As your asparagus lies low waiting for spring, it has plenty of time to fantasize about warmer soil. Jump up to a rooftop, and this fantasy could be closer to reality than your vegetables have ever dreamed.
Buildings emit heat. Since hot air rises, local building codes specify how much insulation must be installed inside the roof to keep this heat from escaping. But what if there were a way to let some of this heat enter a rooftop greenhouse?
Some ground-level greenhouses rely upon radiant heating to regulate winter temperatures. This method involves heating the floor so that hot air can warm the plants and soil. Perhaps this same principle can be applied to rooftop greenhouses, whereby heat from the building is harnessed and re-used. With new construction, could municipalities be convinced to allow for thinner insulation below greenhouses?
In my travels, I have yet to see this practice in action. Do you think that it’s feasible? Would municipalities allow for such an unusual variance?