the top of the building. Note that a surge arrester is different — it protects electrical lines from induced surges, not direct strikes.
Is ESE better than a conventional Franklin rod? ESE can cover a larger area from a single mast, which suits big or open sites. Conventional systems are proven and economical for most buildings. The right choice comes from the site risk assessment.
Does a lightning protection system need earthing? Yes — the earth termination is essential. A low, stable earth resistance is what lets the strike dissipate safely.
How often should it be inspected? Periodically, and after any known strike, to confirm connections and earth resistance remain within spec.
Will it protect my electronics? The external system protects the structure; add surge protection devices to protect wiring and electronics from induced surges.
Ashlok designs, supplies and commissions conventional and ESE lightning protection across India. Explore lightning protection systems →