The formula
Every estimate is a sum of line items. Each line item is computed as:
The project total is the sum of enabled line items. Hiring a general contractor typically adds a further 20–25% GC markup, which we show separately rather than hiding it in the numbers.
Labor: BLS wages, resolved per metro
Labor is the reason renovation costs vary so much by geography, so we never use national labor averages when a local rate exists. Each labor line item carries a Standard Occupational Classification (SOC) code — carpenters are 47-2031, electricians 47-2111, plumbers 47-2152, and so on. Your ZIP code maps to a Core-Based Statistical Area (CBSA), and we look up the median hourly wage for that trade in that metro from the Bureau of Labor Statistics Occupational Employment and Wage Statistics program.
The fallback chain when a metro lacks data for a trade:
- Exact metro (CBSA) median wage
- Nearest metro with data for that trade (geographic distance)
- National median for the trade
Overhead: the honest multiplier
Raw wages are not what you pay. A contractor's billed rate carries insurance, payroll taxes, benefits, tools, vehicle, overhead, and profit. We apply an overhead factor of 1.3–1.5× to labor depending on quality tier — that's why our figures track real quotes rather than fantasy DIY math.
Materials: three quality tiers
Each line item has a baseline material cost and tier multipliers. Budget means stock and builder-grade, Standard means mid-grade (the most common choice), Premium means high-end materials and expanded scope. Tier also scales labor hours where finish quality genuinely takes longer.
What our numbers are — and aren't
These are educational planning figures, not quotes. They assume typical scope for each project type and typical site conditions. Structural surprises, layout changes, and unusual materials move real bids. Use our figures to sanity-check quotes and set budgets — then get itemized bids from licensed local contractors.
Data vintage & updates
Current wage data: BLS OEWS · May 2025 (BLS OEWS publishes annually each spring). Material baselines are reviewed with each data refresh. Every cost page carries an "updated" stamp reflecting its last build.
The same engine everywhere
The calculation engine on this site is the same logic the Renovio iOS app uses — the app adds per-project customization: your exact quantities, material selections, floor-plan-derived measurements, and GC markup.