It's great when people invent their own ways of doing things. Nori has come up with her own approach to a greenwall system; no soil, carpet padding for felt, fishtank reservoir. I love it! Here's her system in her own words and a link to her blog with lots more info.
Matt, I have a vertical garden that isn't quite what you have described. Mine uses a single layer of nylon felt stapled to a backer board with the plantings using little to no dirt. Here's the first page of posts (lots of pics). Read through to the end for the complete tale.
I am using a single layer of nylon carpeting padding felt (well rinsed before use). The majority of the soil was removed from the planted starts. Anything I had started in water was tucked into a pocket sans soil. Seeds were pressed into pinches of peat moss in tiny pockets.
My wall is fed from a 30 gallon aquarium with two small goldies and a pleco. I started using a 3 gallon bucket with water from one of our outdoor fish tanks. I add a small amount of potash(? - going from memory here . . . ) monthly. I top up the aquarium monthly so combine these tasks. I feed the fish every morning and have the aquarium filter set at 85.
So far my wall is doing awesomely well. I planted it in April. The geranium and begonia have bloomed. I'm holding out hope for the vining black eyed susan and coleus but will probably have to wait for spring.
I am planning a larger plant wall to go on the north wall of our sun porch (glass roof so won't be using the shade loving house plants in this wall). I was able to get some LDPE sheets destined for recycle from a local printer. They're about 3/8" thick and about 3'x4'. I'll screw them to a framework, sealing the seams and staple on my felt.
I like this felt. It feels dry except when the pump is running water through it. It may be best to use 2 layers of felt, but so far the wall is awesome with a single sheet.
elf at elfnori dot com