Flat Roof Question

The old adobe house I'm working on has a flat roof that has one of those stretchable membranes on it, with seams all over the place. The roof is supposed to be pitched slightly to allow the water to drain through a hole in the side and then down the downspout.

Problem is, the water doesn't drain properly, and there is a large pool that collects in the middle, which eventually seeps through and leaks into his living room. The owner wanted someone to jack up the roof to restore the correct pitch, but the contractor refused, because he thought it would cause structural damage. Now the owner wants me to put some kind of water sealant in the area that the water collects. I don't know of any roofing product that can adhere to this plastic membrane and withstand being covered in water for weeks at a time.

Is there such a product?

roof puddle...

A good chance there is already structual damage in this area.(dry/wet rotted roof joist).Have to see it but sounds like they may of installed "torch down" on the roof.
I would cut an inspection hole in the damaged drywall area to see what's going on above.post some pictures.
Trying to keep that water out is like putting a band aid on a shark bite...

Ponding on the roof violates all sorts of codes. A little puddle today can be a big puddle when it rains, and the weight of the water can bring the roof down.

We like to give DIY advice, and sometimes even "bandaid" advice. ( That is a controversial subject iteself). But, this sound like a problem that is beyond bandaid, and any attempt to "get by" will only lead to more grief for the homeowner and you. This one really needs to be fixed right.

Jimbo: There wouldn't be any grief for me, because I never warranty roof patching. I tell them that up front and even put it in writing.

Dog: No pics this time. It's a plastered ceiling. When it leaks, it leaks into the light fixture.

My gut feeling was that no product will hold up to "ponding". I guess I was right.

He'll have to bite the bullet and fix it right, but I know he won't.