Ground subsidence — land slowly sinking — can crack foundations, break pipes, and worsen flood risk. SibFly tells you, for any US address, how fast the ground has actually been moving (in millimeters per year), measured from NASA satellite radar, not modeled or estimated.
See a sample report · Coverage map · developers: API docs.
Satellite radar (InSAR) has measured how the ground at your address has moved, in millimeters per year, since 2016. SibFly reads that measurement for any US address: negative means the ground is sinking (subsidence), positive means it is rising (uplift). Enter an address and you get the measured rate with an uncertainty range.
As rough screening bands on the vertical rate: under about 3 mm/year is essentially stable; 3 to 8 mm/year is notable subsidence worth monitoring; more than 8 mm/year is rapid subsidence worth a closer look. Foundations are stressed by UNEVEN (differential) movement between points, not uniform sinking, so compare nearby readings.
It is measured, not modeled: NASA's OPERA project processes Copernicus Sentinel-1 radar into ground-motion at a 30-meter grid. SibFly reports the value for the exact cell your address falls in, with an uncertainty (1 sigma) and the date of the last observation. It is a screening estimate, not an engineering or survey-grade determination.
Checking whether your address is covered is free. A full measured report is a small flat fee. Addresses with no coverage or no reliable radar return are never charged.
A survey measures your lot at one moment; SibFly shows the multi-year trend of ground movement under the whole neighborhood from space. Use it to decide whether a professional geotechnical survey is worth commissioning.
SibFly is also an API: GET https://sibfly.com/api/v1/motion?address=... returns the measured mm/year (and in/year) with uncertainty, for $0.40 per covered report. Agents can self-register and there is a hosted MCP server. See the docs.
Screening estimate from satellite radar (NASA OPERA / Sentinel-1 InSAR). Not an engineering or survey-grade determination. © SIB Scientific.