ShingleTally is an independent site that works out roofing quantities — squares, bundles, starter, cap, underlayment and nails.
It exists because roofing quantities are simple arithmetic hidden behind two conversions — footprint to roof area, roof area to squares — and almost nobody publishes both in one place with the pitch factor spelled out.
Where the numbers come from
- the pitch factor √(1 + (rise/12)²), which is geometry rather than an estimate
- IRC R905 for underlayment and ice barrier requirements
- standard bundle coverage of three bundles per square for architectural shingle
Every page states the source and the assumptions behind its figures, because a number without its assumptions is not much use. Where a number is a roofing convention rather than a measurement — the standard three bundles to a square — the page says so plainly.
Pitch turns 1,200 ft² into 1,442
Footprint is not roof area. A 40 × 30 ft house covers 1,200 ft² of ground but 1,442 ft² of roof at an 8/12 pitch — two and a half squares nobody ordered, before waste is counted.
What this site does not do
We do not advise on structural repairs to a roof deck or on whether a roof can take a second layer. Both need someone on the roof looking at it.
Who runs it
One roofer-adjacent person, doing this between other work. No editorial team, and inventing one would be worse than admitting there is not. The check on this site is that every figure names its pitch factor, its bundle count or its manufacturer sheet.
Every calculation is code, run against every pitch and span combination the site offers, so an error in a constant shows up across the whole set instead of hiding on one page. When something is wrong here it gets corrected, with a note saying what changed.
How it is paid for
ShingleTally is free to read and funded by display advertising. No sponsorships, no affiliate links. A page that tells you three bundles is telling you three bundles because that is the number.
Getting in touch
Corrections and questions go to [email protected]. Corrections are the single most useful thing to send — the editorial policy explains how they are handled.