Why maths is as important as horticulture with BREEAM’s LE credits

Encon Associates landscape architect, Mark Bentley explains the science behind achieving BRE’s aim to enhance the ecological value of new development.

“I have worked on countless BREEAM assessed developments over the last decade, where I’ve been asked to ‘make sure you maximise the points we get for the Ecology credits’.  Easier said than done, particularly as before 2014 the BRE relaxed their insistence on ‘native only’ planting.

“Few can argue against BRE’s endeavour to ‘encourage actions to enhance the ecological value of the site’ and ‘minimise the impact on existing site ecology’.  However meeting the requirements of the Land Use & Ecology section of the 2014 BREEAM methodology often comes down to your ability in mathematics as much as horticulture in order to ‘gain the credits you need’.

“Take an existing derelict site, for instance, which has been left for several years, and is covered in demolition rubble with areas of regenerating scrub and grassland.  A developer, for example a major supermarket chain- a regular customer in recent years, might decide to build a new store on this area. The local planning authority says they must achieve BREEAM ‘Very Good’ to be allowed permission, so the smart move for the developer would be to appoint a BREEAM Assessor who advises that ‘Ecology Credits are the cheapest to get’. A qualified ecologist is then tasked with surveying the site and discovers there are over 30 species of plants on the plot. After this, the landscape scheme is designed, with due thought and attention to appearance, function, plant association and ‘sense of place’; all the ingredients needed for a cohesive, quality landscape.

“Then comes the maths.  Using the LE03/04 Calculator, the ecologist discovers the ‘ecological value’ of the site has changed by minus 15 due to the existing 30 species and full marks cannot be achieved.”

So what’s the solution?

“Early collaboration between the landscape architect and the ecologist can save time and money in the long run by bridging the gap between aesthetics and ecology. Rarely is it possible to retain existing ecology; particularly areas of regenerating scrub in the centre of a site because the unkempt appearance would be incongruous with the expected manicured appearance of the planting within a commercial development.

However, at Encon Associates, we have developed the synergy between designer and ecologist to the point where we can meet all requirements.  Instead of expecting the landscape architect to “shoehorn” as many species as possible into the design simply for sake of BREEAM credits, areas of “species rich wildflower meadows” are created rather than using off the peg grass mixes with few species. 

Instead of stuffing planting beds with as many native shrubs as possible with little thought for future growth and maintenance, let alone aesthetics and good horticultural practice, non-native species “with ecological benefit” are selected.  Using English Lavender (actually a native of France and Italy) for example has the quality to attract bees and insects. The trick is not to approach this as individual disciplines of landscape design versus ecology, but work in tandem.  That’s the secret behind our success.

For more information on how Encon Associates can help with your BREEAM Assessment, particularly to “make sure you maximise the points you get for the Ecology credits”, then please contact us via our website.