Transparent methodology

How ProjectGauge builds roofing cost ranges

The model is designed to help homeowners understand a project before they hire—not to manufacture an exact bid from incomplete information.

Updated September 24, 2026Homeowner planning guide

What ProjectGauge is—and is not

ProjectGauge is a homeowner planning and quote-review tool. It is not a contractor bid, property inspection, engineering opinion, appraisal, insurance estimate or guarantee of market price.

How the roof cost model works

The current beta model uses published 2026 roofing-cost research as broad market anchors. For Southern California ZIP codes, ProjectGauge uses Los Angeles-area published material and replacement-cost data as the local launch-market reference. For other ZIP codes, it uses a national planning model.

The tool then adjusts the modeled band based on inputs including roof size, material, stories/access, complexity, tear-off and solar handling. It returns a range instead of one exact number because real bids vary with conditions the browser cannot inspect.

Current public sources

Why quotes can fall outside the model

Decking damage, structural work, code upgrades, specialty ventilation, roof-mounted equipment, access, unusual disposal conditions, premium product lines, extended warranties, contractor overhead and local permitting can all move a real quote outside the planning band.

Quote checking methodology

The quote checker does not label a contractor fair or unfair. It compares a submitted price with the same planning model and separately flags missing or unclear scope items. That separation matters: a quote can be within a modeled range and still have incomplete scope, or be outside the range for legitimate reasons.

How ProjectGauge will improve

As the product collects more legitimate usage data, the goal is to replace broad regional assumptions with more granular local calibration while keeping the model transparent. Any future partner routing or monetization is separate from the planning model and should not change the displayed estimate to favor a contractor.

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