How Much Do Manhole Covers Weight? What the Figure Means

Most cast-iron manhole covers weigh 80 to 300 pounds, according to Neenah Foundry; its standard 24-inch municipal cover range is about 100 to 150 pounds. Those are cover-only figures. The frame commonly adds 75 to 250 pounds. For exact assemblies, Jim Cox Sales’ March 2026 PAMREX sheets list a 122-pound cover plus a 73-pound frame (195 pounds total) at 24 inches, and a 205-pound cover plus a 188-pound frame (393 pounds total) at 36 inches.

Does the quoted weight mean the lid or the whole assembly?

A generic “manhole cover weight” usually means the removable lid. A product submittal may instead report the frame and cover together, sometimes with a skirt, hinge, lock, or lifting assistance. The noun beside the number controls the answer.

That distinction sounds fussy until a 380-pound line item reaches a lift plan as a 380-pound lid. At an intake desk, I once mistook an application stamp for inspection approval. The paperwork was real; I had assigned it the wrong place in the sequence. Weight records fail the same way. Past ten, I still circle three words before trusting a figure: cover, frame, total.

Here are three cast-iron examples with manufacturer or distributor specifications, rather than a blended “usual” number:

| Product and source | Clear opening / outside frame | Cover only | Frame only | Complete assembly | Material and load statement | |---|---:|---:|---:|---:|---| | PAMREX 24-inch, Jim Cox Sales | 24 in / 33½ in | 122 lb (55.3 kg) | 73 lb (33.1 kg) | 195 lb (88.5 kg) | Ductile iron; 120,000 lb test load | | PAMREX 36-inch, Jim Cox Sales | 36 in / 48 in | 205 lb (93.0 kg) | 188 lb (85.3 kg) | 393 lb (178.3 kg) | Ductile iron; 120,000 lb test load | | Neenah R-1642, Neenah catalog and E.J. Prescott sheet | 24⅛ in / 35⅞ in | Not itemized | Not itemized | 380 lb (172.4 kg) | Heavy Duty; exceeds 16,000 lb proof load |

The R-1642 exposes a second trap. E.J. Prescott describes it as a “26-inch manhole frame and cover,” while Neenah’s drawing gives a 26-inch cover diameter over a 24⅛-inch clear opening. Both descriptions can be accurate. Neither “24-inch” nor “26-inch,” standing alone, is enough to order the casting.

Composite products widen the spread. OPW’s Fibrelite catalog lists its 24-inch FL600BLACK composite cover at 46 pounds, the matching FL600F frame at 17 pounds, and the FL600BLACK-SK12 complete grade-level unit with a 12-inch skirt at 76 pounds. “Assembly” needs a component list as much as it needs a weight.

Which marks and dimensions identify a manhole cover?

Start with the casting, then reconcile it with the installed frame. The useful face or underside marks are the manufacturer name, casting or pattern number, utility legend, load designation, material mark, and any agency ownership mark. A legend such as SANITARY SEWER identifies service; it does not establish fit.

Manufacturer part numbers carry more weight than nominal size. Neenah’s R-1642 number leads to a drawing with a 26-inch cover diameter, 1½-inch section thickness, 24⅛-inch clear opening, 35⅞-inch outside frame diameter, and 6 15/16-inch frame height. The same catalog defines its standard gray iron as ASTM A48 Class 35B and its ductile-iron option as ASTM A536 Grade 80-55-06. Record the actual material specified for the supplied variant.

Measure the installed pieces even when the number is legible. Covers from different families can share a nominal opening and still differ at the bearing surface. Capture:

• cover outside diameter at two directions, especially if wear or damage is visible;
• the smallest clear opening inside the frame;
• frame outside flange diameter and overall height;
• seat diameter, recess depth, and the cover’s bearing-edge profile;
• section thickness and underside rib pattern;
• pick-hole pattern, hinge location, bolt pattern, gasket, venting, and lock details.

Photograph the whole cover, every readable mark, the frame seat, and a tape or rule in the measurement plane. A tape held above a beveled edge can add enough perspective error to turn a plausible replacement into a rocking one.

What makes one manhole cover heavier than another?

Opening size, section thickness, material, and required load performance account for most of the difference. Diameter has a squared effect on plan area: at equal thickness, a 36-inch disk has 2.25 times the area of a 24-inch disk. Real castings add ribs, tapers, pick holes, hinges, and optimized sections, so diameter alone never yields a reliable field weight.

Thickness adds material directly. The Neenah R-1642 drawing’s 1½-inch section is therefore a necessary identification detail, yet it cannot be multiplied by the full disk area as though the casting were a uniform plate. Its underside geometry matters.

Material changes the design options. Neenah specifies ASTM A48 Class 35B gray iron as its standard catalog material and ASTM A536 Grade 80-55-06 for the ductile option. Fibrelite’s FL600BLACK composite lid is 46 pounds at a nominal 24 inches; PAMREX’s 24-inch ductile-iron lid is 122 pounds. That 76-pound gap is a product comparison, not a universal composite-to-iron conversion.

Load class drives the section and reinforcement that engineers must provide. Neenah labels R-1642 Heavy Duty and defines that category as exceeding a 16,000-pound proof-load requirement. The PAMREX sheets state a 120,000-pound test load. Proof load, test load, and traffic class are distinct specification fields; a heavier casting does not automatically carry the higher verified rating.

Solid versus vented construction, watertight gaskets, locks, logos, hinge hardware, and gas struts also move the number. Jim Cox Sales’ 36-inch PAMREX assembly includes dual hinges, a 90-degree blocking system, a lock, and a gas strut. Its 393 pounds describes that configured unit.

What should be inspected if the cover rocks, cracks, or will not seat?

Treat movement, cracking, or incomplete seating as a condition report before treating it as a lifting job. Observe from outside the traffic path. Record whether the cover rocks under load, which edge rises, whether the frame moves with it, and whether the surrounding pavement or concrete has settled or broken away. Isolate the area under the owner’s site-control procedure when the defect could expose users to displacement or collapse.

A cover can rock because grit, asphalt, rust scale, paint buildup, or a damaged gasket interrupts the bearing surface. It can also be the wrong casting, a warped lid, a fractured frame, a worn seat, loose anchorage, or a frame no longer supported evenly by its bedding. A pry bar answers none of those questions by itself.

After the site is controlled and the planned lifting device is attached, inspect the underside ribs, bearing edge, frame seat, hinge, lock, pick holes, and visible anchorage. Do not stand or reach over an unguarded opening to improve the photograph. Cracks, missing metal, frame movement, or a mismatch between the casting number and asset record belong in the work record before cleanup hides the evidence.

What tool and site controls are needed before lifting?

Choose the lifting method from the identified product, its verified cover-only mass, the available lifting points, and the manufacturer’s instructions. Neenah’s catalog safety guidance says to use a lifting device and to protect the back and extremities. A hook or key must match the pick hole. A magnetic lifter works only on a compatible ferrous lid with a surface condition the device permits. Wheeled, hydraulic, or powered lifters keep the load controlled; a cover dolly moves it clear without asking a worker to hold it.

“One-man operable” is a product feature, not permission to hand-lift every cover. Jim Cox Sales applies that phrase to its hinged PAMREX designs, which include blocking or assistance hardware. A loose 122-pound PAMREX lid and its 195-pound assembly remain different handling problems. Use the employer’s lift assessment, trained crew, rated equipment, and product instructions rather than a universal one-person cutoff.

Control the opening before breaking the seal. For work affecting a road or site roadway open to public travel, the Federal Highway Administration’s MUTCD Part 6 makes temporary traffic control part of utility and maintenance planning; the arrangement depends on road users, duration, physical constraints, and proximity to traffic. A cone beside an exposed hole is not a complete plan.

OSHA’s 29 CFR 1910.146(c)(5)(ii), for applicable general-industry permit spaces, requires unsafe conditions to be eliminated before an entrance cover is removed and the opening to be promptly guarded with a railing, temporary cover, or other barrier. Under that rule, entry begins as soon as any body part crosses the opening’s plane. Construction contractors should apply OSHA 1926 Subpart AA where it governs. Removing a lid and entering the space are separate authorized activities.

Which replacement details prevent an incompatible order?

The safest order starts as a field-to-submittal match. Weight is one check among several; Neenah’s catalog cautions that casting weights vary and directs users to the manufacturer for current figures. Follow this sequence:

1. Secure the site and identify the asset owner, utility service, traffic exposure, and governing agency specification before opening anything.
2. Capture every casting mark and photograph the cover in place. After a controlled lift, capture the underside, frame seat, hinge, locks, gasket, and pick holes.
3. Measure the cover, clear opening, mating seat, recess, section, outside frame, frame height, and attachment geometry. Keep nominal and measured dimensions in separate fields.
4. Match those records to a current manufacturer drawing and submittal. State whether the order is cover only, frame only, or a configured assembly; include manufacturer part number, material grade, load class or test requirement, legend, venting, sealing, locking, hinge orientation, and approved finish.

Ask the supplier to confirm compatibility with the existing frame in writing. Where the manufacturer requires a matched set, replace the frame and cover as that set and include bedding, anchorage, elevation, and pavement restoration in the work scope. Field-fit verification and final seating inspection follow installation. A purchase approval shows what was authorized; it cannot show that the finished casting sits flush.

How should cover condition and handling be managed over its service life?

Give each access point an asset record that survives contractor changes. Keep the manufacturer and part number, all measured dimensions, cover-only and assembly weights, material, load requirement, required lifting tool, traffic-control plan reference, confined-space classification, photographs, and the latest inspection status. One page is enough if the fields are disciplined.

Update the record whenever the cover is opened, struck, paved around, reset, or replaced. Log rocking, cracks, seat wear, corrosion, gasket or lock condition, frame support, and the corrective action. Inspection frequency should come from the asset owner, authority, and manufacturer because exposure differs sharply between a locked landscaped vault and a wheel-path casting.

At closeout, clean the bearing surfaces by the approved method, seat the cover fully, engage its lock or hinge restraint, and verify that it stays stable before removing barriers. Keep the work order, installation record, and inspection result as separate statuses. Eleven years of permit files have made me stubborn about sequence: “installed” still leaves the final seating check open.

Frequently asked questions

Can one person lift a manhole cover?

One person should move a cover only when the manufacturer’s design, the employer’s lift assessment, and the rated tool support that method. Jim Cox Sales calls its hinged, assisted PAMREX covers one-man operable using standard tools. That claim does not apply to an unidentified loose casting or justify lifting it by hand.

How much does a 24-inch manhole cover weigh?

Neenah Foundry gives about 100 to 150 pounds for a standard 24-inch municipal cover. One exact example, Jim Cox Sales’ 24-inch PAMREX, weighs 122 pounds for the lid, 73 pounds for the frame, and 195 pounds for the complete assembly. Check the part-specific sheet before planning a lift.

How heavy is a 36-inch manhole cover?

Neenah Foundry’s traffic-rated 36-inch range is 180 to more than 400 pounds for covers. Jim Cox Sales lists its ductile-iron 36-inch PAMREX lid at 205 pounds, its frame at 188 pounds, and the complete hinged assembly at 393 pounds. Design and load requirements explain the wide range.

Why are manhole covers heavy?

Manhole covers need enough material and engineered section strength to resist their specified service loads, remain seated, and survive traffic exposure. Size, thickness, ribs, material, hinges, seals, and locks all affect mass. Neenah’s R-1642 is Heavy Duty and exceeds a 16,000-pound proof-load requirement; its assembly weighs 380 pounds.

What is a manhole-cover weight in kilograms?

Convert pounds to kilograms by multiplying by 0.453592. A 100-pound cover is 45.4 kilograms, while a 150-pound cover is 68.0 kilograms. Jim Cox Sales publishes exact metric values for the 36-inch PAMREX: 93.0 kilograms for the cover, 85.3 kilograms for the frame, and 178.3 kilograms total.

How much does a cast-iron manhole cover weigh?

Neenah Foundry reports that most cast-iron manhole covers weigh 80 to 300 pounds. Its general range includes different diameters, duty levels, and designs, so it cannot identify a particular lid. Use the casting number and manufacturer sheet to separate cover-only weight from the heavier frame-and-cover assembly.

How do I identify a cover before replacing it?

Photograph the manufacturer, casting number, utility legend, load and material marks, then measure the cover diameter, clear opening, seat, recess depth, section thickness, outside frame, hinge, bolts, gasket, and pick holes. Match those details to a current manufacturer drawing and obtain written confirmation that the replacement fits the installed frame.