Twenty-two calculators, one Revit plugin, and a methodology index. Everything cited back to NJAC, IBC, ACI, ASCE, NEC, NSPC, IFGC, and the local ordinances we actually work under. We built them for our own projects — and kept them free because someone else might need them too.
Export architectural BIM models to multi-color 3MF files for desktop 3D printing. Automatic 18-category material separation, glass and frame detection, section box clipping, model slicing, and thin geometry inflation. Slicer-ready for Bambu Lab and other FDM printers.
BIM-linked stormwater runoff analytics, dynamic Toposolid/Topography LAG elevation polling, concrete paved walkway limits segregation, and automatic sheet-ready NJAC schedule generation.
Free web code calculators and advanced BIM plugins built to speed up real-world construction. Grouped by design workflow — from site analysis to structural checks and MEP sizing.
Independent scaled curriculum, educational archives, and vocational workshops. We show our math and document the legacy of Black builders.
Explore Learning Suite →Floor area ratio and lot coverage. Dynamic floor list with exclude toggle for cellar, mechanical, parking. Pass/fail against zoning limits.
Off-street parking, loading, EVSE, micromobility, auto-share credit, and shared parking per Newark Ord. §41:7. All Table 7-1 through 7-5 uses.
Grade points with garage door tags. Derives lowest/highest adj. grade, first floor minimum, basement sill/floor elevations, and garage slab with slope.
NJAC 7:8 (Jan 2026) compliance + Newark §41:17 product sizing. Major and minor development, NOAA PFDS site-specific rainfall, water quality, BMP selection, volumetric reduction, elevation auto-adjust.
How the stormwater calculator works — rational method, NRCS runoff, water quality, BMP sizing, groundwater recharge methodology explained.
Quick-reference definitions for 33 stormwater terms and abbreviations. Alphabetical, with links to the full methodology.
Select materials and assembly ratings. Determines qualifying IBC construction types including Type IV mass timber subtypes.
Allowable height, stories, and area with frontage increase. Non-separated vs separated mixed occupancy side by side. Fire separations per Table 508.4.
Exterior wall fire-resistance rating, allowable opening area, opening protection, and projection limits by FSD, construction type, occupancy, and sprinkler status. Bearing wall cross-check with Table 602.
Multi-floor egress widths with automatic stair accumulation, exit count warnings, and stair discharge onto exit discharge level with 50% rule check.
Occupant load by floor and space per IBC Table 1004.5. All 40 functions of space with gross/net designation, fixed seating by count, and building total with Revit text output.
Scope-of-work classification for existing buildings. Repair, Renovation, Alteration, Reconstruction, Change of Use, Addition — with compliance triggers, Basic & Supplemental Requirements, hazard table.
Rectangular pad footing design. 10 ACI checks with pass/fail. Eccentricity, multi-layer rebar, auto-sizing with constraints. Presumptive or geotechnical bearing.
Dimensional lumber and engineered I-joist floor spans. Size by span across IRC tables and 6 manufacturers, or find equivalent substitutions between TJI, LP, BCI, Nordic, GP, and APA PRI.
Build up assembly dead loads layer by layer. Preset materials for common roof, floor, wall, and ceiling assemblies with custom entry.
Minimum fixture counts for mixed occupancies with 2/3 occupant load reduction and urinal substitution.
Size service line, cold/hot mains by NSPC Appendix B simplified method. Copper K/L/M, CPVC SDR11, PEX SDR9. Pressure budget, booster/PRV triggers, fixture supply branch table, residential water softener, SVG/PNG/DXF riser diagram export.
Sanitary drainage by floor — DFU counts, horizontal branches, stacks, building drain/sewer, vent stacks, branch vents, trap arms. Floor model with BWV flagging and WC restriction checks.
Dwelling unit and multifamily service sizing per NEC 220.82, 220.83, and 220.84. Appliance loads, HVAC, EV charging, demand factors, and Revit-ready text output.
Natural gas / Schedule 40 black iron / low pressure. Predesign quick lookup or full appliance list with per-segment sizing, SVG piping schematic, and Revit text output.
Drawing set completeness checklist for NJ UCC plan review. 135 items across 13 sections with Yes/No/N/A tracking. Scope-aware — sprinkler and elevator items toggle automatically.
Full project lifecycle checklist — Pre-Design through Post-Construction. 8 phases, 167 items with Done / In Progress / Not Started / N/A tracking. Optional NJ items toggle.
Every calculator has a methodology page explaining the equations, coefficients, and code assumptions. No black boxes. If you want to check our work, you can.
22 calculators · free forever
Code-cited · methodology-open
Got a calc you wish existed? Tell us in the intake form — info@greenstoriesllc.com.
We keep all 22 calculators free. In exchange we’d like to know who’s using them — so when we ship something new, you’ll hear about it first. One email, one time.