The roof of your building may hold HVAC equipment and other items, but it also has a lot of open space. Many building owners have started transforming that extra space into areas where tenants can have small container gardens. Others have created recreational spaces where people can sit and enjoy the view, and these spaces often include greenery. If you’re considering turning your plain rooftop into a garden that your tenants can use all year round, you’ll need to consider several issues.
How Will You Maintain the Roof?
The roof itself will also need periodic maintenance. If you’re installing decks or lots of walkways around the roof, how are you going to be able to access the roof itself? If the roof needs replacement, how will your garden design allow for that work? It can be done, obviously, but you’ll want help from rooftop landscaping designers so that your rooftop garden doesn’t create complications.
Find Out the Maximum Weight the Roof and Building Can Hold
First, always find out how much weight the roof and building can handle. The added load of a garden places more strain on the structure of the building as a whole, so you’re not just looking at the flat expanse of the roof and whether the roof membrane will stay intact. Keep in mind the weight of wet soil, snow, and any fruit if you’re letting tenants have small fruit trees in containers. You need to factor in the plant’s mature height and weight along with anything else on the patio in proportion to how much the building’s roof can hold.
Evaluate Drainage
You’ll need to decide how you want to deal with drainage from the soil and any containers. Drip irrigation may be OK for a container (assuming the irrigation line isn’t pulled out of the soil and left on the roof). But if you create “in-ground” plantings, a sprinkler system may be safer to use. You’ll have to keep a close eye on the irrigation and drainage to ensure the roof itself stays in good shape and doesn’t begin leaking on tenants below.
Who Will Maintain the Garden?
If you’re creating space for tenants to have a few containers, then the tenants may take care of garden maintenance most of the time. But if you’re adding “in-ground”-style greenery, you’ll need to ensure that anyone maintaining that space has room below to park their vehicles. It sounds like the strangest thing to consider, but if you have a gardening or landscaping company coming over weekly to maintain the rooftop garden in a crowded city, they need to be able to access it without having to drag equipment from parking several blocks away.
Snow Load on Canopies
If the garden includes a place for tenants to sit and talk, a canopy can help keep the sun and snow off the people. However, the weight of the snow can damage the canopy if you’re not careful when you design the seating area. You also need to ensure the canopy won’t be blown away in the wind. Strategically placed openings to let wind through and a proper slope to let snow slide off can help with both issues. But again, consulting with rooftop garden design companies is best. Professional designers can help you choose the best fittings for the climate you’re in.