England and Wales High Court (Chancery Division) Decisions

IN THE HIGH COURT OF JUSTICE
CHANCERY DIVISION

		Royal Court of Justice Strand, London, WC2A 2LL
		13 June 2012

Mr William Trower QC:

Introduction

1. In these proceedings, the Claimants, acting through their joint receivers, seek a declaration that they are entitled to an easement or easements of light pursuant to the Prescription Act 1832 ("the 1832 Act"), alternatively the doctrine of lost modem grant, with respect to the windows on the north-east façade of a building situated on land known as City Plaza, Cannon Street, Birmingham B2 5EF ("City Plaza"). The Claimants are the registered freehold proprietors of City Plaza, which is registered at HM Land Registry under title number WM332195.
2. City Plaza is bounded to the south-east by Cannon Street, to the west by Needless Alley and to the north-east by New Cannon Passage. The building situated on City Plaza is nine stories high. It is predominantly office space, but there is also some retail space on the upper ground floor. It was constructed between 1987 and 1988.
3. The freehold of the servient land, in respect of which the easement of light is claimed, is registered in the name of the Defendant at HM Land Registry under title number WK65225 ("the Defendant's Property"). It comprises 45-59 (odd numbers) Temple Row, 3-9 Cherry Street and 17A and 18-21 Cannon Street, Birmingham. It is bounded to the south-west by New Cannon Passage. There are two principal buildings on the Defendant's Property, an office and bank building fronting onto Temple Row known variously as St Philips Chambers or 55 Temple Row, and a 20-storey building fronting onto Cannon Street known as Bank House. The Defendant's Property also includes a podium level structure at the south-east end of New Cannon Passage which provides service access to the two principal buildings.
4. The Claimants' freehold interest extends over New Cannon Passage, but the passage itself is a public right of way which separates City Plaza and the Defendant's Property, and which is therefore overlooked by the north-east façade of City Plaza. It is that façade which contains the 69 apertures with which these proceedings are concerned. City Plaza also contains a curved glazed frontage at the northern end of New Cannon Passage. As I shall explain, the same issues arise in relation to some of the windows in that frontage as arise in relation to the 69 apertures on the north-east façade.
5. The Claimants also seek an order for the cancellation of a light obstruction notice first registered by the Defendant's predecessors in title under section 2(3)(b) of the Rights of Light Act 1959 ("the 1959 Act") on 16 May 2008. The Claimants no longer pursue a claim they had originally made for an injunction to prevent what they alleged to be an anticipated infringement of their rights to light. There is undisputed evidence that the Defendant has no current intention to redevelop the Defendant's Property, and the Claimants withdrew this part of their claim shortly before the hearing of a strike out application which was based on that evidence and the recent decision of Sir Andrew Morritt C in CIP Property (AIPT) Limited v. Transport for London and others [2012] EWHC 259 (Ch)

The Issues

6. The principal issue with which I am concerned relates to the true meaning and effect of a conveyance dated 6 June 1967 ("the 1967 Conveyance") made between the Lord Mayor, Aldermen and Citizens of the City of Birmingham ("the Corporation") and the Governor and Company of the Bank of England ("the Bank"). I shall explain this issue (and how it arises) in more detail later in this judgment, but in short summary the relevant question of construction is whether the 1967 Conveyance authorises the owners from time to time of the Defendant's Property to interfere with light or air enjoyed by City Plaza irrespective of the identity of the proprietor of City Plaza, or whether it only authorised such interference for so long as City Plaza was owned by the Corporation.
7. If the authority was limited in the manner contended for by the Claimants, it is accepted by the Defendant that each of the 62 windows on the third to ninth floors, a small square window on the upper ground floor and a single window on the first floor of the north-east façade of City Plaza have been in position for a sufficient period to enjoy a prescriptive right to light against the Defendant's Property. Furthermore, it is also accepted by the Defendant that, if the authority was so limited, City Plaza's enjoyment of light will not have been "by some consent or agreement expressly made or given for that purpose" within the meaning of section 3 of the 1832 Act and that accordingly the proviso to that section is not engaged.
8. As to the remaining nine windows in the north-east façade of City Plaza, there is a relatively limited dispute between the parties as to whether the alteration to the fenestration in about 2006 has had the effect that five of those windows as they now exist (one of which is on the upper ground floor and four of which are on the second floor) have no prescriptive rights to light. It is not in dispute that the remaining four windows are completely new and cannot have acquired any such rights.
9. Both parties agree that, if I decide the first issue in favour of the Defendant, the alterations issue does not arise, because I will have concluded that no prescriptive right to light is enjoyed by any of the apertures on the north-east façade of City Plaza. I have, however, been asked to express my views on this issue in any event, and it seems to me that it is appropriate to do so.
10. I should add that Mr Michael Barnes QC for the Defendant identified a further possible issue as being how any infringement should be approached having regard to the alterations in the windows. During the course or the trial, however, Miss Katharine Holland QC for the Claimants confirmed that her clients only seek declaratory relief as to the extent of their rights. They do not now seek any determination as to what would amount to an interference by the Defendant. It follows that, whatever may have been the position at the time the parties' evidence was prepared, questions of infringement are not now questions that I am asked to decide.

The Factual Background

11. There are only a limited number of facts in dispute. Much of the evidence adduced by witness statement has proved to be non-contentious and a Statement of Agreed Facts and Issues ("the Agreed Statement") prepared by the parties' experts in rights to light has narrowed the questions even further. Both experts gave limited oral evidence; they were Mr Jerome Webb for the Claimants and Miss Elizabeth de Burgh Sidley for the Defendant. They are both highly experienced in their field. Despite the large measure of agreement, it is necessary to explain the factual background in a little detail so that my conclusions can be seen in their proper context.
12. By an indenture dated 13 March 1899 ("the 1899 Indenture") it was provided that it would be lawful for any party then or thereafter having an interest in land which formed part of what is now the Defendant's Property to erect without limit as to height or extent any building, without any interruption or molestation from any party then or thereafter having an interest in land, part of which formed part of what is now City Plaza. The relevant part of what is now the Defendant's Property was coloured yellow on the annexed plan and was called the Penn property. The relevant parts of what is now City Plaza were coloured blue on the annexed plan and (together with other parcels coloured pink and green on the annexed plan) was called the Inge property.The extent of the Penn property and the Inge property and how these two parcels of land relate to the buildings now erected on City Plaza and the Defendant's Property has been agreed between the parties and is identified in one of the plans exhibited at Appendix D to the Agreed Statement.
13. Mutual rights were also conferred by the 1899 Indenture on the owners from time to time of the Inge property, in that they were granted the right to erect any building without limit as to height or extent and to do so without any interruption or molestation from any party then or thereafter having an interest in the Penn property. It was expressly provided that the rights mutually conferred were to run with the land forever.
14. The consequence of what has now been agreed is that those parts of the building constructed on City Plaza which stand on what was the Inge property (being part of the curved glazed frontage at the northern end of New Cannon Passage) cannot enjoy a prescriptive right to light as against the Penn property. That does not mean that those parts cannot enjoy a prescriptive right to light as against other parts of the Defendant's Property, although it is appropriate to record that it is set out in the Agreed Statement that this curved glass frontage obtains considerable light across Needless Alley from St Paul's Churchyard and, if the glazed area remains the same, there is unlikely to be any loss of light as a result of any development of the Defendant's Property.
15. The position is different so far as concerns those parts of the curved glass frontage which do not stand on what was the Inge property. The question of whether the windows in that part of the frontage enjoy a prescriptive right to light depends on the construction and effect of the 1967 Conveyance.
16. As mentioned above, the 1967 Conveyance was made between the Corporation and the Bank. By the time of its execution, the configuration of the land, which is now City Plaza and the Defendant's Property, had changed. The principal effect of the 1967 Conveyance was to transfer to the Bank certain property that I shall call the red land, which included the whole of the Penn property, a small part of the Inge property and other areas of land which together formed the south-west half of what is now the Defendant's Property.
17. Apart from the red land there were two other relevant parcels of land. They were identified in the 1967 Conveyance as the blue land and the green land. Although the copy of the plan annexed to the 1967 Conveyance with which I have been provided is not altogether clear, there is now no dispute between the parties as to the matters described in paragraphs 18 to 21 below.
18. The blue land was already in the ownership of the Bank at the time of the 1967 Conveyance. It formed the north-east part of what is now the Defendant's Property (and also included a small parcel of land further to the south fronting onto Needless Alley, which is not relevant to the issues I have to decide). The dividing line between the blue land and the red land runs through what are now 55 Temple Row and Bank House. The effect of the 1967 Conveyance was that the red land and the blue land came into common ownership. Taken together they comprise what is now the Defendant's Property.
19. The green land was the north-east part of what is now City Plaza and extended over New Cannon Passage. At the time of the 1967 Conveyance, the Corporation retained the freehold interest in the green land. It follows that the apertures which are the subject matter of these proceedings are in the façade which falls within what was the green land, while the red land, forming part of the Defendant's Property, is the land against which the prescriptive right to light is claimed by the Claimants.
20. In addition to the conveyance of the red land, the Corporation, by clause 1 of the 1967 Conveyance, granted further rights to the Bank in the following terms:

"TOGETHER WITH the warehouse and office premises erected thereon and known as numbers 20 21 22 Cannon Street and Temple Courts numbers 55/59 Temple Row Birmingham aforesaid AND TOGETHER WITH (a) the right for the Bank and its successors in title for all purposes in connection with the land and premises hereby conveyed to pass and repass over [the green land] to Temple Row aforesaid at all times until [the green land] shall be incorporated in the Public Highway and (b) full right and liberty for the Bank and its successors in title to build up to the extreme boundaries of the land hereby conveyed and of the land coloured blue on the said plan (hereinafter called "the blue land") the fee simple of which is already vested in the Bank to any height notwithstanding that any such building may interfere with light or air now or at any time hereinafter enjoyed by the buildings for the time being erected on any adjoining adjacent or neighbouring land owned by or vested in the Corporation "

21. There was then a proviso to clause 1, which reserved to the Corporation certain rights of support and rights to build without regard to any interference with light or air. This was expressed in the following terms:

"EXCEPTAND RESERVING unto the Corporation and the Successors in Title to the Corporation for the benefit of the adjoining land of the Corporation shown coloured green on the plan annexed hereto or such part or parts thereof as are capable of benefiting thereby (1) the right of lateral support from the land hereby conveyed for any building or buildings hereafter erected on the said land coloured green and (2) full right and liberty to build up to the extreme boundary of such adjoining land to any height notwithstanding that such buildings may interfere with the light or air now or at any time hereafter enjoyed by the buildings for the time being erected on the land hereby conveyed to the intent that all light or air at any time enjoyed by the land hereby conveyed or any buildings at any time thereon from or over the said adjoining land or any other part or parts thereof shall be deemed to be enjoyed by the leave or licence of the Corporation or their Successors in Title as the case may be".

22. It follows that the rights granted by the Corporation to the Bank and its successors in title by clause 1(b) of the 1967 Conveyance included a right to build on the red land and the blue land without regard to the fact that any such building might interfere with light enjoyed by "the buildings for the time being erected on any adjoining adjacent or neighbouring land owned by or vested in the Corporation It is of importance that the description of the building enjoying the light or air referred to in clause 1(b) is any building "for the time being erected on any adjoining adjacent or neighbouring landowned by or vested in the Corporation". This forms of words does not describe the land enjoying the light as the green land, but uses a broader form of words by reference to the ownership of the Corporation.
23. I heard evidence from a property information manager employed by Birmingham City Council ("BCC"), a Mr Michael McGuinness, on the extent of the land surrounding City Plaza that was owned by the Corporation as at 6 June 1967. Mr McGuinness was called by the Defendant and was able to verify the truth of a witness statement prepared by Mr Andrew Bieganski, BCC's Head of Property Strategy and Information. He was able to identify the relevant property by reference to an annexed plan and also gave a detailed description of BCC's property ownership record-keeping systems.
24. Mr McGuinness' evidence was to the effect that, as at 6 June 1967, the Corporation owned both the green land and other property on the opposite side of Cannon Street from the Defendant's land, as edged red on the plan exhibited to Mr Bieganski's witness statement. He also said that, as at that date, the Corporation had what he called other property owning interests in Birmingham City Centre generally, although presumably these interests were not in "land surrounding City Plaza", which was the description used by the Defendant when seeking relevant information from BCC.
25. It was apparent from Mr McGuinness' evidence that BCC no longer had all of the deeds relating to the land described in his statement, and in particular did not have the deeds relating to two blocks of property forming part of the Corporation's land on the side of Cannon Street immediately over the road from the Defendant's Property. I am satisfied, however, that the evidence taken as a whole confirms that there was land in the ownership of the Corporation as at 6 June 1967, which was not any part of the green land, but which could properly be described as "any adjoining adjacent or neighbouring land owned by or vested in the Corporation" as that phrase was used in clause 1(b) of the 1967 Conveyance. Even if the words "adjoining" and "adjacent" might be said to require an immediate juxtaposition, it seems to me that the word "neighbouring" is capable of extending to land on the other side of the street. Indeed, I think that the phrase taken as a whole means any other land sufficiently proximate to the red land and the blue land (including therefore the Defendant's Property), which is capable of having its enjoyment of light interfered with by a building erected on the Defendant's Property.
26. At some time subsequent to the execution of the 1967 Conveyance the green land, which now forms part of City Plaza, and on which the north-east façade of City Plaza is situated, ceased to be in the ownership of the Corporation. There is no evidence as to exactly when that occurred, but it is common ground that, by the time of construction of the present building on City Plaza, the freehold interest had been transferred from the Corporation, and was held by another of the Claimants' predecessors in title.
27. Planning permission for the development of City Plaza by the erection of the building which is now on the site was granted to the City and County Land Company Limited on 12 July 1984. The evidence shows that development work started in October 1986 and that by the end of February 1988 the original windows had been formed and installed. Leases of parts of the building were agreed with start terms of 29 September 1988 and there is evidence that completion of the office areas and common parts of the building was achieved by the end of November 1988. Practical completion of the entire building was achieved on 16 March 1989. In these circumstances, the evidence is compelling (and both experts agree) that, by the end of 1988, the building that is now situated on City Plaza was substantially completed and the apertures and internal spaces had been formed.
28. On 25 February 2003 and 26 October 2006 planning permissions were obtained for alterations to City Plaza. It was at this stage that the changes to the fenestration I have mentioned above were made. The evidence establishes (and I do not understand it to be disputed) that the following relevant work was carried out to the north-east façade of City Plaza:

a. on the upper ground floor level, an existing circular window was formed into a larger oblong window and a new three-light window was inserted;

b. on the first floor level, three new three-light windows were inserted; and

c. on the second floor level, three new three-light windows and a new single-light window were inserted in replacement of eight smaller windows.

29. Ignoring for these purposes the important issue on the true construction of the 1967 Conveyance, the position of the parties as to the effect of these alterations on the enjoyment of light by the apertures on the north-east façade of City Plaza as against the Defendant's Property is as follows:

a. the parties are agreed that a small square window on the upper ground floor, an oblong window on the first floor and all 62 of the windows on the third to ninth floors of the north-east façade were unaffected and enjoy prescriptive rights to light;

b. the parties are agreed that a new three-light window on the upper ground floor and the three new three-light windows on the first floor of the north-east façade are completely new apertures and do not enjoy prescriptive rights to light; and

c. there is a dispute about the extent to which, if at all, the oblong window on the upper ground floor and the four windows on the second floor of the north-east façade enjoy prescriptive rights to light.

30. The curved glass frontage at the northern end of New Cannon Passage has also been altered since the original construction of City Plaza. The consequence of those alterations is that no prescriptive rights are claimed in respect of the apertures in the ground or upper ground floors of this part of the building. So far as the second to ninth floors of this part of the building are concerned, no prescriptive rights to light are sought in respect of that part of the frontage which stands on what was the Inge property. As to the remainder of the second to ninth floors of the curved glass frontage, the Defendant accepts that the existing apertures enjoy prescriptive rights to light if the issue on the true construction of the 1967 Conveyance is determined against it.
31. On 16 May 2008 the Defendant's predecessors in title (Shop Fund Jersey Nominee A Limited and Shop Fund Jersey Nominee B Limited) registered a temporary light obstruction notice against City Plaza under section 2(3)(b) of the 1959 Act. On 11 September 2008 a definitive certificate was registered on the basis of an application which was expressed to be intended to be equivalent to the obstruction of the access of light to City Plaza across the Defendant's Property which would be caused by the erection on all boundaries of an opaque structure of unlimited height.
32. The registration by the Defendant's predecessors in title had the effect of interrupting City Plaza's enjoyment of light over the Defendant's Property for the purpose of preventing any prescriptive rights to light which had not already been acquired under the 1832 Act from being acquired thereafter. In the present case the Defendant now accepts that, if the point on the 1967 Conveyance is decided against it, 64 of the windows in the north-east façade of City Plaza and part of the curved glass frontage will have acquired rights to light by prescription as against the Defendant's Property.
33. These proceedings were then commenced by claim form issued on 13 May 2009. This was during the period for which the light obstruction notice had effect under section 3(2) and accordingly the Claimants seek declaratory relief and an order for cancellation of the notice under section 3(5). I do not understand it to be disputed that an order for cancellation would be appropriate, anyway to the extent of the claimed right for the benefit of the windows in the north-east façade of City Plaza, if I were to determine the issue of construction against the Defendant. Mr Barnes did not accept, however, that cancellation would be appropriate in respect of any third parties with an interest in City Plaza (such as tenants), who did not protect their position by issuing proceedings.
34. As I mentioned at the beginning of this judgment the relief sought included a declaration that the Claimants are entitled to an easement or easements of light pursuant to the 1832 Act, alternatively the doctrine of lost modem grant. During the course of her submissions, Miss Holland for the Claimants confirmed that it was not her case that the doctrine of lost modern grant gave rise to any different issues from those which arise under the 1832 Act. Accordingly the parties were agreed, and I gratefully accept their agreement, that it was unnecessary for me to explore such differences as may exist between the circumstances in which an easement of light might be established by operation of that doctrine and the circumstances in which it might arise under the 1832 Act. The case was argued, and I propose to decide it, by reference only to the 1832 Act.

Application of the 1832 Act

35. Section 3 of the 1832 Act provides as follows:

"When the access and use of light to and for any dwelling house, workshop, or other building shall have been actually enjoyed therewith for the full period of twenty years without interruption, the right thereto shall be deemed absolute and indefeasible, any local usage or custom to the contrary notwithstanding, unless it shall appear that the same was enjoyed by some consent or agreement expressly made or given for that purpose by deed of writing"

36. Subject to the proviso, the effect of section 3 is that an easement of light will be acquired for the benefit of apertures in a building on the dominant land (in this case City Plaza) if the light has been enjoyed continuously and without interruption for a period of at least 20 years. It is an unusual form of easement in the sense that it exists only with regard to the access to light to defined apertures in a building (as opposed to the dominant land generally) and its acquisition depends on actual enjoyment, not enjoyment as of right: RHJ Ltd v. FT Patten (Holdings) Ltd [2008] Ch 341 ("RHJ") at paragraph 2.
37. Section 4 of the 1832 Act provides that, for any interruption to have the effect of stopping the 20 year period from running, that interruption must have been submitted to or acquiesced in for a year. It is accepted that the effect of this provision is that in practice an aperture becomes capable of acquiring a right to light when it has had at least 19 years and one day of uninterrupted access to light.
38. In the present case it is clear that, with the exception of the four completely new and the five partially new windows described in paragraphs 29.b and 29.c of this judgment, each of the apertures on the north east façade of City Plaza had enjoyed light for a period prior to the registration of the temporary light obstruction notice which would be long enough to give rise to a prescriptive right to light so long as the proviso to section 3 does not apply. In these circumstances, the first question for me is whether the grant to the Bank of the right and liberty described in clause 1(b) of the1967 Conveyance, means that there was a consent or agreement (within the meaning of section 3 of the 1832 Act) by which light was enjoyed by the building situated on City Plaza once City Plaza was no longer owned by or vested in the Corporation. In substance this gives rise to a question of construction of the 1967 Conveyance, but I should first explain how previous cases have approached the construction of the proviso to section 3.
39. The first case cited to me was Willoughby v Eckstein [1937] Ch 167, in which the plaintiff and defendant were both lessees of a common landlord. The plaintiff complained that the defendant had so altered his premises as to constitute a nuisance and an illegal obstruction to some of the plaintiffs windows. The issue, which Luxmoore J had to decide, was whether the plaintiffs access to light was enjoyed by a consent or agreement within the meaning of section 3. Luxmoore J held (at page 173) that the underlying principle was whether the lessee's actual enjoyment of light was permissive throughout the whole term of the lease. The agreement or consent was held to be found in the terms of the plaintiffs lease which constituted, on its true construction, a grant by the lessee to the lessor of the right to build on the adjacent land (including the land leased to the defendant) during the full term of the demise notwithstanding the effect of such building on the light to the premises leased to the plaintiff.
40. The most important modem authority to which my attention has been drawn is the decision of the Court of Appeal in RHJ in which one of the issues was whether it was necessary for the relevant document to contain an express reference to light in one way or the other, for it to be a consent of agreement within the meaning of the proviso. It was argued that an express reference was necessary because the purpose of the consent or agreement must be that of rendering consensual the continued enjoyment of light to any window, and the words "expressly made or given for that purpose " required such a reference to be made.
41. This is a slightly different point from the one with which I am faced but, in rejecting the argument that an explicit reference to light was required, Lloyd LJ discussed a number of earlier cases in which the courts have considered whether the relevant agreement satisfied the requirements of the proviso to section 3. At paragraph 25, he referred with approval to the judgment of Lightman J in Marlborough (West End) Ltd v. Wills Head & Eve (Unreported 20 December 1996), and set out a passage in which the following helpful statement appears:

"... provisions designed to authorise the servient owner at a future date to carry out works or build as he pleases unrestricted by any easement of light in favour of the dominant land and notwithstanding any resultant injury to the light enjoyed... may be construed as consents or agreements permitting the enjoyment of light during the interim period and accordingly (as provided in section 3) preclude any easement arising by prescription under the Act. ''

42. The actual decision of the Court of Appeal in RHJ upheld the conclusion of Lewison J that the agreement referred to in the proviso to section 3 is any agreement the function of which is to prevent the enjoyment of light from being deemed to be absolute and indefeasible within the meaning of section 3. Lloyd LJ described the true principle as follows (at paragraph 44 of his judgment):

"I consider that the phrase ''expressly made or given for that purpose " can be satisfied by an express provision in the relevant document that, on it's true construction according to normal principles, has the effect of rendering the enjoyment of light permissive or consensual, or capable of being terminated or interfered with by the adjoining owner, and is therefore inconsistent with the enjoyment becoming absolute and indefeasible after 20 years. "

43. It follows that, if clause 1(b) of the 1967 Conveyance authorised the owner of the red land and the blue land at a future date to build as it pleased, unrestricted by any easement of light in favour of City Plaza and notwithstanding any resultant injury to the light enjoyed, it may be construed as a consent permitting the enjoyment of light during the interim period so as to preclude any easement for the benefit of City Plaza arising by prescription. Adopting Lloyd LJ's statement of principle, the reason for this is that the authority will be inconsistent with the enjoyment becoming absolute and indefeasible after 20 years.
44. As I have already mentioned it is common ground that the building now situated on City Plaza was erected after the land on which it now stands had passed out of the ownership of the Corporation. Furthermore, the Defendant does not dispute that the building itself, and more importantly 64 of the windows on the north-east façade of City Plaza, have been in existence for a sufficient time prior to the registration of the light obstruction notice for there to have come into existence in favour of those windows an easement of light under the 1832 Act had it not been for the effect of the 1967 Conveyance.
45. The Defendant contends, however, that the right granted by clause 1(b) of the 1967 Conveyance entitled the Defendant (and its predecessors or successors in title) to build on and redevelop the red land and the blue land notwithstanding any interference with light to the windows or apertures in the north-east façade of City Plaza. It is the Claimants' case that clause 1(b) cannot be so construed, because the authority to build notwithstanding any interference with light, was only granted for so long as the land on which the north-east façade of City Plaza now stands was owned by or vested in the Corporation. The point was pleaded in paragraph 7.2 of their Amended Reply as follows:

"The right granted, namely a right to build notwithstanding light interference was a right which existed only in relation to "any adjoining adjacent or neighbouring land owned by or vested in the Corporation The said words do not allow interference with light once such adjoining land is vested in a third party successor and ceases to be vested in the Corporation. "

46. The case was argued on the basis that any consent within the meaning of the proviso to section 3 was co-extensive with the authority to build notwithstanding any interference with the enjoyment of light. In the light of the explanation of the applicable principles given in RHJ, it seems to me that this was an appropriate course for the parties to have adopted. It is only to the extent that such authority continued to exist after City Plaza passed out of the ownership of the Corporation that it could be said that the interim enjoyment of light operated as a consent that is inconsistent with the enjoyment becoming absolute and indefeasible.
47. I also understood it to be common ground that, if the 1967 Conveyance permitted any owner of City Plaza other than the Corporation to enjoy the light over Bank House, the light will have been enjoyed by that owner by some consent or agreement expressly made or given for that purpose by deed of writing within the meaning of section 3 of the 1832 Act, with the consequence that no absolute and indefeasible prescriptive right will have arisen under that section. It follows that, in order to succeed in their claim, the Claimants must prove not just that more than 20 years has passed during which they have enjoyed the light passing over Bank House, but also that such enjoyment has not been pursuant to the terms of the 1967 Conveyance.

The Construction Arguments

48. The Claimants' case has the virtue of simplicity. They contend that the phrase ''any adjoining adjacent or neighbouring land owned by or vested in the Corporation " is not just a method of describing the land, it also makes clear that the rights granted by clause 1(b) operated personally against the Corporation and did not allow the Bank or its successors to interfere with the light enjoyed by the relevant buildings when in the ownership of successors of the Corporation. The principal argument made in support of this submission was that a comparison of the exception and reservation in favour of the Corporation shows that, where the parties intended that land should be benefited throughout enduring ownerships, the land was identified by specific reference (e.g. to a colouring on a plan - "land coloured green" or "the land hereby conveyed'), rather than by reference to the identity of the owner.
49. It was also argued by the Claimants that, where the parties intended that a prescriptive right to light should not arise because of the operation of the proviso to section 3 of the 1832 Act, they said so. In support of this submission, Miss Holland pointed to the phrase at the end of the exception and reservation: "to the intent that all light or air at any time enjoyed by the land hereby conveyed or any buildings at any time thereon from or over the said adjoining land or any other part or parts thereof shall be deemed to be enjoyed by the leave or licence of the Corporation or their Successors in Title as the case may be ". She submitted that the absence of a similar form of words at the end of clause 1 (b) indicated that clause 1 (b) was not intended to have the same effect.
50. Mr Barnes had a number of submissions as to why this approach was wrong. His first submission was based on section 79(1) of the Law of Property Act 1925 ("LPA"), the relevant part of which is as follows:

"A covenant relating to any land of a covenantor or capable of being bound by him, shall, unless a contrary intention is expressed, be deemed to be made by the covenantor on behalf of himself his successors in title and the persons deriving title under him or them, and, subject as aforesaid, shall have effect as if such successors and other persons were expressed. "

51. He contended that the substance of clause 1(b) was a covenant. He said that the Corporation promised that the Bank and its successors in title could carry out any development of the red and blue land whatever its effect on the access of light and air to any adjoining land owned by the Corporation and that this was a burden on the Corporation that, as regards windows on the green land, no prescriptive right to light could arise. Put another way, he submitted that the nature of the covenant was a binding obligation on the Corporation that it could not assert that a prescriptive right to light had arisen. He submitted that the consequence of this was that, in the absence of an expressed contrary intention, the operation of clause 1(b) is not personal to the Corporation, but extends to the Corporation and any other successors in title of the Corporation as regards any adjoining, adjacent or neighbouring land owned by the Corporation on 6 June 1967.
52. In describing the nature and form of the promise, Mr Barnes characterised it as a restrictive covenant, or a promise by the Corporation not to do something. This is relevant to the long-established principle confirmed by the House of Lords in Rhone v. Stephens [1994] 2 AC 310 that the burden of a positive covenant will not be enforced against the covenantor's successors in title and that nothing in section 79 has the effect of causing the burden of a positive covenant to run with the land (per Lord Templeman at page 322). This is to be distinguished from a restrictive covenant, where equity will prevent a successor from exercising a right which, by reason of a promise made by his predecessor in title, was never a right that he had acquired.
53. In support of the argument that clause 1 (b) included a covenant to the effect described, Mr Barnes submitted that whether or not there is a covenant is a matter of substance not form and he relied on MacKenzie v. Childers (1890) 43 ChD 265, 275 and the following passage from Emmett & Farrand on Title (Volume 2 at paragraph 19.002):

"Every obligation which, on a proper construction of a deed, is imposed upon one of the parties thereto amounts to an express covenant by him to perform that obligation, provided the language shows an intention that there should be an agreement between the covenantor and the covenantee to do or not to do the particular thing referred to."

54. Mr Barnes contended that Miss Holland was wrong to submit that clause 1(b) was only to be characterised as the grant of a right or liberty to the owners of the Defendant's Property to build as they wished. He submitted that, merely because a clause operates as a grant, does not mean that it cannot also contain within it a covenant by which the grantor binds himself not to do something which is inconsistent with his grant.
55. On this part of the submission I agree with the Defendant. It seems to me that clause 1(b) is to be construed as imposing on the Corporation a restrictive obligation of the kind identified by Mr Barnes. Put another way, I agree with his submission that clause 1(b) does not just grant a right to the Bank to build without committing a nuisance, on its true construction it also contains a promise by the Corporation that it would take no steps to assert that a prescriptive right to light might arise in favour of the identified land which now includes City Plaza as against the blue and red land, now constituting the Defendant's Property. I do not see why this should not be a covenant relating to any land of the Corporation within the meaning of section 79. Subject of course to questions of construction on the ambit of the promise actually made, equity can in principle prevent the exercise of any purported right (in this case to assert that a prescriptive right to light had arisen), which was not a right that a successor of the Corporation had acquired.
56. In the case of a normal restrictive covenant, such as a promise not to build, it seems from the decision of the Court of Appeal in Morrells of Oxford Ltd v. Oxford United Football Club Ltd [2001] Ch 459 that the effect of section 79(1) is to convert that promise from one which is made by the covenantor into one in which, all other things being equal, equitable remedies are available against an extended class of persons (per Robert Walker LJ at paragraph 35):

"My tentative view, therefore, coinciding, I think, with the judge's, is that section 79, where it applies, and subject always to any contrary intention, extends the number of persons whose acts or omissions are within the reach of the covenant in the sense of making equitable remedies available, provided that the other conditions for equity's intervention are satisfied. Where a restrictive covenant is expressed in the active voice, and section 79 applies, its normal effect is not to turn "A covenants with X that A will not build" into "A and B covenant with X that A will not build". Rather it is that "A (on behalf of himself and B) covenants with X that A (or, as the circumstances may require, B) will not build". "

57. In my judgment, however, this does not justify the conclusion that, for this reason alone, clause 1(b) must be read as extending in its operation to the Corporation's successors in title. The reason for this is that the statutory presumption will always be rebutted where a contrary intention can be found in the wording and context of an instrument. As Robert Walker LJ explained at paragraph 28 of his judgment in Morrells, and it seems to me that this was the ratio of the decision, the statutory words will not be read into the covenant if they are "words inconsistent with the purport of the instrument'. Put another way, it is not necessary for there to be an explicit expression of a contrary intent; it is sufficient if the words are inconsistent with what is otherwise discerned as the true meaning of the instrument.
58. This approach is readily comprehensible in circumstances in which section 79 is concerned with simplifying conveyancing by creating a rebuttable presumption that covenants relating to land of the covenantor are intended to be made on behalf of successors in title, rather than be intended as purely personal (per Robert Walker LJ at paragraph 40 of his judgment in Morrells). Accordingly, in circumstances such as the present, it is my view that section 79 adds little of substance to the real underlying issue, which is whether or not clause 1(b) was intended to be personal to the Corporation in the first place.
59. This brings me to the question of construction of clause 1(b) without regard to the effect of section 79 of the LPA. I can start with the Claimants' submission that, where the parties intended that a prescriptive right to light should not arise because of the operation of the proviso to section 3, they said so. Thus it is possible to point to the fact that, unlike clause 1(b), the exception and reservation in favour of the Corporation for the benefit of the green land spelt out that the enjoyment of light by the buildings on the red land was deemed to be enjoyed by the leave or licence of the Corporation or its successors in title; and that this appears to be an allusion to a consent or agreement of the form referred to in the proviso to section 3.
60. In my view the difference in wording between the exception and reservation on the one hand and clause 1(b) on the other does not have the significance attributed to it by the Claimants. Although not spelt out in a deeming provision in the same terms, it is equally clear (and I think that Miss Holland accepted as much) that the final words of clause 1(b) were also concerned with making provision for at least some application of the proviso to section 3, even if the consent or agreement was limited to the duration of the Corporation's ownership. The reason for this is that there is no other obvious explanation (and none has been suggested) as to why an authority to build in the future, notwithstanding any interference with light then or thereafter enjoyed, might have been introduced into clause 1 at all. As Lightman J explained in the Marlborough case, an authority to build in the future, notwithstanding any resultant interference with the light enjoyed by the dominant land, may be construed as a consent or agreement permitting the enjoyment of light during the interim period and therefore precluding any easement arising by prescription under the 1832 Act.
61. On any view the authority to build given to the Bank and its successors in title by clause 1(b) was intended to relate to the enjoyment of light by certain identified buildings, or more accurately the apertures on those buildings. I accept that the words of identification used by the draftsman are capable of identifying the buildings by reference to the essentially transient question of whether or not the building said to enjoy the consent is or is not in the ownership of the Corporation. It seems to me, however, that they are equally capable of identifying the buildings by reference to the static question of whether or not the adjoining, adjacent or neighbouring land on which the relevant building is erected was owned by or vested in the Corporation at the time of the 1967 Conveyance. As a matter of language, however, and because it is the buildings and their apertures whose enjoyment of light is in issue, it seems to me more probable that the purpose of the words at the end of clause 1(b) is to identify the buildings concerned by reference to their physical status or location (i.e. buildings as buildings), rather than by reference to their ownership from time to time.
62. In any event, it seems to me that there is some significance in the place in which the phrase "for the time being" appears at the end of the clause 1(b). It is tolerably clear that this phrase qualifies the word "buildings", i.e. "notwithstanding that any such building may interfere with light or air now or at any time hereinafter enjoyed by the buildings for the time being erected on any adjoining adjacent or neighbouring land owned by or vested in the Corporation"; it does not qualify the ownership of the land. In my view, if clause 1(b) was intended to have the meaning contended for by the Claimants, much the more natural way of expressing the intention would have been "notwithstanding that any such building may interfere with light or air now or at any time hereinafter enjoyed by the buildings erected on any adjoining adjacent or neighbouring land for the time being owned by or vested in the Corporation
63. The Claimants also submitted that, if the draftsman had intended to use the phrase at the end of clause 1(b) as purely descriptive of the land burdened with the grant of the right to build notwithstanding the interference with the enjoyment of light, it is more probable that he would have used a reference to coloured land (e.g. "the land coloured yellow") rather than a reference to present ownership. I disagree. I think that Mr Barnes was right to submit that one of the contrasts to be drawn in the language of clause 1 is the contrast between the right to pass and re-pass over the green land as granted by clause 1(a) and the right to build notwithstanding the interference with light granted by clause 1(b). It is readily understandable that the draftsman might have had in mind a different way of describing the wider right he wished to grant by clause 1(b) from the more precise geographical description that was required to describe the land over which the clause 1(a) right of way was granted.
64. It also seems to me that it is rather more probable that, as the Corporation then owned other miscellaneous property in the immediate vicinity, the parties considered that it was appropriate for a purchaser in the position of the Bank to acquire the freedom to build to the maximum extent available, i.e. as against all of the Corporation's property. It would not have been a very attractive position for the Corporation to adopt, to have granted to the Bank as purchaser a wide-ranging right to build as against some of the property it held in the immediate vicinity, but then to retain in its capacity as owner of other property the right to assert that such building was an unlawful interference as against that other property. I quite appreciate that a building on the Defendant's Property might affect different parcels of the Corporation's land in different ways, but nonetheless, it seems to me that this consideration counts against the Claimants' construction.
65. At a number of points in her submissions, Miss Holland cautioned against undue speculation as to what might or might not have been in the minds of the parties at the time of the 1967 Conveyance. She also referred me to the decision in Churchill v. Temple [2010] EWHC 3369 (Ch) at paragraph 37, in which the dangers of allowing an overly commercial construction to override the clear language of the instrument were stressed. Of course, I accept that I should not embark on such an exercise, but it seems to me that if the words used are well capable of bearing more than one meaning, the correct approach is to attempt to follow what was said by Lord Clarke in Rainy Sky SA v. Kookmin Bank [2011] UKSC 50 at paragraphs 21 and 30:

"[21] The language used by the parties will often have more than one potential meaning. I would accept the submission made on behalf of the Appellants that the exercise of construction is essentially one unitary exercise in which the court must consider the language used and ascertain what a reasonable person, that is a person who has all the background knowledge which would reasonably have been available to the parties in the situation in which they were at the time of the contract, would have understood the parties to have meant. In doing so, the court must have regard to all the relevant surrounding circumstances. If there are two possible constructions, the court is entitled to prefer the construction which is consistent with business common sense and to reject the other. "

"[30] In my opinion Longmore LJ has there neatly summarised the correct approach to the problem. That approach is now supported by a significant body of authority. As stated in a little more detail in para 21 above, it is in essence that, where a term of a contract is open to more than one interpretation, it is generally appropriate to adopt the interpretation which is most consistent with business common sense. "

66. In striving to find the construction which is most consistent with business common sense, it is useful to test the Claimants' submission by reference to the consequences if they are correct. The effect would be that, for so long as City Plaza remained in the ownership of the Corporation, the owner of the Defendant's Property would have an indefinite right to build without the section 3 prescription period starting to run. On the Claimants' case, time would only start to run from the uncertain and indeterminate moment in the future on which City Plaza was transferred out of the ownership of the Corporation. There would then be the possibility of another 20 years of uncertainty during which the prescriptive right might then arise. While there may well be instances in which commercial men deliberately contract for an uncertain outcome, no reason has been advanced in the present case as to why that should be taken to have been an intended outcome in the minds of the Corporation and the Bank in 1967.
67. It might be said that the Bank and its successors in title could always bring that uncertainty to an end by building or otherwise interrupting the enjoyment of light by City Plaza. That may be so, but, as it is plain that the parties intended to deal in at least some respects with the question of rights to light, I think it is unlikely that they intended to do so in such an incomplete manner. If that had been their intention I think that they would have said so in language that is much clearer than the language they actually used.
68. Mr Barnes also makes a submission based on absurdity. He says that the parties can scarcely have intended that the rights granted to the Bank and its successors in title might only run until sale by the Corporation, when sale by the Corporation might occur at any time with the consequent (and possibly immediate) extinction of the right. In my view this overstates the position. Although I consider that the intention urged on me by the Claimants is unlikely for the reasons described above, I do not consider it to be as absurd as Mr Barnes suggests. I have already touched on the reason for this: on the extinction of the Bank's right by sale, the Corporation's successors in title could still be prevented from acquiring a prescriptive right by an appropriate interruption by the owner of the Defendant's Property, and on the Claimants' case they would have 20 years to do so.
69. Issues of reciprocity were also advanced by Mr Barnes in support of his submission that the final words of clause 1(b) are to be read as defining the buildings in respect of which the enjoyment of light passing over the Defendant's Property was able to be interfered with, as opposed to questions of ownership at the time of the interference. He developed the argument at some length in his written submissions, but in short summary the point he made was that the 1967 Conveyance grants two reciprocal rights to build notwithstanding the effect on the enjoyment of light by the other party's land, and imposes two reciprocal burdens to accept building on the other party's land, notwithstanding the effect on the enjoyment of light by its own land. He says that, in those circumstances, it is extraordinarily unlikely that the parties can have intended that one, but only one, of the burdens subsisted only for the duration of the ownership of one of the parties to the Conveyance.
70. Miss Holland submitted that issues of reciprocity do not assist, not least because it is plain that there is at least one respect in which there is no reciprocity, i.e. that the adjoining, adjacent and neighbouring land is burdened by the Bank's right to build, but that only the green land has a countervailing benefit. To an extent I agree with her, but I do not consider that the reciprocal aspect of the clause really assists one way or the other. On any view the adjoining, adjacent and neighbouring land is burdened for the period of the Corporation's ownership without any reciprocal benefit as against the red land conveyed to the Bank.
71. At first blush, a more persuasive submission was that the Claimants' construction had the virtue of certainty, in the sense that it enabled everybody to ask the simple question: is the burdened land still in the ownership of the Corporation? If it is, it remains burdened with the permission given to the Bank to build. If it is not, it does not. This, Miss Holland submitted, had the virtue of avoiding the need to engage in an historic investigation of title, i.e. an archaeological dig into the question of whether any particular parcel of land said to be burdened by the Defendant's right to build fell within clause 1(b). This consideration meant that the Claimants' construction was inherently more likely.
72. I am not persuaded by this point. If the exercise were to be as simple as the Claimants suggest (i.e. is the land now in the ownership of the Corporation?), it would mean that land which subsequently comes into the ownership of the Corporation could also be caught by clause 1(b). This would be a surprising result, because it would require to be attributed to the parties an intention to burden land not yet held and would in my judgment demand a very clearly expressed intention. If the Claimants' submission is really that clause 1(b) only burdens land which was both in the ownership of the Corporation as at 6 June 1967 and remains in its ownership at the material date in the future, the archaeological dig would obviously still be necessary. Mr Barnes described this as the geographically fluctuating effect of the Claimants' construction; I think that he was right to so characterise it, and in my judgment it points against their case.
73. Accordingly, while there is some force in the Claimants' submissions, I do not think that that they are correct. In my view they place too much emphasis on a comparison between clause 1(b) and the way in which the exception and reservation was drafted, and they take insufficient account of the proper context in which the words any adjoining adjacent or neighbouring land owned by or vested in the Corporation were used. I have therefore concluded that the right to build on the Defendant's Property was not limited to a right as against the Corporation alone. The consequence is that City Plaza's enjoyment of light over the Defendant's Property continued to subsist by the permission granted by the 1967 Conveyance, notwithstanding the fact that City Plaza was not in the ownership of the Corporation; the proviso to section 3 is engaged accordingly.

The Alterations Issue

74. If I am wrong in my conclusion on the true construction of the 1967 Conveyance, the next issue which arises is the effect of the alterations which took place in 2006. As I mentioned the parties have asked me to deal with this point in any event. This issue relates to five windows on the north-east façade of City Plaza: the oblong window on the upper ground floor and the four windows on the second floor. The precise nature of the alterations is apparent from an agreed drawing (numbered 5769-01) which was exhibited to the Agreed Statement, and which was further revised and agreed at trial to take the form of revision G. It is not in issue that the alterations occurred before the time at which the original windows (which these five windows replaced) could have acquired any prescriptive right to light.
75. The Agreed Statement records the agreed expert evidence as to the window on the upper ground floor. This is to the effect that the original small circular window was altered around 2006 so as to become part of an oblong shaped window with a larger total area of glazing. The Claimants' expert maintained that the new window had rights to light where there is a coincidence between the new and the old window.
76. The Agreed Statement also records the agreed expert evidence as to the four windows on the second floor. This is to the effect that parts of the glazing in the new windows are in the same place as parts of the glazing in the original eight windows. The parts that coincide are hatched in green on the attached drawing. The Claimants' expert maintained that the four new windows enjoy rights to light where there is a coincidence with the original windows.
77. The conclusion expressed by the Claimants' expert in the Agreed Statement ("Mr Webb maintains that the right has been acquired by the new window where there has been a coincidence between the old and the new window") was a legal conclusion as to the right contended for, rather than actual evidence on the extent of the light from which a legal conclusion could be drawn. This approach reflected what he said in paragraph 8.2 of his report: "... those windows which were just altered will have continued to enjoy that prescriptive right...".
78. There are, however, other parts of his evidence in which Mr Webb makes clear that what is in truth a legal conclusion is based by him on the coincidence of the light enjoyed as between the new and the old apertures (in particular paragraphs 10.8 and 12.2 of his report, read together with the agreed drawing numbered 5769-01). Miss de Burgh Sidley was asked about this issue in cross-examination by Miss Holland. I understood her to accept that the light received and enjoyed through each of the new windows included some of the same light which was received and enjoyed through the old windows.
79. Although not explicitly spelt out in her report, Miss de Burgh Sidley's acceptance of this point is consistent with the way in which she had always expressed herself. She was careful to focus her evidence on the fact that any light penetration assessment prepared for the purposes of infringement proceedings (i.e. for an injunction or damages) would have to take into account the entirety of the existing openings, but she did not anywhere contend that the alteration to the windows was such that there was not even some partial enjoyment of the same light through an aperture which partially occupied the same space, both before and after the alterations.
80. It is appropriate to record that in my view Miss de Burgh Sidley's evidence does not detract in any way from the question (which is not before me) of whether the construction in the future of any building on the Defendant's Property might cause an actual interference with such light as City Plaza has a right to enjoy, particularly in relation to the altered windows. The answer to that question will depend on whether, taking into account all relevant factors, including the additional light obtained from the enlarged windows, the Claimants are able to demonstrate an actionable interference.
81. Against this background, the Defendant submits that there are two reasons why the consequence of the alterations is that the five windows in issue cannot have acquired rights to light under section 3 of the 1832 Act. The first reason was developed from the principle that, where a window has an established prescriptive easement of light in its favour, and is then altered in some way, the right to light will be lost if the circumstances surrounding the alteration indicate an intention to abandon the ancient light. This principle is described in the speech of Lord Chelmsford in Tapling v. Jones (1865) 11 HLC 290 at page 319, in which he explained that it will be a question in each case as to whether the circumstances satisfactorily establish an intention to abandon altogether the future enjoyment and exercise of the right.
82. It was then submitted by Mr Barnes that, because the question of whether a right has or has not been abandoned cannot arise unless the right exists, and because the authorities do not suggest that any such doctrine applies to inchoate rights during the running of the 20 year period, any significant alteration in a window during the running of the prescription period under section 3 of the 1832 Act, means that the period must start again with the new windows in order to build up an easement of light by a further 20 years of prescription in relation to that altered window. In oral argument Mr Barnes said that this would be the case for all but a de minimis alteration in the relevant aperture.
83. The second reason advanced by Mr Barnes was that, even if the Defendant is wrong in its submission based on abandonment, the Claimants have not proved that there is an identity or substantial identity of the cone of light which enters the original and the new apertures. In support of his submission that this was necessary, he took me to the following passage in the judgment of Cotton LJ in Scott v Pape (1886) 31 ChD 554, 569-70:

"In my opinion the question to be considered is this, whether the alteration is of such a nature as to preclude the Plaintiff from alleging that he is using through the new apertures in the new wall the same cone of light, or a substantial part of that cone of light, which went to the old building. If that is established, although the right must be claimed in respect of a building, it may be claimed in respect of any building which is substantially enjoying a part, or the whole, of the light which went through the old aperture. "

84. Miss Holland submitted that what matters is the use of the light for the duration of the prescription period. If the same cone of light has been used and enjoyed for the full period without interruption, the provisions of section 3 will have been satisfied and no question of abandonment will arise. Put another way there must have been a substantial continuity of the enjoyment of the light throughout the prescription period and, if there has, there will have been no interruption such as to prevent the right from arising under the 1832 Act. Miss Holland also submitted that there was a sufficient coincidence between the old and the new apertures to justify a finding in respect of all five windows that the new apertures enjoyed some of the same light which had been enjoyed by the old.
85. Miss Holland did not show me any authority in support of her submission, but in my view there is some assistance to be gained on this point from the following passage in the judgment of Bowen LJ in Scott v Pape (1886) 31 ChD 554, 572:

"Mr. Barber endeavoured to persuade us that no right could be enjoyed after the lapse of twenty years if there had been any fluctuation in the measure of the access and use of the light during the twenty years. I cannot myself see that the statute warrants any such view. I should have thought that if there has been a use, for ten years out of the twenty, of a small window, which is enlarged during the remaining ten years of the twenty to double its size, the only right acquired in the twenty years was the right to have arrive for the use of your house the minimum portion of the pencils of light which had passed through this smaller structure; because you could not be said to have enjoyed the larger amount of light for twenty years when you had enjoyed it for ten years only - and I should pause for some time before coming to the conclusion that a man after using the smaller access of light for twenty years through the windows had lost his right to all access whatsoever merely because at some time during that period he had fruitlessly attempted to acquire an enjoyment of more. ... What the person who has acquired the right is entitled to is not the window but the free access of such an amount of light as has passed through that window. "

86. This statement has to be treated with some care, both because it was obiter (Scott v Pape was concerned with alterations made after the right had been indefeasibly acquired) and more generally because the judgments of Cotton and Bowen LJJ in Scott v Pape were subject to criticism in Colls v. Home and Colonial Stores Limited [1904] AC 179. That criticism was, however, on the question of whether the right to light extended beyond that which was necessary for the comfortable use and enjoyment of the building in the first place and in my view does not extend to the question of the loss of a right to light (or an enjoyment of light) caused by alteration to the building on the dominant tenement.
87. There is also some guidance to be gained from the decision in Andrews v. Waite [1907] 2 Ch 500 in which Neville J concluded that, even quite substantial alterations in the fenestration during the prescription period were not of themselves material; what mattered was that the light enjoyed should be the same light as that which was enjoyed throughout the 20 year period. Put another way the real test was identity of light, and not identity of aperture. In my view, Andrews is correctly cited in Gale on Easements (18^th edn at paragraph 4-24) as authority for the proposition that "No alteration of a building, which would not involve the loss of a right to light when indefeasibly acquired, will, if made during the currency of the statutory period prevent the acquisition of the light."
88. It follows that in my judgment the Defendant is not correct to submit that any significant alteration in a window during the running of the 20 year period, means that the period must start again with the new windows in order to build up an easement of light in relation to that altered window. I also disagree that there is the substantive difference of approach for which Mr Barnes contends as between alterations made before the expiry of the 20 year period and alterations made after the prescriptive right in respect of the old apertures has been acquired. It follows that, where there is a coincidence between the light enjoyed through the old and the new windows, the right to that light is capable of arising by prescription under section 3 of the 1832 Act. The extent to which it does so will depend anyway in part on the extent of the portion of the new larger aperture which is coincident with the pre-existing window.
89. In my view, the question of whether there is a sufficient coincidence to justify the retention of an enjoyment of the same light will depend on whether, as Farwell J put it in News of the World Limited v. Allen Fairhead and Sons Limited [1931] 2 Ch 402, 406-7, the new façade has "windows to some extent in the same position as the old windows". The point is made by the editors of Bickford Smith and Francis on Rights of Light, the Modem Law (2^nd edn at paragraph 8.54) that a de minimis coincidence will not be enough to preserve the right. In my view a similar principle applies in respect of the coincidence necessary to show that the same light is being enjoyed both before and after the alteration.
90. Applying that test, I do not agree with the Defendant's submission that the Claimants have not proved a sufficient identity between the light admitted through the old and the new windows. If I were to be wrong on the true construction of the 1967 Conveyance, I am satisfied by the evidence I have described above that the green hatched portions of the apertures on the drawing numbered 5769-01 revision G enjoy a sufficient coincidence with the original windows to render them capable of enjoying rights to light arising by prescription under section 3 of the 1832 Act.
91. Of course, this conclusion should not be taken to prejudge in any way the actual extent of the rights enjoyed, nor the question of whether any actionable interference will arise on the construction of any building on the Defendant's Property. If that issue were to arise, it would on the authorities be necessary for the court to consider whether, taking into account the light received from other quarters (i.e. in respect of which no prescriptive right had been acquired), the interference complained of was or was not actionable: Colls v. Home and Colonial Stores Limited [1904] AC 179, 210-211 (per Lord Lindley). Once established, the right to light is a negative easement which prevents the owner of occupier of adjoining premises from building in a manner which has the effect of illegally obstructing or obscuring the light of the dominant tenement; for it to be illegal the privation of light must be substantial (per Lord Macnaghten in Colls at pages 186-7).

Conclusion

92. In the event, however, I do not consider that the Claimants have proved that they are entitled to an easement or easements of light with respect to the windows on the northeast façade of City Plaza. They have not done so because the effect of the 1967 Conveyance is to engage the proviso to section 3 of the 1832 Act in a manner which extends to the Corporation's successors in title.