You want to grow food on your roof – wonderful. Now how the heck do you get up there?
Rooftop access can be tricky from both an infrastructural and legal perspective. Here are some accumulated observations from my days overseeing green roof construction around the country.
1| Size matters: The roofs on which I’ve worked have ranged in size from 850 to 120,000 square feet (2.75 acres). Small roofs, such as those atop townhouses and small mixed-use buildings, are often accessed by mechanical lifts during construction, and with a head house, roof hatch, or temporary ladder after construction. Large roofs, by contrast, rely upon cranes during construction, and often contain elevators, stairwells, or hatches with secure ladders for permanent rooftop access. In general, large roofs are much more likely to contain the architectural infrastructure that is necessary to access the roof on a regular basis. Most small roofs do not contain adequate infrastructure, and the provision of such is often cost prohibitive.
2| Safety first: When growing food on a roof, structurally secure access is a must. You will need to carry bulky elements such as tubs of compost, hoses, and baskets of vegetables up and down from the roof, and a ladder can be very dangerous for these activities. In order to promote safety, many building codes actually require that certain architectural infrastructure be in place for regular rooftop access. No matter how badly you want to farm your roof, nothing will ruin your weekend like a serious injury; be careful up there!
3| Informing design: Planning for regular roof access during the design of the building can ensure safe and easy vertical circulation. If the roof is intended to be farmed, then consideration should be paid to how and where the roof will be accessed. The rooftop activities may inform what type of access is most suitable, or by contrast, the type of access may inform rooftop activity. Incorporating rooftop access as an afterthought can be extremely expensive, and so it is best to plan ahead for such activities.