The report, produced by Livingroofs.org in association with GRO, the Green Roof Organisation and the National Federation of Roofing Contractors, calculated point-of-sales information from suppliers of green roofs, and the volume of substrate material used in UK green roof implementation, and found that the market was growing by 17 per cent each year.
This growth has been mainly fuelled by work in London, because the London Plan specifies that "major development proposals should be designed to include roof, wall and site planting, especially green roofs and walls where feasible."
As a result, currently around 42 per cent of all UK green roofs installed are in London but there are other hot spots for green roofs outside the capital. Southampton Council’s Green Space Factor planning tool has had an impact and there are other areas delivering green roofs, notably Sheffield and Brighton & Hove.
Now green roof practitioners are asking if the new Metro Mayors can have the same impact in Cambridgeshire and Peterborough, Greater Manchester, Liverpool City Region, Tees Valley, the West Midlands and the West of England.
Founder and chairman of the UK Green Roof Organisation Mark Harris says in the report: "Without the major influence of the London Plan and Local Authority planning officers, it’s probably true to say we wouldn’t be celebrating the success of the green roof industry in the same way today. Looking to the future, I have high hopes that the new Mayors of Birmingham and Manchester will look at what has been achieved in the redevelopment of London and adopt, and/or strengthen, the elements of the London Plan related to green roofing.
"Both of these great cities face the same development challenges that London did back at the turn of the century. The evidence contained in this report points to the significant contributions that the green roof industry can make to a city’s redevelopment and growth – socially, environmentally and economically."
Green roof contractors and suppliers have been saying for some time that the market is booming.
Landscape contractor Bridgman & Bridgman, for example, is looking to triple turnover by 2020 and has invested £40,000 in a new green roof nursery on a 0.8 hectare in Bedfordshire. It already specialises in green roofs and expects to focus completely on them by the end of the decade.
But until now there has been no detailed assessment of the value of the green roof market to the landscape industry, or the wider economy as a whole.
The report found that green roofs are now a mainstream technology and provide nature habitats, help urban centres adapt to climate change, reduce the urban heat island effect and cooling buildings alike and managing storm water. In its 2016 UK Climate Change Risk Assessment Evidence Report, the UK Committee on Climate Change (CCC) recognised green roofs had these benefits, adding: "Green infrastructure offers the opportunity to deliver more sustainable solutions so that communities can thrive and people can live healthy lifestyles."
The report authors gathered sales data from major UK substrate suppliers which showed an annual market growth rate of 17.1%. This figure also correlates to an increase of 17.4% in the area of green roofs installed in the London Central Activity Zone. The report also said the market baseline for green roofs was £26.2m versus previous estimates of £17.5m – amounts that even caught the report authors off guard. The report uses the words "surprise" and "larger than expected".
President at European Federation of Green Roof Associations and Livingroofs.org director Dusty Gedge says: "17% is a really good measure of how much the market is increasing, and there are no other markets in the UK which are increasing by 17 per cent. If that happens year-on-year that’s a big market."
He says it was positive to be able to put a research-backed figure on something the green roof community knew already but he adds that while London is one of the world leaders in green roofs that is little understood outside the sector, with little media attention.
"Because it’s not a mainstream policy in the UK the construction industry doesn’t see it as important."
However he is confident that the new Metro Mayors will affect the green roof market positively in their areas, although he is concerned that such a healthy market will attract "cowboy operators".
"It will take three or four years but I think green infrastructure will be important to them. I suspect that all of the five Metro Mayors will have an element of green infrastructure as a very important part of their planning process and green roofs will be part of that.
"It’s a market open to cowboys, so do they want quality green roofs or do they want cowboys? How do we ensure that what’s written in policy is delivered? The people who are specifying, they are not buying quality and it’s not valuable.
"These things are happening but the worry is they’re not getting the advice they need. GI is going to happen and companies are going to be interested in that. It’s how they write their planning conditions and how they are going to deliver them."
Bridgman & Bridgman director Chris Bridgman says the report has been key to highlighting the growth areas within the sector.
"Its research indicates growing confidence through an increase in the market, signalling a potentially exciting future. It also affirms the need to encourage new people into the industry, and to invest further in training and awareness campaigns," he adds.
Metro mayors' impact
"The introduction of metro mayors could have a positive impact on the green roof industry. Their function enables cities to take control of climate change on a local scale, and green roofs are an obvious mainstream technology to help them. Metro mayors will hopefully learn from the successful London Planning Policy and understand the huge benefits green roofs offer, including their ability to manage storm water, recreate lost habitats, reduce urban heat islands, and support healthy and resilient communities."
The report also highlights how developers are becoming increasingly interested in showing biodiversity gains at their projects.
"In dense urban contexts, green roofs are often the solution as we are already seeing in London. Thus, the green roof market is likely to increase year-on-year and shift away from a focus on London. Significant projects are happening in London and elsewhere. The market is still delivering and is likely to show an increase again this year," the report says.
Gedge says that policy and planning was driving developers’ interest but increasingly they were embracing green roofs and using them to sell their properties, with developers saying ‘we should be doing more of this’ in the future.
"Berkeley Homes has a net gain biodiversity policy. That was unheard of 10 years ago. For a property developer to turn round and say that, that’s positive. There’s a cultural change there and I think green roofs are part of that."
"Having a policy such as the one currently in force in London, would indeed ensure that green infrastructure is included within designs, construction and building alterations. However, it appears more and more private developers are recognising the benefits and installing green roofs by choice, which perhaps is an encouraging signal that the UK green roof industry is catching up with its more mature European counterparts."
Bridgman says there is something the sector can do to influence planning policy in other regions, including those that have new Metro Mayors.
"At Bridgman & Bridgman, our current projects and forward order book are distributed across the country, from Stornoway in the North, to Ramsgate in the South East. Year on year towns and cities are realising the benefits of green roofs and incorporating them into their plans. As a sector, we must ensure that we commit to quality installations, which follow GRO guidelines, as this will encourage further take up of the technology," he says.
It is hoped this will be the first report in many annual updates. Its authors are also interested in studying the impact the green roof market has on UK jobs, the potential market for retrofitting, sharing and spreading good skills and looking at the accurate mapping of green roofs across the UK.