Sources
We list every data source used in our cost guides and when we last updated it. Each cost guide also lists the specific sources for that page.
| Source | What we use it for | Data |
|---|---|---|
| U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics (OEWS) | Hourly wages by trade, state and metro area | May 2025 release |
| U.S. Bureau of Labor Statistics, Producer Price Index (WPUIP2311101) and construction earnings (CES2000000003) | Adjusting older quotes and material prices to current levels | October 2026 |
| U.S. Bureau of Economic Analysis, Regional Price Parities | Location adjustment for materials and other costs | 2024 data |
| Retailer, manufacturer and supply house product pages (Lowe's, Menards, SupplyHouse and others) | Material and equipment prices (624 products) | October 2026 |
| Manufacturer installation guides and trade references | Labor hours per task | October 2026 |
| Statistics Canada / ISED industry financial benchmarks, NAHB cost of doing business study, public company filings | Contractor overhead and profit | 2024-2026 data |
| City permit fee schedules and open permit data (Chicago, Boston and others) | Permit fees and local job values | October 2026 |
| Publicly shared homeowner quotes and invoices (forums and communities) | Checking the model against real prices (1,400+ verified) | 2019-2026, indexed to 2026 |
| U.S. Census Bureau, American Community Survey (1-year) | Housing age, ownership and home values on city pages | 2024 data |
| NOAA National Centers for Environmental Information, Storm Events Database | Hail, wind, tornado and tropical storm history on city pages | 2016-2025 |
| Pacific Northwest National Laboratory, IECC 2021 climate zones by county | Climate zone on city pages | 2022 release |
| Texas Department of Insurance; Florida Statutes section 627.0629 | Insurance credits for impact- and wind-resistant roofs | Checked October 2026 |
How these sources become a cost range: How we calculate costs.
Material calculators
Our material calculators use standard geometry plus these product and reference data. Each calculator is tested against worked examples computed by a separate program.
| Source | What we use it for | Data |
|---|---|---|
| Quikrete Concrete Mix (No. 1101) data sheet | Concrete bag yields (40, 60 and 80 lb) | Checked October 2026 |
| Public ready-mix supply contracts (Des Moines, IA; Des Peres, MO; Allegany County, NY; Ottawa County, OK) | Ready-mix concrete price per cubic yard | 2025-2026 |
| Menards product listing | Price of a 60-lb bag of concrete mix | October 24, 2026 |
| Aggregate supplier density tables | Tons per cubic yard of gravel, stone and sand | 2026 |
| International Residential Code (2021), sections R105.2, R311.7, R312, R506 and R507 | Deck permit exemption, stairs, guards, slabs and deck framing | 2021 edition |
| Paint manufacturers' technical data sheets (Sherwin-Williams, Benjamin Moore, Behr) | Paint coverage per gallon by surface | Checked October 2026 |
| Custom Building Products technical data sheets (TDS-118, TDS-192, TDS-193) | Thinset coverage per bag by trowel size | Checked October 2026 |
| Penn State Extension, Purdue Extension (AY-28-W), University of California IPM | Topsoil depths for lawns, sod and garden beds | Checked October 2026 |
| Purdue Extension, Log and Tree Scaling Techniques (FNR-191) | Doyle, Scribner and International log rule formulas | Checked October 2026 |
| Leslie's, Calculating Pool Volume | Kidney-shaped pool volume approximation | Checked October 2026 |
| University of Illinois Extension, Proper Mulching Techniques | Recommended mulch depth | March 2024 |
| Home Innovation Research Labs, ANSI Z765-2021 | How appraisers measure house square footage | 2021 standard |