The cheapest time to change a building is before it's drawn in detail. Moving a wall, simplifying the roof, or switching the structural system costs almost nothing during schematic design, and a great deal after construction documents are finished.
A preliminary estimate puts a cost on the design while those choices are still open. We price concept sketches, schematic plans, and early design development drawings so owners and design teams can see what the design costs now, what's driving it, and where the alternatives sit.
If you need a full bid-ready number, you'll want a detailed estimate from construction documents instead. Building estimating →
A preliminary estimate uses the information that exists and doesn't pretend to more precision than the drawings allow.
What exists: building use, approximate size, number of floors, site. How we price it: cost per square foot or per unit (per bed, per apartment, per parking space), adjusted for location, quality level, and building type, then split into major systems. This is a rough order of magnitude (ROM) estimate.
What exists: floor plans, basic elevations, an outline of the structural and MEP approach. How we price it: assemblies (priced square feet of each wall type, roof type, floor system, and MEP system) measured from the plans. Interior finishes and details are carried as allowances.
What exists: most systems are defined; details and specs are in progress. How we price it: quantity takeoffs for most major elements, with allowances only for the parts that aren't drawn yet.
Accuracy follows design maturity. AACE International's estimate classification system is a common way to describe this: a Class 5 estimate is based on very limited project definition and carries a wide range; a Class 3 estimate, built on substantially developed design, is much tighter. Most preliminary estimates fall between Class 5 and Class 3.
What matters for you is that the estimate states its range and its assumptions. A preliminary estimate that presents a single precise-looking number without either is less useful than it appears.
A square-foot cost from a database treats every building of the same type as identical. They aren't. These design decisions move the cost long before details are drawn, and a good preliminary estimate accounts for them:
A long, narrow building or one with many corners has more exterior wall per square foot of floor than a compact square one. Exterior wall is one of the most expensive systems in a building.
Extra height adds wall area, column length, stair runs, and duct and pipe risers on every floor.
Longer spans need deeper members. Wood, steel, concrete, and masonry each carry different costs and schedules in different markets.
Moving from low-rise to mid-rise can trigger code changes: different construction types, sprinklers, elevators, and fire-rated assemblies.
Sloped sites, poor soils, and high water tables change the foundation system and earthwork.
A laboratory, kitchen, or medical space carries far more mechanical and electrical cost per square foot than an office or warehouse.
More glass usually means more cost, and can increase mechanical loads.
When we see these factors in your drawings, we price them directly instead of averaging them away.
Much of a preliminary estimate's value comes from comparison. We can price alternatives side by side, for example:
Each option shows its cost difference and what else it affects (structure, schedule, or another trade) so the comparison is fair. Estimating consultant →
An allowance is a set amount carried for something that isn't designed yet: say, interior finishes, specialty equipment, or site lighting. Allowances aren't padding; they're placeholders. In our preliminary estimates each one is labeled, so as the design catches up, you know which numbers to replace with real takeoffs.
checking a design against the owner's target cost
deciding whether to move to the next design phase Budget estimating →
pricing proposals from early documents
testing a house design before paying for full drawings
Upload the drawings through our quote form, share a Google Drive or plan-room link, or email them. Large sets travel best as a shared folder.
Upload Your Plans →Or email info@primeestimation.com.
Send your drawings or project description
We confirm the scope, the method suited to your design stage, the fee, and the delivery date
We prepare the estimate, asking about anything the drawings leave open
When the design advances, we can update it.
It's a cost estimate prepared before construction documents are complete, used to guide design decisions and confirm the project is on budget. It's less precise than a detailed bid estimate but far more useful at the stage when design changes are cheap.
A conceptual or rough order of magnitude estimate is the earliest form of preliminary estimate, built from program information. Preliminary estimates also include schematic and design development estimates, which use more detailed drawings.
Yes, at a conceptual level. With the building's use, size, location, and quality level, we can prepare a ROM estimate. The range will be wide, and we'll say so.
A preliminary estimate prices the construction of an early design to help choose and refine it. A budget estimate sets the owner's full project budget, including soft costs and contingency, for funding and approval.
Bids depend on the final design and market conditions at bid time. The best way to keep them close is to update the estimate at each design stage.
Send your current drawings and the decisions you're facing. We'll recommend the right level of estimate and quote the fee.
