Convert zoning inputs into reliable yield estimates. Model mix, density, and parking with clear assumptions. Make better planning decisions on every residential project today.
| Scenario | Site Area (sqm) | Net Dev (%) | FAR | Efficiency (%) | Net Res Area (sqm) | Estimated Units |
|---|---|---|---|---|---|---|
| Urban infill | 10,000 | 85 | 2.2 | 78 | 12,944 | ~160 |
| Transit corridor | 18,000 | 90 | 3.5 | 80 | 40,320 | ~420 |
| Suburban edge | 25,000 | 80 | 1.6 | 75 | 21,600 | ~240 |
The calculator applies a planning-level yield model. It starts from site area, applies a net developable factor, then uses FAR to estimate gross buildable floor area.
Efficiency and common area assumptions vary by building form, corridor type, and amenity strategy. Use local benchmarks or recent projects for best results.
Begin with gross parcel area, then apply a net developable factor to remove dedications, easements, flood buffers, and irregular corners. On many urban sites, net developable land ranges from 75% to 95%. Using a realistic range early prevents overestimating floor area and reduces redesign later.
Floor area ratio converts land into gross buildable floor area. For example, 10,000 sqm at 85% net developable with FAR 2.2 yields about 18,700 sqm of GFA. Pair FAR with lot coverage to sense check form; if coverage is 45%, the implied stories are roughly GFA divided by footprint, highlighting when a mid-rise assumption becomes a tower condition.
Mixed-use schemes rarely dedicate 100% of GFA to housing. Apply a residential share, then use an efficiency factor to approximate net sellable or net rentable area. Typical planning efficiencies fall between 70% and 85% depending on corridor type, core size, and structural grid. A separate common area allowance helps model amenity-heavy projects.
Unit yield is net residential area divided by unit size. Using a mix improves accuracy: studios at 42 sqm, one-bedrooms at 68 sqm, and two-bedrooms at 92 sqm will produce a different count than a single average size. Normalize mix shares to 100% and choose conservative rounding when reporting headline yield.
Parking ratio and reductions materially affect feasibility. At 1.1 stalls per unit with a 15% reduction, 200 units require about 187 stalls. Open space requirements reduce usable land and can constrain footprint. Review density in units per acre or hectare to compare against local benchmarks, then export CSV or PDF to document assumptions for stakeholders and lenders very quickly.
It is the portion of the site you can practically develop after deducting constraints like easements, rights-of-way, flood buffers, steep slopes, and required dedications.
Floor is conservative and common in early feasibility. Round can be used for mid-stage comparisons. Ceil is optimistic and should be justified with a design that confirms the extra units.
Use benchmarks from similar local projects. Efficiency depends on corridor type, core size, structural spans, and amenity layout. Early estimates often fall between 70% and 85%.
If your mix shares do not total 100%, the tool scales them proportionally to keep the breakdown consistent. This avoids under- or over-allocating net area across unit types.
No. Setbacks, height limits, daylight planes, structural grids, fire stairs, and circulation can reduce realizable area. Use this as a planning estimate, then validate with massing.
Parking stalls equal total rounded units multiplied by stalls per unit. A reduction factor can reflect transit proximity, shared parking, or transportation demand management measures.
No. It provides rapid scenario testing and transparent assumptions. Use it to screen opportunities and guide concept direction, then commission detailed code and design verification.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.