Flat roofs are constructed for three primary reasons, according to RoofingKey.com. Flat roofs and balconies are commonly constructed for purely architectural purposes, such as to match a distinct style. Some roofs are constructed for mechanical purposes like housing mechanical equipment that cannot be stored elsewhere. Others might serve a more functional purpose such as housing a rooftop garden. In any case, special consideration has to be given to major concerns, such as drainage, in order to ensure safety and the durability of the roof.
Choosing the right materials for your roof balcony is also essential to its survival and your safety. Building materials that are too lightweight are likely to collapse under the weight of construction or under the weight of your visitors. Flat roofs can be constructed from the materials as the rest of the building or home, but using a lightweight and sturdy material such as steel roof decking can ensure that your roof patio will be stable. Roof decking in combination with a concrete surface will provide you with a sturdy foundation for your project.
One of the major problems you may face when constructing a flat roof patio is that if you are not careful in your construction effort, you may create a water trap that retains water that will eventually destroy your patio. To establish a proper drainage system you will need to ensure that the patio is slightly sloped away from its center. A slope of 1/4 inch for every foot of roof from the center line of the roof to its edge should be sufficient for adequate drainage. You will also need to have a minimum of two drains and design the drainage system in such a way that no major water accumulation areas develop.
Properly sealing your roof patio is also essential in the construction process and necessary for its survival. If you have a metal roof underlayment that sits below your patio, it is important that you ensure that you have an impermeable membrane that prevents moisture from getting through the top layer of the patio down to the metal portion of the roof. One of the simplest ways to do this is to apply an ethylene propylene diene monomer or EPDM sealant. This is a roofing sealant that is sometimes referred to as "rubber roofing." It consists of a membrane that will expand and contract with the metal and will prevent leaks from occurring.