The Advantages & Disadvantages of Green Roofs

Whether it’s because of an emphasis on nature and the environment or just because it looks unique, green roofs have become increasingly popular for both commercial buildings and regular homes here in the UK.

While they’re not dominating the skyline right now, there are more and more little spots of green popping up. So this month at Roofer UK, we thought it would be worth exploring what a green roof is, along with the advantages and disadvantages if you’re thinking of having one yourself.

What is a green roof?

While many people have added solar panels to their roof for green, renewable energy, a green roof is actually far more literal. By introducing grass, plants and vegetation to a roof, you create something unique, natural and green in colour. It’s a trend that is thought to have begun with sod roofs in Scandinavian countries before being adopted more wholly in Germany in the 1960s.

Set upon a waterproof membrane, you apply a layer of soil to your preferred depth depending on the design and structure of your roof. The depth of the soil will dictate which plants and grasses can be sustained, both in terms of nutrients and the weight added. Often, these categories are broken down into two types: “intensive” green roofs, if they’re deeper than 20cm, and “extensive” green roofs if they are shallower.

The arrangement and choices of flora can be as wild or as manicured as you please, with some commercial buildings using a green roof as an additional recreational space for staff, guests or tenants.

All this begs the question, is it a good idea or a bad one?

The advantages of a green roof

Here are the main advantages of a green roof:

  • It’s a great insulator – Since homes lose a lot of heat through the roof, adding a green layer can help to retain warmth and even reduce noise from the outside.
  • Gives back to nature – Offering a safe space for ecological habitats, a green roof makes more room for insects and wildlife that may have been cut back elsewhere.
  • Protects your roof – Ordinarily, your roof is exposed to the elements, but with a natural layer over the top, it will preserve your roof for longer, protecting it from fluctuating temperatures and UV rays.
  • Improves air quality – Poor air quality has contributed to thousands of deaths in the UK, so with greenery on your roof, you’re helping to reduce the levels of sulphur dioxide, nitrous acid and dust particles in the air.
  • Helps with drainage – Since a green roof will absorb rainwater, it takes some of the pressure off your drainage system on the ground level and goes some way to preventing flooding if enough people adopt the system.

The disadvantages of a green roof

Now for some of the main disadvantages of a green roof:

  • Increased weight on the roof – For your roof to withstand the additional weight of soil, plants and the rainwater it will absorb, you may need to invest in improving the structure of your roof.
  • Extra maintenance needed – While a green roof only needs a little bit of extra maintenance, it’s time you need to ensure you can invest — especially if you’re intending to use the space on a commercial building.
  • Potential for weeds – As with any garden, all green roofs could develop weeds as part of the greenery. This may bother some people, but if you’re wilding your roof, it may not be a huge issue with a little of the aforementioned maintenance.
  • They may attract birds – Again, while the attraction of birds to your green roof might be appealing to some, it’s all a matter of preference and whether you’re keen to give sanctuary to some of the local wildlife, should they choose your roof as their roost.

 

So there you have it, a trend that has made its way from mainland Europe to the UK that offers to boost your green credentials in every sense of the word. Whether it’s suitable for you and your building is something for you to consider, but when it comes to roof repairs, re-roofing or emergency roofing services in London, Watford, Hampstead, Highgate and the surrounding areas, look no further than Roofer UK. We have over 20 years of experience and come highly regarded by our clients for our reliability and professionalism.

Call today to discuss any of our roofing services with our expert team.