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Creating a Commercial Rooftop Garden


Many commercial buildings struggle to make space for a landscaped garden where people can sit, relax, and have their lunch amongst living plants. We all know the benefits of having live plants in the workplace, but many businesses simply don’t have the room for a break out area that’s outdoors. In these instances, a rooftop garden is an ideal option that isn’t considered nearly as often as it should be.

These days we’re seeing more and more businesses located in the heart of a city transforming their rooftops into small gardens and ‘green’ spaces, allowing their employees to have somewhere to unwind and enjoy their lunch in the sun without having to even leave the building! Being able to enjoy some time amongst nature has a huge array of benefits, and can even help to boost productivity.

Structural considerations and approval

Before you head off to buy plants and supplies, here are a few important considerations to keep in mind.

  • You need to ensure that you have easy access to the rooftop, and it needs to be approved for pedestrian traffic,
  • The waterproof membrane needs to be completely intact and protected from your garden. Having this assessed by a professional is your best option,
  • Consider the elements and how windy and hot it can become on a rooftop. You’ll need to be able to block out the elements at least a little to make the space usable,
  • Before beginning, ensure that you have a structural engineer confirm the load capacity of your rooftop. When looking at the structural capacity, you need to take into consideration things like the garden beds and water tanks. Some rooftops were not designed to carry the amount of weight needed for a rooftop garden, so enlisting the expertise of a professional to assess this should be one of the very first items on your checklist,
  • Remember that you can cause leaks if you pierce the rooftop membrane, so ensure that this is not pierced when the garden is being placed,
  • All rooftop gardens need secure railings around the edge. Make sure you do not place anything too close to a railing as this could pose a potential hazard. Find out from your local council what the regulations are in terms of the height a railing needs to be if you will be installing this yourself,
  • Don’t forget to think about how you’re going to water your rooftop garden,
  • Council approval should be investigated at the beginning so as to make sure your plan is feasible. Find out what you need to do in terms of getting the approval for your rooftop garden,
  • Public safety issues are always a concern when it comes to public spaces, but your council should be able to inform you of everything you need to know, so ask lots of questions about the requirements for a rooftop garden.

Cosmetic considerations

  • The type of plants you use is really important. You don’t want water to pool on your rooftop, so you really want to go for plants that require minimal watering. Succulents are a great option for rooftop gardens as they’re low maintenance, don’t need much watering, and enjoy lots of sun,
  • Do you want all or part of your garden to be edible? Growing veggies and herbs can be a welcoming addition to any rooftop garden area, and something you should consider. How much more exciting would work lunches be?
  • Think about how you can anchor your shade. Perhaps a motorised or cantilevered umbrella is an ideal solution, or perhaps a few shade sails? This will all depend on the level of wind and how the sun hits your rooftop. Each space will have its own individual requirements,
  • Your outdoor seating and tables need to be able to weather the elements and remain secured to your rooftop,
  • Added elements such as a giant chessboard or ping pong table can add some more fun to your rooftop garden. If you have the space you may even want to consider a barbecue!

What if the rooftop has a limited weight capacity?

If your rooftop is unable to withstand a complete garden, consider container gardens that don’t weigh much. Remember when considering weight to always think of how heavy your soil will be at its wettest.

If your rooftop doesn’t meet the initial requirements for a rooftop garden, for example if there are issues with the waterproofing, this can be easily remedied by having a professional come out and fix or change the waterproofing membrane so that it’s suitable for your rooftop garden.

Rooftop gardens are ideal for commercial buildings for so many reasons. Not only do they provide an excellent break out area for those who inhabit the building space, but they actually help to insulate a building and even control stormwater runoff. Rooftop gardens can also actually prolong the life of your roof’s waterproof membrane. Amidst a concrete jungle, a rooftop garden is the perfect way to add some greenery to your environment, even if it’s in the heart of the city. For a more complete understanding check out our guide on creating a beautiful rooftop garden.

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