A roof garden offers many benefits, especially in a crowded urban environment. Being able to go to the roof of your building and be in the open air with plants and foliage provides a refreshing change from the glass, concrete, and steel below. Tending to the garden is a calming and relaxing activity that helps reduce mental stress. All gardens, including those on a roof, are environmentally friendly and help to clean the air and reduce pollution. For the building itself, a roof garden can, because of the excellent insulation it offers, help to reduce heating and cooling bills, protect the roof from ultra-violet rays and frost damage and reduce fire risks. But for all the benefits of roof gardens, there is a downside that must be considered before a decision to install one is taken.
For all the benefits of roof gardens, there is a downside that must be considered before a decision to install one is taken.
1.Types of Roof Gardens
There are 3 main types of roof gardens, which are also known as green roofs. The first is called the Extensive Green Roof and is the most basic type. This uses a shallow layer of inexpensive ordinary soil and supports drought resistant and low growth plants like herbs, mosses grass, and simple foliage. Semi-intensive Green Roofs are the second category and these will typically have a deeper layer of nutrient rich soil and contain shrubs, herbaceous plants and bushes and a thicker layer of grass. The third category of roof gardens is Intensive Green Roofs which will have a very deep soil layer and support a wide variety of plants, bushes, and possibly even small trees.
You may think having a roof garden is funny or amusing, certainly in the city. Too bad this thought is based on ignorance. As already mentioned briefly, a roof garden will absorb the heat from the sun making it much easier on the A/C to cool the interior of the building. Reciprocally, in the winter, the garden prevents the heat from leaving making it much easier to keep the building warm. Some of the employees or people that live in a building with a roof garden may notice this, others may not. But the owners of the building and the people who pay the electric bill will know for sure the attributes of a roof garden.
In the future, cities may have farms stacked up in high rise buildings. Dozens of vegetables and even cattle and poultry and the list continues could all be raised for the good of the city rather than transporting food from distant farms to the city’s grocery stores. This would save wear and tear on the road, help save land space, and certainly save time. So if you think a roof top garden is strange, you may need to open your mind a little.
The International Green Roof Association (IGRA) says that roof gardens are an essential component of sustainable urban development and their use should be encouraged wherever possible.
With a simple Google or Yahoo search, you will be able to find a list of roof garden installers, consultants, and landscapers in your area who can be contacted to discuss the roof garden options available to you.
3.The Positives of Roof Gardens
• In a congested urban setting a traditional ground level garden is usually unviable because of space constraints. Roof gardens offer the option of using idle roof space to create a garden.
• Besides the pleasure of having a garden to unwind in and the health benefits that gardening offers, a roof garden is a great place to entertain.
• Those who work at home or who do not go out much often find that working in a roof garden provides a refreshing and productive change of scenery.
• Roof gardens provide a thick layer of insulation on the roof which can help to make significant reductions in heating and cooling expenses.
• The plants in a roof garden absorb carbon dioxide from the air and reduce the amount of pollution which offers health benefits.
4.The Negatives of Roof Gardens
• The first issue with roof gardens is the building will need to be checked to see if the roof can safely support the weight of a garden.
• The main function of the roof is to keep rain from entering the building. Sloping roofs offer the best protection and drainage. A roof garden requires a flat roof, which restricts the drainage.
• The roof will require special water proofing to ensure that the moisture that accumulates in the soil does not seep into the building below.
• A roof garden can be expensive to install. As per the IGRA, a roof garden can cost between $12 to $24 per square foot, depending on the type of garden planned.
• If you are not interested in gardening or do not have the time, a gardener will have to be employed to care for the garden which is a significant expense.
5.Weigh the Pros and Cons Before Deciding
A roof garden can offer beauty, a place to relax, savings on utility costs and environmental benefits. But the installation and maintenance costs cannot be ignored. Weigh all the factors before making a decision.