Roofing

Sizing a Dumpster for a Roof Tear-Off in Johnstown

Roofing is where sizing goes wrong most often, and around here there is a second problem: getting the container close enough to the house to be worth having.

The one number that matters: squares

Roofers measure in squares. One square is 100 square feet of roof surface. A typical Johnstown valley house runs somewhere between 16 and 24 squares; the larger Westmont and Richland properties can reach 30 to 40.

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

Run the arithmetic. A 24 square architectural shingle roof at 350 lb per square is roughly 8,400 pounds — over four tons before underlayment. That is comfortably inside a 20 yard but leaves little headroom if decking comes off too.

One local note on decking: older houses here are frequently sheathed with plank decking rather than plywood, and plank is heavier per square foot. If the roofer is re-sheathing, say so.

Shingle sizing table

Read that table alongside the placement section below, though. On a tight valley lot the honest answer is often a 15 yard with a planned swap even where the table says 20 — because the 20 will not fit.

Slate is a different calculation

Worth its own section because this region genuinely has slate, and getting it wrong is expensive.

Slate runs 800 to 1,500 pounds per square — three to five times asphalt shingle. A 25 square slate roof can be fifteen tons or more, which is well past what any single container can legally carry.

Slate therefore goes in a 10 yard, part-filled, with multiple swaps. Never a 30 yard: you would fill it a third of the way and it still could not be hauled. If you are taking slate off an older Westmont or Ebensburg house, tell us at the booking stage and we will plan the swap schedule rather than discovering it on the day.

The second layer problem

Plenty of older houses here have a second layer of shingle laid over the original. It roughly doubles the tear-off weight, and people often do not know until the crew is up there.

Look at the rake edge from the ground, where a double layer often shows as a noticeably thicker band, and ask your roofer to confirm during the inspection. If it turns out on the day, call us — a swap mid-job is far cheaper than an overloaded container that cannot be hauled.

Ice dams and what they hide

This is the mountain-climate roofing problem and it changes tear-off sizing more than anything else.

Ice dams form when heat escaping through the roof melts the underside of the snowpack, the water runs down and refreezes at the cold eave, and the resulting ridge backs water up under the shingles. Inside, it shows as a ceiling stain. Outside, it has usually been soaking the decking and the insulation for weeks.

The Laurel Highlands get real snow and hold it, so this is common rather than occasional. On any roof being replaced because of ice dam damage, budget for more decking than you think and for wet insulation coming out too. Both are much heavier than their dry equivalents. We size those jobs up on volume and down on the weight allowance, and we say so before you book.

Placement on a hillside lot

Roofing containers need to sit close to the house, and in this valley that is not always possible.

Three situations come up constantly:

• No driveway at all. Common in the older boroughs. The container goes on the street with a permit, or on a neighbour's arrangement, and that needs organising before the crew books.
• A steep driveway. A loaded container has to sit level enough to be hauled safely. On a sharp grade the workable placement may be at the street end, which means the crew carries further.
• Tree canopy. The truck needs roughly twenty-two feet of clear height to raise its bed. On the elm-lined Westmont streets that is the binding constraint, not the driveway.

Tell us the grade, the street width and the branches when you book. It is the difference between a delivery and a wasted trip. More on hillside access here.

The short mountain season

The practical roofing window here runs roughly from April to October, and at the Somerset end of our area it is shorter still because the plateau holds snow later and colder. Asphalt shingles need warmth to seal properly.

That compresses a year of roofing into about six or seven months, and spring is doubly busy because it is when winter's ice dam damage gets discovered and acted on.

If you are a roofing contractor, a standing arrangement with a local hauler is worth more here than in a twelve-month climate. We hold capacity for contractors who work with us regularly, and we are honest during the crunch about what we can and cannot deliver.

One last thing that is not about the container: a tear-off sheds an enormous quantity of nails. A magnet sweep of the driveway, pavement and street at the end of the job is twenty minutes well spent.