Subsidence
Are trees causing subsidence? Cracks in buildings are caused by many factors but in some cases this may be subsidence. In certain circumstances trees have the potential to cause or exacerbate the subsidence by dehydrating shrinkable ground that a building may bear on. Conversely cracking may result from excessive rehydration as a result of indiscriminate removal of trees.
With decades of experience in this field, years in providing arboricultural consultancy to the insurance industry and in advising structural engineers, surveyors and householders, OMC has a level of experience in trees and subsidence that is rare.
Our reports are considered and not lazy, templated reports specifying wholesale and indiscriminate removal of all adjacent vegetation.
This service can extend to third party householders who may be put under a lot of stress by demands from insurers for removal of their often much loved trees. We can analyse the documentation that the demands are based on and consider whether it is justifiable or proportionate.
Our reports would identify all surrounding vegetation, consider the history of the movement and, in conjunction with structural engineers, recommend a course of management which may also involve trial pits, soil analysis, root identification and level monitoring and solutions could involve vegetation management, root barriers or improving poorly specified foundations. Please read our article “Do trees really matter”.
Where property is to be built on ground that is identified to be shrinkable, the possibility of longer term subsidence caused by dehydration of the substrate or heave caused by inappropriate tree removal exists.
For this reason the NHBC (National House Building Council) has specified how foundations should be designed. This is based on the species, water demand capacity and proximity of the adjacent tree population
With its long experience in trees and subsidence, OMC can produced specialised reports with scaled plans for structural engineers, Building Control departments of local authorities and developers identifying all adjacent and relevant trees in order to inform on design and ensure NHBC compliance.
