Hi Joe,

I really don't know how much water is involved in a hydroponic system, but its weight adds up quickly (8 lbs/gallon). Each roof will have to bear that weight as well as whatever weight of rain or snow it is designed for. Whatever framework you use to support your operation will have to be designed so that it has no pointy bits on the bottom that could puncture the roof membrane. You'll also need to think about how much weight is concentrated in one point, as opposed to the whole weight of the structure.

How will you get waste (root balls, etc) down from the roof? Many roof access points are a narrow, inconvenient stair, and you won't be welcome carrying drippy buckets through carpeted office space.

Katey

Thanks for the reply Katey! This of course has to be the perfect building and setup. Weight shouldn't be an issue because the system itself is pretty lightweight; the nutrients will run though PVC grow chambers and recycle back to a reservoir that will be down on the solid ground. There will be practically no medium (1- 1" cube per plant) to worry about. I haven't done the math on overall lbs. yet but I think one of the more considerable problems will be securing down the cover structure to the roof. As far as getting down waste, it's an issue, I would be growing Basil, cutting tops every 12 days so there would only be large amounts of roots on the days of replacing plants, which would be thrown into a dumpster. Thanks for your thoughts and questions!