Surveyors and Valuers should always be aware of the risk to buildings from trees and identify the risks posed by different species. Cracks in brickwork, uneven pathways or blocked and damaged services will often be associated with a nearby tree. Homeowners, borrowers, lenders and insurers will all have vested interests.
Proximity of trees to a home can damage it in several ways. Falling, broken branches may impact the building. Tree roots could grow directly through, under, or against foundations or external walls or place pressure on foundations. Indirect damage may be caused by moisture being absorbed from the soil, in cohesive shrinkable clay, and have a significant effect on buildings causing subsidence. Even tree removal may result in soil water accumulation, causing ground swelling and heave – especially if the tree’s existence pre-dates the property.
Trees with extensive root systems which are more likely to cause problems include Poplar, Willow, Elm and Oak trees which all suck up large quantities of water. As a general rule, to not be of concern, trees should be located at a distance from the property that is at least equal to the tree’s expected fully-grown height.
Surveyors should always record on their site notes the proximity of trees and take a range of photographs to show the current condition of the property. Just because a tree is close to a house doesn’t always necessitate a specialist report! There may be no need to cut down a healthy tree whose roots are not causing problems.
If a risk exists to a property, due to the proximity of a tree, but there is no evidence of damage, surveyors may not consider it significant for mortgage lending purposes. They should however advise borrowers of the possibility of future damage that could be caused to the building and the services, but that none was seen at the time of inspection. They may decide to advise the borrower to keep the tree at its existing height to minimise potential future risk and stipulate that a tree report is not necessary. In most cases, it is prudent to advise the homeowner to have the tree regularly pruned or pollarded by a qualified tree specialist to prevent it from increasing in size or obtain specialist advice if required.
Buyers should also ask their solicitor to establish whether there are any Tree Preservation Orders associated with their site. TPOs that that may be in place must be complied with and any tree growth maintenance regulations adhered to.
If there is a significant threat due to size, or proximity, or tree associated property damage is evident to the mortgage valuer, they should request a report from an appropriately qualified Structural Engineer or Arboriculturalist. Surveyor generated Specialist Report requests should advise of the tree type, maturity, height and distance from the property and of any known TPOs. Details should also advise whether the tree lies with the boundaries of the plot and describe any associated movement seen.
Trees that could cause of damage near to a property will also be an issue for the building’s insurers. Homeowners should always draw insurer’s attention to a tree of concern when the policy is taken out. If a home is damaged by roots, subsidence or heave, the building’s policy should provide claim cover. However, many policies will not provide cover if a tree root blocks or causes drain collapse.
If a damaging tree is on neighbouring property, specialist legal advice may be required regarding causation, consents and costs. The damage may only be covered by the affected homeowner’s insurance unless negligence or foreseeable nuisance is proven on the tree owner! Any insurance claim may have to be made on the damaged property’s insurance policy, which one could attempt to recover from the neighbour through the small claims court.
Surveyors should be able to provide specific advice on whether to ask for Specialist Reports or not. Where surveyor’s identify tree related settlement or subsidence, they should not recommend tree removal without expert advice. Full insurer backed underpinning of the relevant building section may be required. In many cases the damage to the property itself will need to be remedied in addition to steps being taken to either fell the tree or prune the top of the tree to reduce its transpiration rate.
In the most serious of cases the property may not be considered suitable security for mortgage purposes until works are completed and a certificate of structural adequacy provided.