How to Check an Overhead Service Drop Before You Set a Ladder

Why this matters

The wires that bring power from the pole to an older house are often the oldest electrical equipment on the property, and they run exactly where roofers, gutter crews, painters, window cleaners and tree crews work: across the eave, over the porch roof, through the front-yard maple. A ladder that touches one, or a 20-foot length of aluminum gutter swung into one, can kill the person holding it. The check takes three minutes from the ground before any ladder comes off the truck. It is the one step on these jobs with no second chance.

Safety first. Treat every overhead conductor as energized and uninsulated. The covering on a service drop is weatherproofing, not rated insulation, and the neutral messenger it hangs from is often bare. Nobody touches a drop, a mast or a conductor with a hand, a tool, a ladder or a pole to "check" it. If a line is down, arcing, or touching a gutter, tree or roof: keep everyone at least 35 feet back, call the utility's emergency line and 911, and do not work.

What this card covers. Recognizing the drop and its attachment, reading its condition, and planning the ladder set around it. What the utility owns and what the homeowner owns. It does not cover electrical repair of any of it, which belongs to the utility or a licensed electrician. Ladder setup itself is owned by the library's ladder cards.

The parts, from pole to house

• Service drop. The overhead conductors from the utility pole to the house. On most older houses, a twisted bundle (triplex): two insulated hot conductors wrapped around a bare or lightly covered neutral messenger that carries the weight.
• Point of attachment. Where the drop is fastened to the house: a bracket on the wall or fascia, an insulator knob on the siding, or a clamp on a mast.
• Service mast. A steel pipe rising through the roof or up the wall to lift the attachment point high enough for clearance. Older masts are often thin-wall conduit that was never meant to take a drop's pull.
• Weatherhead. The hooded fitting at the top of the mast or cable where conductors enter. The drip loops below it hang down so water runs off before it enters.
• Service entrance cable or conductors. From the weatherhead down to the meter base.

Who owns what. The National Electrical Code defines the service point as where the utility's conductors meet the premises wiring, and the utility decides where that point is. On most residential services the utility owns the drop and the meter, and the homeowner owns the mast, the weatherhead, the attachment bracket in many cases, the service entrance conductors and the meter base. That split varies by utility tariff, so a damaged mast on one street is the homeowner's electrician's job and the same damage on the next is the utility's. The practical answer is the same either way: you report it, and you do not fix it.

The check, step by step

1. Find the drop before you unload. Stand at the street and trace the conductors from the pole to the house. Note every pole that feeds the property; corner lots and long driveways sometimes have two spans and a mid-yard pole. Why first: the ladder set, the material drop zone and where you park all depend on it. Skip it and the first time anyone looks up is with a ladder already in their hands.

2. Identify the attachment point and how it is held. Bracket on the wall, knob on the siding, or mast through the roof. If a mast, note whether it has a guy wire or brace and whether it passes through a roof boot. Why: a mast through the roof puts the drop's live end right where a roofer works, often within a few feet of the shingles. Skip it and a roofer works the eave "away from the wires" while standing next to the mast.

3. Read the condition from the ground. Look for: insulation cracked, peeled or hanging in strips; a drop sagging so low it crosses the roof surface or touches a gutter; conductors rubbing a tree limb or the fascia; a mast leaning, bent or pulled away from the wall; a weatherhead cracked or missing its hood; drip loops missing so water runs into the head; brackets pulling out of rotted fascia. Binoculars help. Photograph each finding from where you stand. Why: a degraded drop is closer to energized bare metal than a sound one, and a leaning mast can fail when a ladder or a limb loads the area around it. Skip it and you set up beside a mast that is already halfway to failing.

4. Estimate clearances by eye, never with a pole. Compare the drop's lowest point over walkways, driveways, roofs and pools against things of known height: a 7-foot garage door, a 9-foot first-floor ceiling line, a gutter at a known eave height. Rough figures in the code tables, as adopted by your jurisdiction, give you a sense of "low": the NEC's overhead service conductor clearances (Section 230.24 in the 2020 and 2023 editions) call for 12 feet over residential driveways at 300 volts to ground or less, and generally 8 feet 6 inches above a roof, with exceptions down to 3 feet on steeper roofs and 18 inches where conductors only pass over the overhang near the mast. The utility's own drop is governed by the National Electrical Safety Code and its tariff instead, with figures close to these. Over a pool, the NEC Article 680 overhead-conductor table sets about 22 1/2 feet above the water for insulated service cables (in Section 680.9 of recent editions; check your adopted edition's numbering). Why: you are not enforcing the code, you are recognizing that a drop is lower than anyone expected. Skip it and a pool crew with a 24-foot skimmer pole, or a roofer standing on a low-slope porch roof, finds the clearance by touch.

5. Draw your own 10-foot line. For work by people who are not qualified electrical workers, OSHA's general-industry standard (29 CFR 1910.333(c)(3)) sets a minimum of 10 feet between any part of the body or any conductive object and an overhead line of 50 kV or less, unless the line is de-energized and grounded or guarded by the utility. On construction work the employer must keep employees from contact by de-energizing or guarding the line (29 CFR 1926.416(a)(1)), and portable ladders used where they could contact energized conductors need nonconductive side rails (29 CFR 1926.1053(b)(12); 1910.333(c)(7) on the general-industry side). The 10 feet includes the ladder, the tool, the gutter length and the tree limb you are cutting. Mark the zone on your sketch. Why: the hazard is the long object, not the hand. Skip it and you plan the ladder outside 10 feet and carry a 20-foot downspout section through the zone.

6. Plan the ladder set and the raise outside it. A fiberglass ladder, set where neither the ladder nor anything you will handle from it can enter the zone. Raise and lower it where nothing overhead sits within its own length plus 10 feet, as a shop default: a ladder that kicks out or is walked up sweeps an arc as long as itself. Carry ladders and long materials horizontally and low. Why: most ladder contacts happen while raising, lowering or moving, not while standing on it. Skip it and the set is fine and the raise is the accident.

7. If the work needs to be inside the zone, call the utility first. Ask for the line to be de-energized or covered with insulating line hose and blankets (a cover-up). Utilities do this for contractors, often on a few days' to a couple of weeks' notice. Tree work within the zone of any line is for a line-clearance tree crew working under 29 CFR 1910.269, not a general tree crew. Why: no technique makes a ladder inside 10 feet of an energized line acceptable for an unqualified crew. Skip it and the job gets done "carefully," which is the shape of most fatal contacts.

8. Brief the crew, then write it down. At the truck, point at the drop, name the zone and the ladder positions, and name who watches long materials. Then put the condition findings on the job record and tell the customer: what you saw, who owns it, and who to call. Why: a crew member who arrives after the walk-around, or a helper on day two, has not seen the drop. Skip it and the plan lives in one person's head.

Worked example: a gutter replacement on a 1952 house

A gutter crew is replacing the front run on a two-story house: 38 feet of seamless gutter at an eave 19 feet above grade, using a 28-foot fiberglass extension ladder.

Steps 1 to 3. The drop runs from a pole off the front-left corner of the lot to a mast that rises through the roof about 4 feet from the left end of the front eave. The mast leans visibly toward the street, the roof boot around it is cracked, and the drop's insulation is peeling in strips for about 3 feet near the weatherhead. The drop heads away from the house toward the pole, so it does not cross the rest of the front.

Step 4. The drop's lowest point over the driveway looks to be about 11 feet, against the 7-foot garage door. That is below the 12-foot figure for driveways in the tables above. A delivery truck could reach it.

Step 5. Measuring along the eave from the left end, the mast sits at 4 feet. Ladder positions and the gutter itself must stay 10 feet clear, so anything from the left end to about 14 feet (4 plus 10) is inside the zone. That leaves 24 feet of the 38-foot run (38 minus 14) outside it.

The problem. Seamless gutter goes up as one piece. Lifting a 38-foot length along the eave puts its left 14 feet inside the zone, within reach of a mast that is already leaning. Splitting the run into two pieces with a seam at 14 feet would keep the crew clear but gives the customer a joint they did not buy.

Step 7. The crew lead calls the utility and requests a cover-up on the drop. The utility schedules it 5 business days out and also opens a ticket for the low clearance over the driveway.

What the crew does today. The side and back runs, which are nowhere near the drop. The front run is rescheduled for the cover-up day, and the customer chooses that over the seamed option after hearing both.

Step 8, the note. "Overhead service mast at front left leans toward street; roof boot cracked; drop insulation deteriorated near weatherhead. Drop sags to about 11 ft over driveway (estimated). Utility notified for cover-up and low clearance; mast and roof boot are typically the homeowner's, recommend a licensed electrician. Front gutter scheduled for cover-up day." The office copies the utility ticket number onto the job.

On cover-up day, the resume step carries its own check. Before the ladder goes up, the lead confirms from the ground that the line hose covers the drop from the mast to beyond the zone, that the utility crew has said the cover-up is complete, and that nothing has shifted since. A cover-up protects against incidental contact; it does not make the drop something to lean on, and the crew still keeps the gutter off it.

What would have changed the answer. If the drop attached to a wall bracket at the far end of the house, the front run would have cleared 10 feet everywhere and gone up that day. If the mast were sound and only the driveway clearance were low, the work would proceed with a utility ticket for the clearance and the truck parked on the street.

If contact happens

Do not touch the person or the ladder; you become part of the circuit. Call 911 and the utility. Keep everyone back at least 35 feet; the ground around a fault can be energized. If a vehicle or lift is in contact, those inside stay inside unless there is fire; if they must leave, they jump clear without touching the vehicle and the ground at the same time, land with feet together, and shuffle away without lifting their feet. Once the utility confirms the line is dead, start first aid and CPR if trained, and keep the person still until EMS arrives.

References

• See related: Overhead Utility Lines + Clearances Reference; Ladder Safety
• See related: How to Set and Tie Off an Extension Ladder So It Cannot Move
• OSHA 29 CFR 1910.333(c)(3) and (c)(7) (general industry), 29 CFR 1926.416(a)(1) and 1926.1053(b)(12) (construction), 29 CFR 1910.269 (line-clearance tree trimming)
• NFPA 70, National Electrical Code, Article 230 and Article 680, in the edition your jurisdiction has adopted; National Electrical Safety Code for the utility's drop