How to hit BNG targets without limiting development space & ROI

When it comes to new site developments, planning policy encourages developers, architects, and landowners to leave the biodiversity of a site in better condition than it was before - this is known as Biodiversity Net Gain (BNG).

Historically, the environmental effects of construction were assessed purely by professional judgement. However, local planning authorities are increasingly asking for, and expecting, new projects to demonstrate biodiversity net gain clearly, using a biodiversity metric. In fact, Biodiversity Net Gain is now likely to receive Royal Assent in Autumn 2021 as part of the Environment Bill.

So, if BNG affects you and your business, we’re here to help. Here’s our advice on how to hit BNG targets without limiting your development space and return on investment.

Explore green infrastructure

In order to successfully meet BNG targets, many developers are looking for ways to include sustainable features without compromising on development space.

While some opt for larger, less space efficient options such as ponds, others consider more cost-effective and less intrusive alternatives.

For example, instead of sketching in a pond or habitat bank that needs to be made way for, green infrastructure options like living walls and green roofs can be called upon, leaving more space for the building(s) to be constructed.

In short, living walls and green roof offer a no-compromise solution to meeting BNG targets.

So, let’s explore living walls and green roofs in further detail and explore how they offer a solution without limiting development space and return on investment.

Living walls for Biodiversity Net Gain

Living walls are vertically built green structures with vegetation that can be installed to, or integrated into the façade, as well as interior walls of a building. They include a growth medium such as soil, plants, and usually integrated with a hydration and fertigation delivery system.

But what makes living walls such an excellent choice when it comes to Biodiversity Net Gain?

Because they can be installed on or into external facades, unlike traditional horizontal landscaping they provide a way to counteract any environmental concerns without needing to use extra space. Living walls can easily be planned leading up to a new development or installed onto an existing building for several environmental benefits. These include:

• Creating additional habitats for wildlife
• Removing air pollutants
• Reducing urban temperatures
• Providing a rainwater buffer

Green roofs for Biodiversity Net Gain

Green roofs are similar to living walls, featuring the same benefits and effectiveness.

They focus more on intercepting rainfall though, helping to prevent issues with flooding in urban areas. Green roofs are also known to protect the membrane of a roof from the elements, increasing the lifespan of the roof from the average of 20 years up to 70.

By covering what’s usually a wasted area of a building, green roofs can be extremely worthwhile, helping to comply with environmental regulations and building standards.  It’s worth nothing however that every green roof provides different value to biodiversity, and therefore affects your net gain scoring.  Exploring the benefits of each with an expert before making your decision is hugely important to not only ensure you hit the targets, but to ensure long-term biodiverse value too.

Two useful BNG resources

Our two guides recently developed with the environmental team at AECOM help you do just that.  Detailing how green infrastructure systems can be used and designed to reach the desired biodiversity units delivered, describing the features of these systems alongside illustrations so they are easier to identify, and detailed case studies help you make an informed decision.  In the second guide, we cover the technical information on design, installation and how to ensure longevity with the main GI systems.

We recommend these guides for ecologists, consultants and architects working with BNG.  You can access these two free resources here.

(Both guides have been approved by Defra, Natural England, BRE and UKHab.  You can be sure to be using solid information!)

Achieving BNG targets with Viritopia

At Viritopia, we specialise in providing living wall and green roof systems for those looking to offset developments and achieve Biodiversity Net gain. Our systems offer an effective solution, without needing to invest in additional land such as ponds and habitat banks. So why not contact our expert team at Viritopia today. We’ll let you know how the installation of our green infrastructure systems can be used for your project’s long-terms success.