Roofing

Sizing a Dumpster for a Roof Tear-Off

Roofing is where sizing goes wrong most often, and here it is almost always the same thing: a second layer nobody knew about.

The one number that matters: squares

Roofers measure in squares. One square is 100 square feet of roof surface. A typical north county single-family home runs somewhere between 18 and 30 squares — the post-war ranches at the lower end, the split-levels and later builds higher.

If you do not know your square count, your roofer does, and it is the first thing to ask.

What a square of roofing weighs

The overwhelming majority of residential roofs in north county are composition shingle, which keeps the arithmetic simple — until you find two layers of it.

Composition sizing table

For slate or tile, ignore this table entirely and call us — those are weight jobs that go in small containers with swaps.

The second layer problem

The single most common sizing mistake on roofing work, and it is common here because of when this housing was built.

A great many post-war homes in north county have had a second layer of composition laid directly over the original rather than a full tear-off. It was a normal, permitted practice for decades. It also roughly doubles the tear-off weight.

How to check before you book:

• Look at the rake edge from the ground. A double layer usually shows as a noticeably thicker band at the edge of the roof.
• Look at the flashing and the drip edge. Two layers often sit proud of them.
• Ask your roofer to confirm at inspection. They will know within a minute of getting up there.

If it turns up on the day, call us. A swap mid-job is far cheaper than an overloaded container that cannot legally be hauled, and the crew can keep working while the truck is on its way.

Occasionally there is composition over an original wood shake, which is a third situation again — heavier still, and a genuinely different job.

Storm damage and insurance jobs

A large share of roofing work in this region is storm-driven rather than planned, and it behaves differently.

Missouri gets real severe weather: spring storm season, straight-line winds, hail, and winter ice. Hail in particular drives a lot of insurance-funded roof replacement here.

Practical points:

• Photograph everything before anything moves. The adjuster will want it, and once the shingles are in a container they are gone.
• Do not dispose of damaged material until the claim is settled unless your adjuster has confirmed you can.
• Book early after a major event. Every roofer and every hauler in the region is busy the same fortnight, and containers get scarce.
• Separate the fencing and gutters from the roofing if the same storm took those down — metal has its own route and its own value.

What actually ages roofs here

Worth understanding, because it explains the replacement cycle in this climate.

North county roofs take a genuine beating from both ends of the year: hot, humid summers with strong sun, and winters with hard freezes, ice and freeze-thaw cycling. The repeated expansion and contraction is what loosens seals, curls shingle edges and opens up flashing details, and hail does the rest.

The practical consequences for the container:

• Ice damming at the eaves is a real failure mode here, and where it has been happening the decking and fascia below often need replacing too — that adds tonnage.
• Winter tear-offs are harder to schedule. Shingles are brittle in the cold and crews lose days to weather, so a job that takes two days in October can take a week in January.
• Summer humidity compresses the working day. Crews start early and are often off the roof by mid-afternoon.
• Book the rental period with slack in either season.

Decking is the hidden variable

The other thing that changes a roofing job's tonnage mid-stream.

You do not know the condition of the decking until the shingles are off. On an older roof — especially one that has had ice damming, or a second layer trapping moisture — you can find a significant area of soft or rotten sheathing.

Replacing decking adds real weight: plywood and OSB are heavy, and a large area of it will push a container past its allowance quickly.

Two responses, both fine. Either size up one when you book if the roof is old and you suspect it, or accept that you may need a swap and factor it in. What does not work is overfilling — a container loaded above the rail cannot legally be hauled, and the truck will leave without it.

Placement, canopy and the nail problem

Roofing containers need to sit close to the house, and around here there is one recurring constraint.

Overhead branches. North county has a mature deciduous canopy, and some streets — Calverton Park most obviously, but plenty of others — have branches meeting overhead. Our truck needs roughly twenty-two feet of clear height to raise its bed. On a job with a mid-course swap that has to work twice, not once.

Elsewhere in the area:

• Post-war subdivisions — Florissant, Black Jack, Hazelwood, Bellefontaine Neighbors — generous driveways, straightforward placement.
• Inner-ring streets — Ferguson, Jennings, Overland, Normandy — tighter lots and shorter drives; a 15 yard with a swap is often the workable shape.
• Unincorporated county — Spanish Lake, Old Jamestown — plenty of room, but watch grade, surface and overhead lines at the entrance.

Everywhere: boards go under the rails as standard, and a tear-off sheds an enormous quantity of nails. A magnet sweep of the drive and the street at the end is twenty minutes well spent, and it is the single most common complaint homeowners have about roofing work.