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 two things: a second layer, or rotten decking under it.

The one number that matters: squares

Roofers measure in squares. One square is 100 square feet of roof surface. A typical house across Blair County runs somewhere between 16 and 28 squares — the older borough houses at the lower end, the post-war and township properties 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

One regional note: slate is not a curiosity here. Pennsylvania has a long slate roofing tradition and older houses in the boroughs genuinely have it. If yours does, the arithmetic changes completely — slate can be five times the weight of composition, and a slate tear-off wants a 10 yard with swaps rather than anything larger.

Composition sizing table

Add a size if the decking is coming off too, and step down to a 10 yard with swaps for slate.

The second layer problem

The most common sizing mistake on roofing work anywhere, and common here because of when this housing was built and re-roofed.

A great many houses across this area have had a second layer of composition laid directly over the original rather than a full tear-off. It was 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 roof edge.
• Look at the flashing and 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 keeps working while the truck is on its way.

Occasionally there is composition over an original wood shake, or over slate, and both are heavier still.

Ice dams and what they do underneath

The local factor, and the reason roofs here often need more than shingles replacing.

Winters against the Allegheny Front produce real ice damming at the eaves — snow melts higher up the roof where the attic is warmer, runs down, and refreezes at the cold overhang. Water then backs up under the shingles rather than running off.

What that means when the roof comes off:

• The eaves are where the damage concentrates. Expect soft decking in the first few feet above the wall line.
• Fascia and soffit often need work at the same time, and that is extra material in the container.
• Repeated freeze-thaw degrades shingles and sealants faster than a milder climate would, so replacement cycles here are shorter than the shingle warranty suggests.
• A second layer makes it worse — trapped moisture between layers has nowhere to go.
• Elevation matters. A property up toward the ridge sees a harder winter than one on the valley floor, and it shows in the decking.

If your roof has had ice dams, assume decking replacement is likely rather than possible, and size accordingly.

Decking is the hidden variable

You do not know the condition of the decking until the shingles are off, and it is the single most common reason a roofing container runs over.

Plywood and OSB are heavy — roughly 40 to 60 pounds a sheet. A roof needing widespread decking replacement can add a ton or more that nobody budgeted for, on top of the shingles.

On older houses here there is a second possibility: plank decking rather than sheet. Dimensional boards laid across the rafters were standard before plywood, and they are considerably heavier again per square foot.

Two responses, both fine:

• Size up one when you book if the roof is old, has had ice dams, or carries a second layer.
• Accept 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 — which costs a day as well as a return trip.

Storm and insurance work

A meaningful share of roofing work here is storm-driven rather than planned — wind, hail and the aftermath of a hard freeze.

• 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 county is busy the same fortnight and containers get scarce.
• Separate fencing and gutters from the roofing if the same storm took those down — metal has its own route and its own value.

Placement, canopy and the nail problem

Roofing containers need to sit close to the house, and around here there are three recurring constraints.

Grade. A roofing container needs to be close to the building, and on a sloped property the closest spot is not always the most workable one. Tell us the approach — it matters more here than most places.

Overhead branches. Twenty-two feet of clear height to raise the bed, and on a job with a mid-course swap that has to work twice.

Driveway width. In the older borough streets a 15 yard with a swap is often the workable shape where a 20 simply will not place.

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.