What does a weatherhead do?

It keeps rain and debris from entering the top of the service entrance conduit where the utility drop connects to the building's electrical wires.

Who is responsible for the weatherhead — the homeowner or the utility?

The weatherhead and service mast are typically the homeowner's responsibility. The utility owns the drop wires that connect to them but does not maintain the weatherhead itself.

Do I need a permit to replace a weatherhead?

Usually yes. Service entrance work involves high-current conductors near energized utility lines, so most jurisdictions require a permit and inspection for weatherhead replacement.

Can I replace a weatherhead myself?

It is not recommended for homeowners because the utility drop remains energized even when the main breaker is off. An electrician coordinates with the utility to ensure safe working conditions.

Weatherhead — Service Entrance Cap for Electrical Mast

Q: Can a damaged weatherhead cause electrical problems?

Yes. Water entering the conduit can corrode connections, damage insulation, and eventually cause faults at the meter base or panel. A cracked or missing weatherhead should be replaced promptly.

A weatherhead is a curved fitting at the top of a service entrance conduit that prevents rain from entering the electrical mast where utility wires connect.

Weatherhead diagram — labeled parts and installation context

What It Is

A weatherhead, also called a service entrance cap or service head, sits at the top of the riser conduit where the utility company's overhead service drop connects to the homeowner's service entrance conductors. Its downward-facing opening allows the conductors to exit the conduit while the curved hood directs rain, snow, and debris away from the conduit interior. The conductors typically form a drip loop below the weatherhead — a deliberate downward arc that lets water run off the wire insulation before it can track back into the fitting.

The weatherhead is part of the overhead service entrance assembly that also includes the mast pipe (usually 2-inch or 2-1/2-inch rigid metal conduit), the meter base, and the main disconnect or service panel. NEC Article 230.54 requires that service heads be located above the point of attachment of the service drop, and the conductors must exit the head in a downward direction to prevent water entry. The weatherhead is one of the few visible points where the utility side meets the customer side of the electrical system.

Types

Clamp-on weatherheads slide over the outside of the conduit and are secured with a set screw or compression band. They are common on EMT (electrical metallic tubing) and thin-wall conduit installations. Threaded weatherheads screw directly onto the end of rigid metal conduit (RMC) or intermediate metal conduit (IMC), providing a more secure mechanical connection suitable for heavy service masts.

Combination heads include a built-in strain-relief clamp that grips the service entrance cables as they pass through the fitting, preventing the cable weight from pulling on the connections inside the mast. Materials include die-cast aluminum, which is lightweight and corrosion-resistant, and thermoplastic (PVC), which is used on PVC conduit risers. Sizes match standard conduit diameters — 1-1/4 inch, 1-1/2 inch, 2 inch, and 2-1/2 inch are the most common residential sizes.

Where It Is Used

Weatherheads are used at the top of overhead electrical service entrances on residential and commercial buildings. They are mounted where the service mast penetrates the roofline or eave, extending at least 12 inches above the roof surface per most utility requirements, and where the utility drop wires attach to the building's conductors.

In areas where overhead service is standard, virtually every home with utility power has a weatherhead. Underground service entrances bypass the weatherhead entirely because the conductors enter the meter base from below grade rather than from an overhead drop. When a home converts from overhead to underground service, the weatherhead, mast, and drop are removed as part of the project.

How to Identify One

Look at the top of the electrical mast on the exterior of the building, usually near the roofline on the utility-facing side. The weatherhead is the curved or hooded cap from which two or three service entrance conductors emerge and loop downward toward the utility connection point. The hood faces downward, and the conductors arc in a drip loop before connecting to the utility drop at a point of attachment — typically an insulated spool or bracket bolted to the mast or the building.

A weatherhead in good condition has an intact hood with no cracks, the conductors pass through rubber grommets or insulated bushings, and there is no visible corrosion around the conduit connection. A damaged weatherhead may show cracked plastic, missing hood sections, rust streaks running down the mast, or conductor insulation that is frayed or exposed at the exit point.

Replacement

Replacement is needed when the weatherhead is cracked, corroded, missing its rain shield, or no longer sealing against the conduit. Water entering the mast can corrode the service entrance conductors, damage the insulation, and eventually cause faults at the meter base or main panel. Because this work involves the service entrance and close proximity to energized utility conductors — which remain live even when the main breaker is turned off — it typically requires a licensed electrician, a permit, and coordination with the utility company to temporarily disconnect the drop.

The electrician will remove the old head, inspect the mast and conductors for corrosion or damage, install the new weatherhead with the correct conduit connection, and re-form the drip loop. The utility company then reattaches the drop and restores service. Most jurisdictions require an inspection before the utility will reconnect.