Sea-level Elevations - Online Data 1

[DCEngr1]

Does anyone know of an online program that provides building elevations relative to sea level and/or building heights to local grade - preferably at no cost, and if possible, including the capability to locate heights of roof areas at different locations ?

 

[cvg]

google earth will show elevations
for more accuracy you will need to hire a surveyor
in the US, most surveys are not relative to sea level anymore, that was replaced in 1929 and again in 1988 with national datum's. Only a few local communities still use mean sea level and since the sea level is rising, that is a moving target.

National Geodetic Vertical Datum of 1929 (NGVD29)
North American Vertical Datum of 1988 (NAVD 88)

 

[SteelPE]

If you are looking to tie your building into the FIRM then you will need to use the NAVD 88 references. On projects I have worked on in the past, the information to calculate this and tie it into the building elevations was provided to us by the site engineer (jerk wouldn't do it himself).

 

[cvg]

not all firms are on navd88, you need to check the map or report carefully for the reference datum