Roof terrace can be the place for a function, garden space since back or front yard is not available, garden that provides vegetables and herbs or the flowers which specially woman like to have in their home. Roof terrace designed to have functions include broad open areas, swimming pools, dining area, drinking area, lounges etc. Roof can be the only available space to have a garden specially for people live in flats and apartments. As per their interests they can design roof garden to be a flower garden, plant vegetables and herbs, a place with privacy etc.
Besides to above mentioned uses, the green roofs have more benefits to offer. Concept of green roof arose in west Germany few decades ago and now is popular through out the world. The best green roofs include solar power systems which save power costs in the long run. The idea of green roofs is only to use or maximize using organic materials. Unlike, normal roofs, roofs with gardens absorb rain water and it helps to minimize surface runoffs and chances of floods. Overall, roof terrace gardens are valuable piece of environment in a crowded and busy city like London and brings much needed refreshment to whoever visits the place.
The Source : http://plantingblog.devhub.com/blog/2593434-roof-gardens-as-environment-healthy-option-and-refreshment-for-citizens-in-london/