New standard values trees in the built environment
As an industry, we have now had time to work with and absorb the changes to the new British Standard BS5837, ‘Trees in Relation to Design, Demolition and Construction’, which took effect on 30 April 2012. It is a well put together document that details ‘a logical sequence of events that has tree care at the heart of the process’.
Main points of BS5837 2012
The standard emphasises the benefits of engaging tree consultants to participate in feasibility and planning, detailed technical design, construction site management, implementation and aftercare. It significantly promotes the proactive role of consultancy in protecting existing tree resources on development sites.
Requirements for initial surveys remain largely unchanged apart from a renaming of ‘R’ category to ‘U’ category. The survey is now classed as part of the feasibility study.
There is greater emphasis on new trees and their importance within a development, in particular their significance in climate change remediation. The standard contains much more information and guidance on incorporating new planting in designs
Tree protection barriers need to be appropriate for the level of construction activity and BS5837 now allows for a lower specification in certain situations.
Post-planning implementation work now needs to include a programme of site monitoring.
Challice Consulting’s viewpoint
The structure of BS 5837 2012 is very different from previous versions, with activities and outcomes linked to the standard work stages of the architectural consultant.
The main change is in the processes that all consultants should follow. The three stages are now much clearer:
STAGE ONE: feasibility and planning,
STAGE TWO: detailed/technical design, which is now completed post-consent, and
STAGE THREE: implementation and aftercare.
The pre-consent work includes the tree survey, identifying design constraints, identifying trees for retention and removal, production of new tree planting and landscape proposals and production of a (draft) tree protection plan.
This reorganisation demonstrates that our role is wider than just giving advice during the preparation and determination of land use planning applications.
With the overall aim of ‘achieving a harmonious relationship between trees and structures that can be sustained in the long term’, the recommendations support our long held view that we can do more to help with environmental performance issues relating to the development of land.
While we continue to provide a fast response, enabling our clients to comply with regulatory requirements under planning law, we welcome the opportunity to extend our services throughout the standard work stages.
Technically BS5837 also now addresses recent changes to building control standards and construction methods.
Additionally, the recommendations value more highly the part trees play in the wider ecosystem and their potential to assist with climate change adaptations. We embrace these changes and identify further benefits to land managers who seek our advice relating to issues of planning, design and management of land, where trees are valued as amenity, biological and economic resources.
However, there is some confusion in the post-planning work, which includes the resolution of any tree protection issues associated with the detailed engineering or service installations and the finalising of the tree protection and tree work arrangements.
Many tree officers are reluctant to condition development that could lead to unworkable building solutions. They prefer to condition adherence to a completed detailed method statement. If the method statement is not completed because there is no detailed engineering or service information and if it then transpires that there is no reasonable technical solution, the result will be that the trees in question will lose out over any alteration to the approved layout.
Having stated that a detailed method statement should be produced as part of the post-consent design work, section 7 of BS5837, entitled ‘Demolition and construction in proximity to existing trees’, says that if construction is necessary inside the RPAs, the method statement should be produced and included in the application to prove that the proposals are technically feasible.
Challice Consulting’s recommended stages
Pre-planning and feasibility: tree survey, issued on the date of the site survey
Tree constraints plans and survey schedules issued electronically in format to suit clients
Planning: arboricultural impact assessment, initial layout impact, and design alterations ending with a draft tree protection plan that includes method statement heads of terms
Detailed design: detailed method statement and final tree protection plan including details of site monitoring and a tree work schedule
Implementation: site monitoring programme and intervention as required.
In essence things should not change dramatically. It is clear that work is necessary at different stages throughout the process and information may have to be presented in a slightly revised format. However, there are parts of the BS5837 standard that are still unclear and will require the adaptation and refinement of the methodology as the process unfurls.