Find out if your roof can carry a green roof — before you call anyone.
Enter your building's address or just its roof size, pick from hardy native plants, and Real Canopies will estimate the weight, the cost, and whether it's worth pursuing further.
The tool
Is this roof a candidate?
Fill in what you know on the left. Every number on the right updates automatically as you go. This is a screening tool, not an engineering report — treat it as a first, informed step.
Step 1
Your building and roof
Optional: look up a specific NYC address using public city records to pre-fill a rough roof size and get a general construction-era note.
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Step 2
Choose a system and your plants
The preset sets reasonable defaults for depth and drainage. Pick plants below — the weight and cost update to reflect exactly what you chose.
Advanced: adjust the construction assumptions the calculator uses
Estimated implementation cost
Weight per square foot
Total load on the roof
Feasibility signal
This tool combines published component weight ranges with public tax-record data. It is a screening estimate, not a structural calculation — final feasibility for any building must be verified by a New York State–licensed structural engineer reviewing the building's actual drawings, live load allowances, and the NYC Building Code.
Why it matters
The city's roofs are doing nothing for it
New York is roughly a third rooftop by surface area — almost all of it dark, impermeable, and structurally idle.
Heat
Dark roofs absorb sun all day and re-radiate it long after sunset. A vegetated roof stays dramatically cooler and insulates the building beneath it, cutting summer cooling costs.
Stormwater
New York largely runs on a combined sewer system. Heavy rain sends untreated runoff into the rivers — a green roof holds back a meaningful share of it before that happens.
Policy & habitat
Local Laws 92/94 already require green roofs or solar on most new construction, with a tax abatement to help offset cost. They also give pollinators, birds, and residents rare usable green space.
Plant library
Herbaceous perennials that come back on their own
Every plant here is a Northeast native or regionally adapted herbaceous perennial — no annual replanting. Green roof substrate is shallow, fast-draining, and exposed to full sun and wind, so these are matched to that environment rather than a garden bed.
Get approved
What to do next with the city
The general path for a voluntary retrofit in New York City. Scope and required filings vary by project, building, and whether Local Laws 92/94 already apply — treat this as an orientation, not a substitute for your architect, engineer, or the Department of Buildings' own guidance.
Check whether it's already required
If you're doing new construction or replacing an entire roof deck, Local Laws 92/94 likely already require a green roof, solar array, or both. Check the DOB's Local Law 92/94 page to see if your project is covered — that changes the process from "optional" to "compliance."
Hire a NYS-registered design professional
A licensed architect or structural engineer needs to verify actual load capacity from the building's drawings and prepare the design — this is required for any DOB filing, and it's the step that turns this tool's estimate into a real determination.
Check landmark status
If the building is individually landmarked or in a historic district, the Landmarks Preservation Commission needs to sign off before the Department of Buildings will issue a permit.
File with the Department of Buildings
Your design professional typically files the work through DOB NOW: Build as an alteration application, with drawings stamped by the engineer or architect of record.
Confirm stormwater requirements
Larger projects, or those in combined-sewer areas, may need a stormwater construction permit from the Department of Environmental Protection in addition to the DOB permit.
Build, inspect, and get sign-off
After the permit is issued, construction proceeds under the design professional's supervision, with DOB inspections leading to a final sign-off.
Apply for the tax abatement
Once complete, apply to the Department of Finance for the green roof property tax abatement, generally within a set window after installation, with your design professional's certification that the system meets program requirements.
For reference
Where the green roofs are (so far)
A small, well-documented sample — Real Canopies' full inventory would connect to NYC's Building Footprints and the TNC/Columbia CIESIN green roof survey.
Sample data only — six documented green roofs, locations approximate.