In the last quarter of the 20th century, house expansion geared more towards the vertical. The trend could have been brought about by the migration of young professionals into the city. Suburban living has its perks but for an idealistic and adventure -seeking young adult, the city's lure is just too much to resist. Flats and apartments have very limited space. However small and constrained the space is, there is still a need for the flat-owner to build a quiet little nook for relaxation. The concrete jungle might not have much to offer in terms of a plot of land for a simple garden but urbanites are literally looking up to build their gardens, on the rooftop.

A rooftop garden can help you de-stress from the daily pressure and grind of living. Aside from the garden feeding your senses, you will also have the opportunity to have your very own "green" area to plant whatever you want. You can plant flowers and greeneries to help build a habitat for the birds and other insects. You can opt to grow a vegetable patch and somehow support urban food production albeit on a much smaller scale. The plants and flowers that you grow can reduce carbon dioxide emissions thereby contributing to improving the quality of air. The rooftop garden can help insulate the building thereby contributing to saving energy. The lush greenery of a rooftop garden can also absorb rain water and therefore help storm water runoff. If you were the owner of the building, a wonderful and peaceful rooftop garden can increase the value of your property.

Currently, there is a law passed in Switzerland that a new structure should be so designed that the green area occupied by the structure's footprint could and should be "moved" up in the roof. If all new constructions will do this, then maybe global warming could be arrested.

You can "green" the rooftop anyway you please. However, you should ask the landlord as to any regulations relating this. It is also a good idea to ask the local building official if there are special permits and regulations pertaining to building a rooftop garden. If you plan on laying out a bed of green grass and dwarf trees, you should ask a qualified engineer if the rooftop can hold such load. This is so because wet soil and grass could weigh 80 pounds per square foot.

For a hassle-free rooftop garden, think pots and lightweight materials. Use plastics, fibreglass, pinewood, balsa wood for the rooftop garden. You can just plant flowers in pots and big circular plastic containers. Arrange them artfully into groups making sure that each group has a category. If you need a raised platform of some sort, try building one using pine wood. Avoid the use of bricks and clay tiles as they are quite heavy. A rooftop garden will not be complete without a set of outdoor furniture. Choose one that is weatherproof and make sure there is a spot in the rooftop where you can store the furniture in case the weather gets really nasty. A garden building on the rooftop will be an ideal space to store other garden materials too.