I live in a building which sits very high near the top of a hill. I estimate the ground level of the building to be around 700 feet, I live on the 13th floor, so my altitude is approximately 800 ~ 850 feet. I would like to get an accurate measurement (correct to +- 10 feet).
How I did the measure
- Measure the ground level altitude at a park with a phone GPS
- estimate the height of each floor
- I have a laser measurement tool which I can use to measure my ceiling height. But the height of each floor is ceiling height + some concrete. My tool cannot measure the distance from ground to my floor, it's too far away.
- Using a GPS unit in the flat would produce inaccurate results
- GPS units are inheritly inaccurate at altitude (compared to lateral position)
- I cannot access other floors other than the one I live
- I have a good view of the city. By looking at a map, I can accurately calculate my ground-level distance to certain sea-level landmarks. These landmarks are some 5 km away.
- I would like to minimize the cost of purchasing special equipment.