Flat rubber roof

I have experience with asphalt roofing, but not flat roofing. I have a relative whose flat roof is leaking. It has two levels. The lower level is rubber roof that has outlived its expectancy. How is the best way to install a new roof on this section? Over the top of the old one? Suggestions on specific brands or materials to use???

The other area is the older pebble mixture on a flat roof. Suggestions for leaky areas on that roof?


tear them off?

Yep, tear them off.