If you have read any home improvement magazine or blog through the past couple of years you will have probably noticed several columns about green roofs. While they are yet to reach the popularity of solar panels or a lot of other ‘green’ solutions, more and more homeowners and builders are starting to consider them.
Bearing the above in mind, we’ll now take a look at some of the key questions that green roofs prompt to see if one could be a worthwhile idea for your home.
What is a green roof?
A green roof is exactly what it says on the tin. While the ‘green’ term has been widely used with any concept that is positive for the environment, a green roof is actually green. In simple terms, it’s a garden on top of your roof.
Of course, there are other elements to the roof. They must always have a waterproof membrane, to prevent any water seeping into the internal structure. Some also contain root barriers and other drainage systems to thwart issues that can arise through vegetation.
A green roof can be adopted on practically any type of roof, whether it is pitched or flat. In fact, some green roofs have been installed on skyscrapers – which highlights just how versatile they can be.
What are the benefits of green roofs?
From an energy efficiency perspective, it’s understood that green roofs will slash your bills both in the winter and in the summer. In the case of the former, it goes without saying that vegetation will act as terrific insulation and therefore keep your home much warmer. As for the warmer days, green roofs have been proven to keep buildings cooler and this is the main reason why so many commercial buildings are turning to them, as they do result in expensive air conditioning systems being on for much less time during the day.
Another benefit is associated around the maintenance issues and lifespan. If you have a standard roof, there’s a chance that you will regularly have to perform maintenance tasks and even call in a specialist company, to carry out the jobs for you. Green roofs in contrast require little work and have a much longer life expectancy than traditional roofs – although there are few exact figures to highlight this due to the short amount of time they have been in the market.
One of the biggest advantages with green roofs is their ability to drain storm water. With the UK highly susceptible to large amounts of rainfall, it goes without saying that drainage systems are very important and can make or break some homes. The nature of a green roof means that the water is simply stored in the plants on top of the roof – negating the need for it to be disposed of at ground level. Admittedly, there are times when other drainage options need to be utilised, but in general the roof can deal with most of the drainage. This can actually lower your water bills as well, with some companies removing their surface runoff charge if you can prove that you have mechanisms to reduce the amount of storm water from your property.
And the drawbacks?
Unsurprisingly, most people are put off by the cost of a green roof. The costs will vary depending on the complexity of your home, but the average seems to be between £10 and £15 per square foot. This is much more expensive than a lot of other roof coverings – meaning that many homeowners dismiss the technology almost immediately.
A green roof isn’t always suitable for existing properties either. With such a large amount of vegetation being placed on the building, it must be structurally stable enough to support its new loading. Unfortunately, especially with older properties, this isn’t the case and a green roof simply isn’t viable.
Therefore, while there are a lot more advantages in comparison to drawbacks, the two issues which have just been discussed are rather large stumbling blocks and will regularly prevent homeowners from turning towards a green roof.