Enter a real address and your building's numbers to get the site facts, with the formulas behind every figure. Then take a short brief to your architect, or check a design you already have, and export it all for a licensed professional.
The results above cover physical site impact. A finished design also has to work through everything below — most of it needs a site visit, a survey, or your local planning office, not a calculator.
A drafting tool for an engineer to work faster in, not a substitute for one — every number here is still theirs to check and sign off. Start from a common layout below, or draw anything more specific by hand with the full tool set underneath.
Groundwork's calculators give you a real, formula-based first pass — but no software replaces a licensed architect, structural engineer or geotechnical engineer signing off on an actual build. This page compiles everything you've entered and calculated into one engineering brief, so a professional can pick up exactly where the tool leaves off instead of starting from scratch.
A worked example of what Groundwork would show for a real, famous building — using its actual published dimensions, run through the same five formulas as every other site here. It's a genuinely useful stress-test: at supertall scale, you can see exactly where the tool's simplified models hold up, and where they honestly don't.
Foundation bearing pressure: (3.5 kPa steel dead load + 2.5 kPa office live load) × 102 floors × 7,353 m² footprint = 4.50 million kN total load ÷ 7,353 m² = ≈612 kPa. Set the ground type to "Rock" (1,000 kPa) and the tool now specifically recognises rock-grade capacity and suggests "shallow spread footings bearing directly on exposed bedrock" rather than a generic deep foundation — which is exactly the real answer, and exactly why this building could stand here in 1931 without modern piling.
Shadow, right now: the tool uses real sun position for whatever latitude you enter. At New York's 40.75°N, a low afternoon sun around 20° elevation gives 381 ÷ tan(20°) ≈ 1,047m of shadow — reaching several blocks across Manhattan. That's exactly why towers at this scale need a formal, city-mandated daylight study, not a one-line estimate.
Stormwater runoff: the percentage increase versus natural ground doesn't actually depend on footprint size in this model — mostly-paved surface still comes back at roughly +350% versus the site's original ground cover, same as a small house on the same surface type.
Wind speedup — flagged, not hidden: set the manual "neighbour" comparison to a fairly typical nearby mid-rise (60m, 30m away) and the height ratio comes out at 6.35× — enough to push the formula past its ×2.6 ceiling. Rather than quietly reporting a meaningless number, the tool now marks the result "(capped)" and tells you outright: this ratio is outside the model's valid range, and real wind engineering here means a physical wind-tunnel or CFD study, not a bigger multiplier.
Sightline blocking — same treatment: against that same 60m neighbour, atan((381−60)÷30) comes out near vertical. Past 75° the tool now reports "90°+" instead of a falsely-precise decimal, and tells you a formal daylight/rights-to-light assessment is essential — not just "significant impact."
This also geocodes the real address and runs live OpenStreetMap research on it, exactly like any other address here — so the neighbours and wind/sightline numbers you'll see are genuinely detected around 350 Fifth Avenue, not scripted.
Already been to an architect or engineer and have a design in hand? This tab isn't for generating one — it checks the design you already have against the real site: does the specified foundation actually suit the load and ground, does the massing trigger wind or daylight problems your team should know about. Groundwork is for making a design work, not for making the design.
Everything Site Analysis flagged, in one place. Where your numbers give a clear answer, Groundwork resolves it automatically and shows the reasoning; where it genuinely can't — zoning, surveys, physical testing, legal agreements — it tells you plainly who to bring in instead.