Frequently Asked Questions
Collected from the feedback box and email. Most answers are one of two kinds — "that is what the data says" or "that is deliberate" — and each answer says which.
About the plates
A building that exists is not on the map.
Two cases. If the footprint is missing from the 2D plates too, it is not yet in Overture Maps (whose footprints compile OpenStreetMap, Microsoft and Esri sources) — most often a recent completion. If it is in 2D but not in 3D, none of its height sources (the city or county, our USGS LiDAR, Overture) has a height or a floor count for it, and we do not invent one. See the Data sources page.
Why is so much gray ("unknown")?
Buildings whose use or year built is not in the assessor data. Coverage differs by city and neighborhood; the Data sources page gives the measured share. Gray is deliberate — a plausible color would be a lie. A neighborhood with a lot of gray often simply has a lot of new construction.
Which areas does the US edition cover?
New York City (the five boroughs), the City of Los Angeles, San Francisco, Boston, Washington, DC, Chicago, Miami, Dallas, Houston, Denver, Seattle and Minneapolis, for now. Building age, building use and plot size come from each city's tax-lot data — MapPLUTO in New York, the County Assessor's parcels in Los Angeles, the secured property roll in San Francisco, MassGIS assessor parcels in Boston, Office of Tax and Revenue parcels in Washington, DC, Cook County Assessor parcels in Chicago, Miami-Dade Property Appraiser parcels in Miami, Dallas Central Appraisal District parcels in Dallas, Harris Central Appraisal District parcels in Houston (Houston has no zoning), City and County of Denver assessor parcels in Denver, King County Assessor parcels in Seattle, City of Minneapolis assessor parcels in Minneapolis — and the trees panel was checked against each city's street tree records (see Trees) — in Washington, DC it draws the District's own measured 2020 canopy instead, and in Chicago, Miami and Dallas it was checked against tract, county and city canopy maps. In Denver it was checked against the City's 2020 neighborhood canopy, with a stricter lawn filter (2.5 points off on average), in Seattle against the City's 2021 census-tract canopy, with its own lawn filter (2.7 points off on average), and in Minneapolis against the Metropolitan Council's 2021 canopy for its eleven communities (3.0 points off on average). Sites outside these twelve cities are not available yet — Santa Monica, Beverly Hills and other cities inside Los Angeles County have their own zoning and street data. Zoning shows in the parcel Details; district plans and planned facilities are Korean instruments, so they are not in the US set.
Can I use a larger radius?
Plates go to 1 mi; the wind simulation to about 0.6 mi (3,280 ft). Beyond that a building becomes a dot inside the frame, and simulation cost grows with the cube of the radius. For a larger area, move the center and make several plates.
Why a circle? Can I have a rectangle?
You can switch the frame to a circle, square, 4:3 or 16:9. The circle is the default because it is the convention for site-analysis boards and, having no orientation, says "the site and its surroundings" most plainly.
Can I change the colors?
Each panel has an accent color. The ramp keeps its lightness and saturation and only the hue changes, so bands stay legible. Background grays — the right-of-way gray on the plot-size panel, for instance — do not follow the accent. For full control, download the SVG (SVG workflow). Changing colors and SVG export are Pro features (see Plans).
About computation
The wind simulation says "failed", but it appears immediately if I try again.
Before September 1, 2026 that was our fault: the server finished, but a proxy in between dropped the connection at 100 seconds, so the browser saw a failure while the result landed in the cache. Start and status are now separate requests and the trap is gone. If you still see it, please tell us.
How long do wind, thermal comfort and sun hours take?
| 1,000 ft radius | ½ mi radius | |
|---|---|---|
| Wind simulation | ~30 s | ~3 min |
| Thermal comfort (with a wind result) | seconds | seconds to ~20 s |
| Sun hours | ~4 s | ~28 s |
| Diagram panels (each) | 0.2–2 s (sun-hours panel up to ~25 s) | |
The same site and settings come back instantly from cache. If several people compute at once you queue, and the sheet shows it. The first request in a US city outside New York can take two to three minutes while its base tile is built; if the screen gives up, reload — the tile will be ready.
The result for the same site changed since last time.
When we fix the logic the cache version increments and the site is recomputed. Thermal comfort changed when tree shade was added; sun hours changed when the shadow function was unified. Each guide records when and why.
About saving and files
The PNG has text on it. I only want the image.
Use the separate "plate only" button: title, color bar and caption are dropped; the site marker, compass and wind arrow stay. The default save keeps the caption on purpose — an unlabelled analysis image landing in a report is the failure this tool most wants to avoid. If you take the bare plate, caption it yourself.
Some views have no SVG.
The wind plan and 3D, the thermal-comfort and sun-hours maps are raster (pixel computations) and cannot be vectorized; the SVG button is disabled there and PNG is offered. The wind rose and all diagram panels export as SVG with Pro; PNG downloads are free.
The file will not open in SketchUp.
If you downloaded SKP, it opens by double-click or File ▸ Open, including in SketchUp Free. SKP files from before September 3, 2026 have flipped faces and render white — download again. The older DAE files do not open in Free at all and need File ▸ Import in Pro. Details in 3D export.
Files overwrite each other.
Filenames include the site, radius and settings (height for wind, color mode for 3D), so changing a setting produces a new name. If your browser renames downloads, check its download settings.
About use
Can I use this in a client report or a competition entry? Commercially?
Yes. The diagrams, SVG, DXF and 3D files can be used in reports, presentations, proposals and competition entries, including commercial work. Conditions are in the Terms.
Do I have to attribute?
Keep the source line under each plate (Overture Maps, OpenStreetMap contributors, the city or county building height data, USGS and so on). It is a condition of the underlying data — OSM-derived footprints carry the ODbL, whose share-alike clause applies if you redistribute a database, not an image — and it is what tells a reader the vintage and limits of what they are looking at. Crediting sitedia is not required.
Can I use this for a zoning determination or a shadow study?
No. Public data lags, elevation has errors, and buildings without heights are missing, so none of it is evidence for a regulatory finding. The sun-hours plate shows two reference criteria, but it measures the ground, not windows, and spots below missing buildings read brighter than reality. Use it for early layout decisions; do the determination with a survey and a validated tool.
Do I need an account? Is my site stored?
You can generate and view diagrams without an account. PNG downloads are free after sign-in; no Pro pass is needed. Pro features need an account — Google or email sign-in — and a Pro pass. When you sign in we keep your email (plus your name and profile image if you use Google) and a record of which features you use. The coordinates you query and the plates produced stay in a server cache so the next identical request is fast. Visit statistics use a cookie. See the Privacy policy.
Is there a Korean version?
Yes — sitedia started in Korea and the Korean edition covers the whole country with 28 panels, including zoning and cadastral layers that have no US equivalent. The data is entirely different, so it runs as a separate site.
The data is wrong. Where do I report it?
The feedback button at bottom right, or the email on the Contact page. Say which site (address or coordinates), which panel, and what differs. Errors in the source data are not ours to fix, but errors in our processing are — the "traps we hit" sections in the guides are that history.
What is free, and what does Pro cost?
The diagram set, PNG downloads (1000–4000 px, one at a time or as a ZIP) and the Credits line are free and will stay free. Pro adds editable SVG, color and background changes, the Details window (with Breakdown), Building mass with GLB, 3DM and SKP files, DXF, Section, Context map, and the Sun & shadow, Wind and Thermal comfort simulations. A Pro pass costs $9.99 for 3 months or $19.99 for 1 year, paid once with no automatic renewal. See Plans. Pass sales have not started yet; until they do, signing in gives you every feature at no cost.