On an older house (late 60s) had balcony re-surfaced on top of the garage (so it's important that it's waterproof). The contractor refinished it using a flat roofing roll material with little rocks on it that I've seen used for flat roofs, and the surround has tar goo to seal it... it seems kinda dumb to walk on rocky roofing material and drag all those crushed stones in the house.

Is that a true that they use those materials back then? I was told that the contractor re-installed the same as original on their balcony??