Uniformat II (ASTM E1557) organizes a building by functional elements (Substructure, Shell, Interiors, Services, Site), which is how designers and owners make decisions before drawings exist. MasterFormat (CSI/CSC) organizes work by trade result and is how subcontractors bid and how invoices are coded. Early feasibility is best modelled elementally, then cross-walked to MasterFormat divisions for procurement, so the engine allocates costs in Uniformat II and exports a MasterFormat CSV.

Raising clear height increases column length, unbraced lengths and lateral demand, so members get heavier; a move from 32 ft to 40 ft clear typically adds 10 to 18 percent to the superstructure element. Facade area grows almost linearly with height, so every extra foot of clear height adds perimeter times one foot of cladding, insulation and air barrier. The engine scales the B10 element by a power of the height ratio and recalculates facade area from perimeter and total height.

When groundwater sits within six feet of the slab, excavations need continuous dewatering (well points or deep wells), watertight shoring such as secant piles or sheet piles, and blindside waterproofing or bentonite tanking under slabs and against walls. The engine applies a substructure premium of roughly 35 percent plus a dewatering allowance per square foot of footprint, and extends duration, because pumping, monitoring and discharge permits stay on the critical path.

The engine draws monthly costs along a Beta cumulative distribution, funds draws with equity until the equity requirement is met, then advances debt up to the loan-to-cost limit. Each month it charges interest on the outstanding balance at APR divided by twelve and capitalizes it into the balance. Total interest carry is the sum of these monthly charges; because most spending lands in the middle of the schedule, the outstanding balance peaks near completion, so longer durations raise carry faster than cost alone.

A cold dark shell delivers structure, envelope, roof and site with utilities stubbed to the building but no HVAC distribution, lighting, ceilings or finished floors. A warm vanilla box adds base HVAC, lighting, restrooms, fire protection distribution and primed drywall, ready for a tenant to finish. Turnkey completes all interiors to an agreed standard. In elemental terms, shell mostly reduces Interiors and Services, which is why the engine scales the C and D elements separately.

Cross-laminated timber structures typically price 5 to 15 percent above steel or concrete on the frame element, partly offset by faster erection, lighter foundations and exposed finishes that replace ceilings. Embodied carbon in the structure can fall by half or more, and biogenic storage in the wood can be credited depending on the accounting standard. Constraints include building height limits under the code, fire engineering, moisture management and supplier lead times.

Early Suppression Fast Response sprinklers are designed to suppress high-pile storage fires from the ceiling without in-rack sprinklers, which matters for warehouses storing above 12 feet or with rack storage of plastics and mixed commodities. They need larger heads, higher pressures, often a fire pump and a stronger water supply, so the fire protection element usually costs 15 to 25 percent more than a wet pipe system, but they avoid in-rack piping that constrains racking changes.

A City Cost Index compares the cost of a fixed basket of construction labour, materials and equipment in a metro area with a national average of 100. Material indices move within a fairly narrow band because commodities trade regionally, while labour indices can range from roughly 55 to 175 because wage rates, union density, prevailing wage rules and productivity differ. The engine applies material, labour and equipment indices separately to each Uniformat element based on its labour and material split.

Under AACE International Recommended Practice 18R-97, a Class 5 estimate is prepared at 0 to 2 percent design definition for screening and concept, with expected accuracy of roughly minus 20 to 50 percent low and plus 30 to 100 percent high. A Class 3 estimate reflects 10 to 40 percent definition and supports budget authorization, with accuracy near minus 10 to 20 percent and plus 10 to 30 percent. Class 3 mode exposes geometry, geotechnical, systems and financing inputs so the model can tighten its range.

P10, P50 and P90 are cost values that the model expects to be exceeded 90, 50 and 10 percent of the time. P50 is the balanced budget for planning; P10 represents an aggressive buyout that assumes favourable market conditions; P90 is a conservative figure that includes most identified risk. Lenders and institutional owners usually size contingency and interest reserves between P80 and P90, while developers often underwrite returns at P50 and stress test at P90.

Ontario's Construction Act requires a 10 percent statutory holdback on each progress payment, released after the lien period expires, and sets prompt payment timelines of 28 days from a proper invoice to the contractor, then 7 days downstream to subcontractors and a further 7 days to sub-subcontractors. The engine models retainage as a monthly deduction from hard cost draws that is released after substantial performance, which shifts a meaningful block of cash to the end of the schedule.

Costs escalate from today to the midpoint of construction, so delaying the start pushes the whole cost base forward through additional months of inflation. The engine compounds the annual construction inflation rate over the delay plus half the construction duration and applies it to contract and soft costs before contingency. A 12-month delay at 4 percent inflation adds about 4 percent to the estimate, and interest carry then grows further because the larger base is drawn along the S-curve.

The engine applies benchmark emission intensities per square foot to each element: superstructure by framing system, substructure by foundation intensity, envelope by cladding and glazing area, interiors by fit-out scope, and building services by electrical density and standby generation. Concrete mixes with 30 or 50 percent slag replacement reduce cement-related emissions, and mass timber can carry a biogenic storage credit. Results are indicative upfront (A1 to A5) carbon, not a full whole-life assessment.

Development charges, impact fees and permit costs are modelled as a percentage of contract value that changes with the selected city; in the GTA they are among the highest in North America. Sales tax and HST are calculated on the material share of the contract and shown separately. Where a tax is recoverable by registered businesses, such as HST in Ontario, the default excludes it from total development cost, but a toggle lets you include it for non-registrant owners.