Trees as assets : 7 rules for designing with trees

Trees on a site increase visual attractiveness, are great for wildlife and add considerably to property values. Maximising use of existing tree assets in designs will maximise the financial benefits for new developments. Here are NWS’s 7 tips:

  1. To maximise value from tree assets start at the concept stage; here a simple tree survey will suffice: a ‘Tree Constraints Plan’ with ‘Root Protection Areas’ (RPA).
  2. RPAs are minimum core areas to protect your trees; seek specialist advice if RPA conflicts with your design as to whether redesign is required.
  3. On sites with many trees, use BS5837 categorisation to prioritise the importance of individual trees, based on amenity, wildlife and landscape value.
  4. Allow room for future growth based on tree’s longevity; shading plans help design building orientation and fenestration.
  5. Allow for “hidden” issues for trees such as visibility splays, drainage (esp SUDS) and utility connection; trees with faults may need intervention to help them.
  6. An Arboricultural Impact Assessment (AIA) will help when instructing the contractor to protect trees plus organise site clearance, construction and final landscaping and planting.
  7. Find an arborist you can work with, seek their advice early and get their regular input.

If you are interested in how much your trees might add in value to your site, there are various techniques from the Capital Asset Value for Amenity Trees (CAVAT) through to ecosystem services calculations.

Jim calculates a tree’s RPA