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Methodology
Cost Data Sources and Estimating Methodology
Quick Answer
How Does Virginia Cost Estimating Build Its Estimates?
We measure quantities from your drawings with digital takeoff software, then price them using published construction cost databases, current Virginia supplier quotes, regional labor rates and recent bid results. Each estimate is labeled with an estimate class based on design maturity, documented with its assumptions, and reviewed by a second estimator before delivery.
Data Sources
Where Our Cost Data Comes From
Published Cost Databases
Nationally recognized construction cost data, adjusted to Virginia locations.
Supplier Quotes
Current pricing from Virginia and Mid-Atlantic suppliers for key and volatile materials.
Regional Labor Rates
Labor rates for each Virginia market, plus contractor-provided rates when supplied.
Wage Determinations
Applicable Virginia prevailing wage and federal Davis-Bacon determinations for public work.
Recent Bid Results
Feedback from recent Virginia bids and project outcomes.
Manufacturer Data
Equipment pricing and lead times for MEP and specialty systems.
Estimate Classes
How We Classify Estimate Accuracy
We follow the widely used AACE International estimate classification system (Recommended Practice 18R-97). The class depends on how complete the design is. Typical expected accuracy ranges are:
| Class | Design Maturity | Typical Use | Expected Accuracy Range |
|---|---|---|---|
| Class 5 | 0–2% | Concept screening | −20% to −50% / +30% to +100% |
| Class 4 | 1–15% | Feasibility study | −15% to −30% / +20% to +50% |
| Class 3 | 10–40% | Budget authorization | −10% to −20% / +10% to +30% |
| Class 2 | 30–75% | Control or bid/tender | −5% to −15% / +5% to +20% |
| Class 1 | 65–100% | Check estimate or bid | −3% to −10% / +3% to +15% |
Ranges vary with project complexity and conditions. Every report states its class and the assumptions behind it.
Our Method
Step-by-Step Methodology
- Document review: confirm the drawing set, revisions and addenda.
- Quantity takeoff: measure and count every item, with color-coded drawings.
- Unit pricing: apply material, labor and equipment costs for the project location.
- Productivity: adjust labor for site conditions, height, access and schedule.
- Markups: add general conditions, overhead, profit, bonds, insurance and contingency.
- Escalation: adjust for the expected construction start date when needed.
- Quality review: a second estimator checks quantities, pricing and scope.
See the client-facing version in Our Estimating Process.
Key Terms
Estimating Terms We Use
| Term | Meaning |
|---|---|
| Quantity takeoff | Measured quantities of materials and work items from the drawings |
| Unit cost | Cost per unit of measure for labor, material or equipment |
| Labor productivity | Hours needed per unit of work, adjusted for site conditions |
| General conditions | Project-level costs such as supervision, temporary facilities and cleanup |
| Contingency | An allowance for unknowns within the defined scope |
| Escalation | Adjustment for expected price changes before construction |
| Allowance | A stated amount for items not yet fully designed |
| Estimate class | Category describing design maturity and expected accuracy range |
Limitations
What Estimates Can and Cannot Do
An estimate is a professional opinion of probable cost based on the documents and market conditions at the time it is prepared. It is not a guarantee of bids or final cost. Design changes, unforeseen site conditions and market shifts can change actual costs. See our Disclaimer and Terms and Conditions.
Service Areas
Top Virginia Markets
Our Location
Visit Our Virginia Estimating Office
Virginia Cost Estimating
4041 University Dr, Fairfax, VA 22030, USA
Phone: 1 (571) 732 1030
Email: ask@virginiacostestimating.com
Our Fairfax office serves contractors, developers and homeowners across the Commonwealth, from Northern Virginia and Richmond to Hampton Roads, Charlottesville and the Shenandoah Valley. Plans are reviewed remotely, so location never slows down your estimate.