400 ft above structures doesn't override controlled airspace

[Xitor]

Just wanted to confirm my understanding that:

1. Recreational pilots are capped at 400 ft AGL
2. Part 107 pilots can add 400 feet above and around a structure for a max of 800 feet.
3. Controlled airspace is absolute AGL, and overrides height above buildings.
4. Same with class E airspace, if you're in a 700' class E, then that over rides 400 feet above structures too

So if you are in FAA 400 ft controlled air space flying over a 300 ft building, you can are still capped at the controlled airspace 400 ft, NOT 700 feet (300 ft building +400 feet). The only way to get above the controlled airspace limit it an approved FAA waiver, not simply flying over a tall building.

Ok, where have I gone wrong?

 

[MS Coast]

Just wanted to confirm my understanding that:

1. Recreational pilots are capped at 400 ft AGL
2. Part 107 pilots can add 400 feet above and around a structure for a max of 800 feet.
3. Controlled airspace is absolute AGL, and overrides height above buildings.
4. Same with class E airspace, if you're in a 700' class E, then that over rides 400 feet above structures too

So if you are in FAA 400 ft controlled air space flying over a 300 ft building, you can are still capped at the controlled airspace 400 ft, NOT 700 feet (300 ft building +400 feet). The only way to get above the controlled airspace limit it an approved FAA waiver, not simply flying over a tall building.

Ok, where have I gone wrong?

Looks right to me, with one exception in item 2. There's no absolute altitude cap, just 400' above the top of the structure. So, you could climb to 1400' AGL over a 1000' AGL structure.

On added requirement - Part 107 pilots flying above 400' AGL over structures are required to remain within 400 feet laterally of the structure.

Here's the ultimate source.

 

[Cafguy]

You are correct IF you are in CLASS G UNCONTROLLED Airspace...You may fly over the structure as you state BUT
.. Others (Class B, C, D, or...... E at the surface),You must have prior authorization from the FAA (usually via LAANC or DroneZone), and that authorization will specify a strict altitude ceiling (e.g., 100 ft, 200 ft, etc.) that generally overrides the structure rule.
Remember: .................CONTROLLED AIRSPACE limits OVERRIDE The 400 ft. above a structure rule.