Every estimate on fixpricer is rebuilt from its parts: materials, labor in your state, the contractor’s margin and fixed extras. Here is exactly how, in plain English.
The formula
Cost = (Q × material price + Q × hours × state wage) × (1 + margin) + extras| Input | What it means | Where it comes from |
|---|---|---|
| Q | How much work: linear feet, square feet or number of units | You enter it, with tips on how to measure |
| Material price | Cost per unit of the materials and equipment | Shelf prices from national home-improvement retailers |
| Hours | Labor time per unit of work | Calibrated on prices that installers publish themselves, and cross-checked against typical crew output |
| State wage | Hourly pay for the relevant trade in your state | U.S. Bureau of Labor Statistics |
| Margin | Contractor overhead and profit (insurance, vehicles, office, profit) | Stated on each guide with its source |
| Extras | Fixed costs such as removing old material, permits or a second story | Listed one by one on each guide |
Why you always get a range
Every input has a low, typical and high value, so every result is a range rather than one “magic number”:
- Low: lower-priced materials, the 25th-percentile wage for the trade in your state and a lean margin.
- Typical: mid-range materials, the median wage and a typical margin.
- High: premium materials, the 75th-percentile wage and a higher margin.
A quote inside the range isn’t automatically fair, and one outside it isn’t automatically a rip-off. Access, roof pitch, local permits and the condition of your home all move the price. The range is a starting point for a better conversation with your contractor.
Our sources
Material prices
We record shelf prices for standard products at national retailers such as Home Depot and Lowe’s, noting the product, the price and the date we checked it. Prices are re-checked every quarter. Each guide lists the products behind its numbers.
Labor
Wages come from the BLS Occupational Employment and Wage Statistics (OEWS) program, using state-level hourly wages for these occupations:
| Trade | SOC code | Used for |
|---|---|---|
| Roofers | 47-2181 | Gutters, gutter guards |
| Sheet metal workers | 47-2211 | Shown for comparison in gutter guides |
| Construction laborers | 47-2061 | Waterproofing, drains, crawl spaces |
| Plumbers, pipefitters and steamfitters | 47-2152 | Sump pumps |
| Electricians | 47-2111 | Electrical work |
BLS wages are what workers earn, not what a company bills. That’s why the margin is a separate, visible step instead of being hidden inside the labor rate.
Hours and margins
Labor hours per unit and contractor margins are the inputs with the least public data, so we treat them with the most care.
- Margin. We use the National Association of Home Builders’ Remodelers’ Cost of Doing Business Study, which reports the gross margin of remodeling companies (29.9% in 2024). We convert it to a markup on cost.
- Hours. We collect the prices that installers publish on their own websites, counting only companies that state their own rate. From each price we take out the margin, materials and fittings, and divide what’s left by the trade’s wage in that state. That gives the hours each company effectively bills per unit. We use the middle of that sample, and check it against typical crew output for the job.
Every guide names the installers and benchmarks behind its numbers. If we can’t find enough published data for an option, the calculator says so instead of guessing.
What our estimates don’t include
- Repairs to hidden damage found once work starts (rot, cracked foundations, old wiring).
- Local permit fees, unless the guide lists them as an extra.
- Sales tax, financing costs and emergency or after-hours rates.
How often we update
Material prices are checked quarterly and wage data is updated when BLS publishes a new edition. Every guide shows the date its data was last checked. If a number looks wrong to you, tell us and we’ll check it.
No data, no number: if we can’t find a reliable source for an input, the calculator doesn’t show a result for it.