A review of the draft British Standard 5837 Trees in relation to design, demolition and construction

Our Principal Arboriculturist has been busy reviewing and commenting on the draft revision of British Standard 5837 Trees in relation to design, demolition and construction which is proposed to be published in April 2025 and likely to have significant impact on the construction industry.

Although “only” published 12 years ago, it has become apparent that BS5837 (2012) has not been fit for purpose recently and is regarded as somewhat outdated in the light of climate change, habitat loss and BNG, although still being successfully applied to all of our ongoing projects, appreciating the huge step it took from its predecessor that was published in 2005.

BS5837 has been widely used to help both land developers and their design teams as well as the relevant statutory bodies in understanding the extent and quality of tree cover on any site, to ensure tree retention is maximised during the design stage and that physical tree protection is provided during all stages of the project.

However, as with all industry standards, a revision is now due and, reading through comments made on the draft and speaking to colleagues, the proposed changes are welcome by many consultants in the industry.

Whilst there are a few changes proposed to simply align the standard with other statutory documents such as the Environment Act 2021 on Biodiversity Net Gain, and Forestry Commission guidelines on felling licences, there are a number of significant wider changes which, despite still being finalised before its publication, can broadly be expected to entail the following:

• A revised structure of the processes around trees in relation to development projects, closer aligned to assessments such as Landscape and Visual Impact Assessments (LVIA)
• An increased importance of the “iterative process” where tree survey data should be available at the outset of any site design process, with opportunities for redesign following the outcomes of an Arboricultural Impact Assessment, raising the profile of the Arboriculturist within the design team.
• A requirement to record ground conditions around trees to better assess its impact on the shape and size of Root Protection Areas and designs around them
• The introduction of a Veteran Tree Category “V” with a larger Root Protection Area (RPA) proposed for this as well as mature Category A trees (15 x stem diameter rather than 12)
• 15m buffer zones along Ancient Woodland, increased to 15 x stem diameter for larger woodland edge trees
• 2m minimum buffers along all hedgerows
• A requirement to include future crown projections to address increasing importance of canopy cover net gain
• Arboricultural Impact Assessment to consider positive and negative impact, direct and indirect impact on individual trees as well as the canopy cover and tree population, which will also be guided by the projects’ tree planting strategy to assess whether there might be a projected betterment on canopy cover and overall species diversity
• Impact Assessments to also consider in more detail the baseline (national and local policy, legal tree protections), the site’s tolerance for arboricultural changes and cumulative impacts
• Addition of technical protection measures, as well as a “precautionary buffer zones” around Root Protection Areas with some limitations to construction activity

Whilst these are the main changes proposed in the draft new standard, it is hoped and expected that the BS team will take into account the many general and technical comments made by us and our colleagues in the arboricultural industry.

When the final document is published in April 2025, the Arboriculture team at Enzygo will be available to discuss how the changes may affect your future projects, as we appreciate some of those suggested amendments can seem a little daunting to start with. But it may also offer opportunities for sites and new technical solutions will be available to help with our clients’ designs around existing trees.

Contact Verena Meyer, Principal Arboriculturist on [email protected] or 0114 321 5151. Thank you.