Berent v Family Mosaic Housing (incorporating Mosaic Housing Association) and Another

Hearing dates : 20, 21 March 2012

Approved Judgment

The Claimant and Appellant Mrs Berent is and was at all material times the freehold owner of a house and garden, front and rear, at No 18 Highbury New Park in the Borough of Islington. The Borough of Islington was the Second Defendant below and is the Second Respondent on this appeal and cross-appeal. I shall refer to it hereafter simply as "the Borough" or "Islington". Highbury New Park is a tree-lined road—indeed it has been described as an avenue of London plane trees. There are 276 plane trees along its length, on either side. There are over 300 properties on Highbury New Park. Roads lined with plane trees are not typical of Islington. In 2002, according to its then published "Policy for Trees in Islington" the Borough's tree stock was approximately 9,875 trees consisting mainly of smaller ornamental trees. Only a small number of roads were planted with larger trees, predominantly London planes and lime trees. That was a trend started in the Victorian era. Mrs Berent, or rather her subrogated insurers, allege that two of Islington's plane trees were responsible for causing damage to her property in 2003/2004.

Those two trees, mature London planes, at the relevant time stood in the pavement at the front of No 18. T5, as it was identified in evidence at the trial, was to the front and left of the house, as one looks at the house from the road. It was approximately 12 metres from the front elevation and in 2008 was approximately 10 metres high. T7 was to the front right, again approximately 12 metres from the front elevation and in 2008 approximately 15 metres high.

No 20 Highbury New Park, next door to No 18, was at all material times owned by a housing association, to which I will refer hereafter as "Mosaic". At the relevant time there was a mature London plane tree in the front garden of No 20, identified at trial as T4. It was 12.2 metres from the closest part of No 18, which was the front left of that building, again looking at it from the front of No 18. In 2008 T4 was approximately 17 metres high. That tree too was alleged to be responsible for damaging No 18 during 2003/2004. Mosaic was First Defendant at trial and is likewise a Respondent on this appeal and cross appeal.

No 18 was at relevant times surrounded by many other mature trees. One was in the front garden, a mature Tree of Heaven, five metres from the house, approximately 10 metres high in 2005 when it was cut down. As at May 2004 there were in the back garden also a mature false acacia, elder, Indian bean tree and a black locust, the latter two 15 and 22 metres from the house respectively.

No 18 is a four storey house of traditional construction. It has shallow "foundations" at the left rear approximately 6cm in depth. The property sits in deep made ground, mainly of clay, but containing also silt, sand, ash and bricks, to a depth of between 2.1 metres and 2.4 metres below ground level at the front and between 2.5 metres and 2.8 metres at the rear overlying the London clay. At the front of the property the original foundations were proved at 2.4 metres below ground level coinciding with the base of the London clay. The made ground is significantly more permeable than the London clay and with substantial granular content at shallow depths. Those parts of the building founding on made ground rather than natural clay are more susceptible to ground movement due to water ingress. This uncontroversial description I take from the judge's judgment.

It is well known that shrinkage subsidence may occur where trees extract moisture from the soil causing it to shrink—clay based soils are particularly prone to moisture-related shrinkage. Shrinkage compromises the load bearing capacity of the soil. Foundations move downwards sufficient to cause cracking. The clay soil will in any event "shrink and swell" through natural desiccation and re-hydration. Trees can contribute significantly to the problem by the extraction of water through their roots. Trees can both dehydrate the soil and inhibit re-hydration.

Tree roots are not however the only potential cause of subsidence damage. In 2003 and 2004 No 18 faced two additional threats.

Firstly, the combined foul and storm drainage system of No 18 was badly blocked and leaking. Significant leakages during 2003 and 2004 are likely to have affected the weight-bearing capacity of the underlying made up soil above the London clay. This source of damage was not eliminated until the end of 2005.

Secondly, the back garden of No 18 borders onto a deep railway cutting. To the rear of the railway cutting and below it run two tunnels, the up and down Channel Tunnel link railway lines or HS1 connecting St Pancras and the Channel Tunnel. These were constructed in September and October of 2003. The tunnelling gave rise to vibration damage to both the foundations and the drains. Moreover, whilst constructing the "up line" the tunnelling machine broke down in the vicinity of No 18 and for some days its engines were left running.

There is no doubt that No 18 suffered sudden and extensive structural damage between September 2003 and the spring of 2004. It took the form of cracks in both the external and internal walls. It was to both the front and left hand side and to the rear and right hand side. The judge found that Mrs Berent's claim in respect thereof was investigated on her behalf in a dilatory manner between 2003 and 2011.

On 9 July 2009 she issued proceedings against both defendants, followed up on 6 November 2009 by service of Particulars of Claim. Both damages and an injunction were sought, the latter requiring the Defendants to remove T4, T5 and T7 forthwith. The trial took place between 14 and 17 March 2011. In February 2011 the Defendants gave notice that they would remove the trees and they were in fact removed in March. The Claimant nonetheless pursued a modest claim for damages for distress, inconvenience and loss of amenity on the footing that the trees should have been removed earlier. The fact that this claim raised issues distinct from liability for the physical damage occurring in 2003/2004 has I think contributed to the difficulty in understanding some of the judge's reasoning in his judgment, which perhaps elides the two enquiries.

The judge found unequivocally that the major damage to the structure of the house in respect of which the action was brought began to occur in September 2003 and was complete by the spring of 2004—judgment paragraphs 52, 53 and 114. The Particulars of Claim allege that the Defendants are liable for that damage in nuisance and/or negligence, and for present purposes nothing turns on the distinction between the two causes of action. In Delaware Mansions Limited v Westminster City Council 2002 1 AC 321, Lord Cooke of Thorndon observed at page 333 that, in this field, "the label nuisance or negligence is treated as of no real significance" and that in this context, "the concern of the common law lies in working out the fair and just content and incidents of a neighbour's duty rather than affixing a label and inferring the extent of the duty from it." The allegation in the Particulars of Claim is that Mosaic and Islington "wrongfully caused or permitted or continued the roots of the said trees [T4, T5 and T7] to encroach upon the Claimant's premises or extend under the Claimant's said premises. From about summer 2003, and thereafter continuing on a daily basis, the said roots undermined the foundations of the Claimant's said premises and/or withdrew the moisture from the soil under the said foundations thereby causing progressive subsidence of the premises." The subsidence and subsequent damage is said to have been caused by a nuisance constituted by the encroachment or extension of the tree roots and/or to have been caused by negligence.Paragraph 7 of the Particulars of Claim pleads that "the said subsidence and the resultant damage [to the premises] was caused by the negligence of the Defendants, their servants or agents. By reason of the facts and matters aforesaid the Defendants owed to the Claimants a common law duty of care to take such steps as may be necessary to prevent and/or minimise the damage that might occur to the premises by reason of the said trees being in such close proximity to the Claimant's premises. The Defendants are in breach of such duty." Particulars are given of the alleged breach of duty as follows:-

"(1) Failing adequately or at all to consider or heed the risk of damage to the Claimant's property being caused by the roots of the said trees.

(2) Failing to pollard, crown or otherwise manage or control the growth of the said trees adequately or at all;

(3) Failing to prevent the roots of the said trees encroaching upon the said premises and/or extending under the said premises and/or causing or permitting the same to encroach upon the said premises and/or extend under the said premises as aforesaid;

(4) Failing as aforesaid when they knew or ought to have known as a prudent landowner and/or as a local authority that the presence of such a tree...