If your building is in need of roof repair or replacement, this is the perfect time to reclaim that space and turn it into a rooftop garden. In fact, living roofs have gained popularity in many areas over the last several years. Especially if the building is in an urban area or your property is lacking in space for a proper garden, utilizing the roof is a great alternative. Not only could you grow flowers in a rooftop garden, but you can also use it for vegetables and herbs. Don't let your unfamiliarity with the idea discourage you. Here are a few things you'll need to consider to ensure that you get a safe, stable garden on your roof.
Make Sure Your Roof Is Structurally Sound
When you combine the weights of the containers, soil and plants, a rooftop garden can be heavier than you would think. In addition, watering those plants will contribute even more weight, so you need to account for that with your roofing contractor. He or she can offer some guidance about reinforcing your roof to ensure that it is strong. Reinforcements and additional cross-beams installed under the roofing will ensure that the building can support the weight of your new rooftop garden.
You're also going to need to make sure that the whole structure is protected against water damage. When you plant a rooftop garden, you'll need to be able to water it. Since that water will not only be retained in the planting medium, but will also drain off along the roof, you need a waterproofing barrier under the roofing material. Your roofing contractor can help you place a waterproofing layer at the base of the roofing material for extra protection.
Choose Your Containers Carefully
The planting containers you choose are more important than you might expect. Not only does the weight of the containers matter, but soil drainage is also a key consideration. Look for containers that are lightweight, such as plastic, PVC or wood. You can make your own containers in custom shapes or order prefabricated ones that will install directly on the roof. No matter which way you go, look for containers that have short side walls and flat bottoms. That way, you can be confident that the soil will be secure.
Choose containers that have sufficient drainage holes so that the roots don't drown. Finally, cover the entire bottom of each container with a weed barrier so that you eliminate the risk of any roots pushing through the container and penetrating the roof. This is only a concern if you're planting things with heavy root systems, but it's always best to be prepared.
Make Sure Your Soil Is Light
Soil is probably one of the heaviest components of a rooftop garden. That makes it one of the most important components to consider when you're building the structure. Look for a lightweight planting medium like loam, because potting soil is usually fairly heavy and will contribute unnecessary weight. It's just important to keep in mind that lightweight planting materials like this need to be replaced annually, because they won't hold nutrients for much longer than a single growing season, even if you work in extra fertilizer. Fresh loam treated with nutrient supplements will give your rooftop garden a great environment for growth each year.
Keep Yourself Safe
You'll have to be able to get up onto the roof and work periodically so that you can remove any weeds from the containers. If you're growing herbs and vegetables, you're going to want access to pick things from the plants. In either case, safety is paramount. Since living roofs can be installed on buildings with up to a 45-degree slope on the roof, it's essential that you're prepared. Create a safety barricade at the edge of your roof if it's sloped. This will catch anything that you might drop or that might slip down off the roof. It protects against something falling off the edge of the roof, which can be dangerous for anyone on the ground. In addition, consider adding some traction coating on the areas where you'll walk. That helps your feet stick, reducing your risk of slipping.
While you're at it, you should reduce the frequency with which you need to gain access to the roof. Since your rooftop garden will need to be watered regularly, talk with your roofing contractor about either adding an irrigation system to the roof that you can control from the ground or invest in a long watering wand that allows you to reach the plants from the ground.
Understanding the fundamentals of rooftop gardens will help you to create the perfect environment for growing your favorite plants on your building's roof. Whether you're adding color with flowers or creating sustainability with a vegetable garden, a local roofing contractor like Bell Roof Co can help you create the perfect foundation.