Possibly not what you are talking about but I have used ISOFLEX liquid rubber on a cracked concrete roof (an air raid shelter!), a couple of thick layers will last many years. Its not cheap but I didn't want to have to repeat the job and I found it relatively easy to work with.
Registered: 13th Feb 2010
I had my garage and carport (one flat roof) covered in sheet EDPM synthetic rubber.
I had already had it redone with bitumen and felt but this soon leaked and I was always fixing it. Felt/bitumen becomes brittle and cracks but rubber remains flexible as the roof expands and contracts.
The rubber sheet comes in one piece. They remove any sharp points and lay a polyester cushion material. The rubber sheet is laid on top and fed up adjoining walls by six inches and secured around the edges by grouting into the wall or with clips over the roof edge.
They fix and shape the sheet into the drain.
They then lay about four inches of gravel on top to weigh down the rubber sheet.
This worked fine for me for several years and was still fine when I sold the house.
The manufacturers gave a 25 year warranty against failure due to the elements. I was always careful to only go onto it in soft soled shoes to avoid punctures.
It has to be the right grade of synthetic rubber to withstand UV and heat from the sun.