A green roof, or living roof, is a roof system that performs all the functions of a conventional green roofing while simultaneously providing a number of significant additional benefits to the environment and to the user.
Green roof construction will treble the lifespan of your underlying roof membrane (eg asphalt or built-up felt). Heat and UV exposure accelerates aging of bituminous materials, and the diurnal British climate (warm days and cold nights) places added stress on such membranes. Greening your roof greatly diminishes the exposure of the waterproofing to the elements, meaning a well-built extensive green roof should last 50-100 years, rather than the 15-25 years (at best) of conventional bituminous materials.
There is also a wealth of research showing that green roof benefits include saving money and reducing energy use by helping keep buildings cool in summer, and warm in winter. The mass of the growing medium provides a greater thermal mass that takes much longer to heat than a conventional roof, reducing the need for air-conditioning in the summer. Simultaneously, however, the plants and substrate cool the building environment through transpiration. This is the opposite of the normal cycle in buildings without vegetated roofs – typically they heat up very quickly during the day and require air-conditioning to cool them, then lose heat much more quickly during the night, requiring heat input the morning. A corollary benefit of green roofs is that they contribute to reducing the urban heat island effect. The more green roofs there are the better!
As with any garden, each living roof is unique and the viability of the habitat is dependent on many variables including climate, exposure, soil and plant type, and initial maintenance. With these variables in mind, Organic-roofs can transform your conventional roof into a visually arresting, environmentally sympathetic and low maintenance space.
At Organics we can design and install green roofs for flat, pitched and even arched roofs