People compare roof quotes on the total, because the total is the only number presented in the same units. It is also the least informative thing on the page. Almost every meaningful difference between two quotes sits in what each one includes, and those differences are legible once you know what the lines are for.
The unit everything is built on
Roofs are priced by the square, which is 100 square feet of roof surface rather than of floor. Pitch and shape mean the roof is always bigger than the footprint, so a house of a given size does not have a matching roof area.
Roof size is the multiplier behind every other number on a quote, which is why a quote that leaves out the square count hides the most checkable thing on it. Ask for the square count first, then compare two figures against each other.
What each line is actually for
The lines below appear on most quotes in some form. Here is what each one buys and what it costs you to go without.
- Tear-off: removing the old covering to bare deck. Skipping it means laying over, which hides the wood permanently.
- Decking: replacing wood found soft once the roof is open. Nobody can price this in advance, so a quote with a firm figure is guessing.
- Ice-and-water membrane: the rubbery layer at eaves and valleys where water backs up and sits. Cheap to include, expensive to omit.
- Underlayment: the second line across the whole deck. Grades differ and the difference is real.
- Flashing: new metal where the roof meets walls, chimneys and valleys. Reusing the old is the single most common quiet omission.
- Pipe boots: the seals around vent pipes. They go brittle, they are inexpensive, and they are where a young roof leaks.
- Ventilation: intake and exhaust, settled while the roof is open. Rarely quoted unless asked for.
- Disposal and clean-up: a dumpster, hauling and a magnet run for nails. Real cost, sometimes buried.
The three questions that separate two quotes
If you ask nothing else, ask these, and ask both companies the same three.
- Is the flashing new or reused? A cheaper quote very often means reused.
- What happens if decking has to be replaced, and at what rate per sheet?
- What is the square count you measured, and how did you arrive at it?
What a lower number usually means
Sometimes it means a leaner operation, and that is legitimate. More often it means one of the lines above is absent, and the absence surfaces in two or three years as a leak at a flashing nobody replaced.
The comparison worth making is not which total is lower but which list is complete. Once both quotes cover the same work, the price difference is finally telling you something about price.
Getting a scope you can hold a quote against
A written scope lists every one of those lines before anything starts, with photographs of what was found. Get in touch with Alma Roofing Co and a local roofer puts one together, free, and the cost page shows the ranges those lines usually land in.