Green Roofs (also called eco-roofs or living roofs) have environmental and energy cost-saving benefits that account for their growth in popularity in the UK residential and commercial building sectors.
Popular in Germany since the 1960s, and now established as a roof design in the United States and throughout Europe, they are built up in layers with the top layer devoted to a variety of plants, vegetation, or even trees.
There are, however, a variety of applications where the green roof is modified to suit a particular construction. Some are relatively lightweight, others mid weight and there are roof tops that require the construction to be able to support trees.
Various plants, such as Sedum and perennials, can be used on almost all types of green roofs as they have relatively shallow roots, whereas trees and larger shrubs require heavier systems to support their deeper roots.
S&P Roofing have installed green roofs on both flat and pitched roofs, although there is a maximum recommended slope for roofs that are pitched.
Whether it’s for a commercial, business, public sector or residential design, green roof technology is speeding ahead, and there are many advantages to its installation.
- Roof life is extended. Studies in Germany have shown that green roofs can more than double the life of the roof . The plant material protects the roof from wind blown debris that may cause damage and also shields it from UV radiation. There is less stress caused by the expansion and contraction from extremes of temperature.
- The environment’s water quality is improved. Green roofs control storm water runoff as the water seeps into the plant roots and soil, even when there is heavy rain. A typical green roof can retain up to 50% of a one inch rainfall, thus greatly reducing the water runoff. Any water which is released is done so at a slower rate, meaning less erosion and pollution.
- Green roofs improve the environment’s air quality as they retain airborne pollution particles.
- Green roofs reduce energy costs. Most roofs reach high temperatures in hot weather and this can be even higher in urban areas. The plants, however, absorb and temporarily retain roof heat, releasing it into the atmosphere as temperatures cool. The heat is not transfered to the building interior, keeping the inside cooler, reducing air conditioning needs and costs. More heat is retained during winter, thus reducing central heating costs.
- Green roofs reduce noise – for example from ‘rain hammer’- a particular benefit in school or hospital buildings.
- Green roofs create more wildlife habitats, especially in urban areas where bird and insect life is encouraged.
- The appearance of green rooftops on residential, commercial, business or public buildings greatly improves the aesthetics of our landscapes. Roof design can be modified to suit the local surroundings.
Overall, green roofs can do many positive things for our environment as well as giving cost saving benefits, and S&P Roofing will be pleased to advise on the most appropriate and cost-effective design and installation to suit an existing or new-build project.