High Court quashes planning permission due to the Board's failure to provide reasons for rejecting daylight assessment methodology.

THE HIGH COURT PLANNING & ENVIRONMENT [2025] IEHC 499 Record No: 2022/898 JR In the matter of Section 50, 50A and 50B of the Planning and Development Act 2000 Between

PALATINE DAC Applicant and AN BORD PLEANÁLA, IRELAND AND THE ATTORNEY GENERAL

Respondents and MOUNT WAY OFFICES LIMITED Notice Party

JUDGMENT of Ms. Justice Emily Farrell delivered the 19th day of September 2025

Introduction

1. The Applicant seeks to challenge the decision of the first named Respondent (‘the Board’)

granting planning permission to the Notice Party (‘the Developer’) for the construction of an office building at 94 and 95 Mount Street Lower and Love Lane, Dublin 2 on 1st September 2022 (ABP Ref 310958- 21).

2. The facts can briefly be summarised from the Statement of Case helpfully provided by the parties.

3. The Applicant is the owners’ management company for the Grattan Hall development which is a residential development adjacent to the site of the proposed development.

4. The Developer applied to Dublin City Council on 16th June 2020 for permission to demolish the existing two 3-storey over basement buildings at 94/95 Mount Street, Dublin 2 and for the construction of an 8-storey over basement office development, with a set-back seventh floor level (Reg. Ref. 2872/20).

5. Members of the public, including members of the Applicant, made submissions and observations on or around 20th July 2020.

6. The Planning Officer completed a report dated 13th August 2020, following which the Planning Authority requested further information by letter of the same date. It was proposed, inter alia, that the Developer would consider reducing the height of the proposed development by at least two or three floors and that a full visual assessment be provided, together with an assessment of the vertical sky component (VSC) for the nearby residential developments to facilitate a full assessment of the impact of the proposed development on the residential amenity of those units and their associated open spaces.

7. The Developer provided the further information on 18th May 2021. As part of the response to a request for further information, a revised proposal was submitted to the Council by the Developer on 18th May 2021, which reduced the building height from an eight-storey over basement office development to a seven-story over basement office development. A Daylight Analysis and Overshadowing Report was also submitted, which is stated to have been prepared using the methodology in the British Standard Lighting for Buildings – Part 2: Code of Practice for Daylighting, BRE, 209, ‘Site Layout Planning for Daylight and Sunlight: A Guide to Good Practice’, Second Edition, 2011 by P.J. Littlefair and the Design Standards for New Apartments – Guidelines for Planning Authorities (March 2018). That report concluded that the proposed development would not cause a negative impact on the neighbouring buildings. The Planning Authority directed that notice be published inviting further public observations.

8. The Applicant and other members of the public made further observations on or around 16th June 2021. The Applicant took issue with the conclusion that the proposed development would not cause a negative impact on neighbouring buildings, including Grattan Hall and the Northumberlands, 113 Love Lane. It was submitted that the proposed development would obstruct the access of sunlight and daylight to Grattan Hall.

9. The Planning Officer issued a report recommending that permission be refused on or about 30th June 2021 for one reason, namely:

“Having regard to the scale, bulk, height and massing of the proposed development and taking into account the established character and pattern of development in the vicinity of the site, the proposed development would constitute a visually discordant feature in the landscape and impact adversely on the residential amenities of nearby properties in terms of overlooking and overshadowing. The development would constitute an incongruous feature and would detract from the visual amenities of the area. As a consequence the proposal would depreciate the value of property in the vicinity, set a precedent for similar type undesirable development and would be contrary to the provisions of the Dublin City Development Plan 2016-2022 and the proper planning and sustainable development of the area.”

10. On 30th June 2021, the Planning Authority decided to refuse permission for that reason, and the Developer was so notified.

11. The Developer appealed the decision on 27th July 2021 and as part of that appeal, an alternative design solution was proposed. Section 1.0 of the appeal states that the Developer was appealing “against the decision of Dublin City Council to refuse permission for the following development under Reg. Ref. 2872/20”. The alternative design solution submitted by the Developer as part of its appeal involved a further reduction in the building height by the removal of one floor, resulting in a 6-storey over basement office development with a reduced internal floor area and reduced plot ratio.

12. The Applicant made observations on the appeal on 23rd August 2021, in which it was submitted that the proposed development would have a serious injurious impact on the residential amenities of the residents of Grattan Hall and of other residential developments in the vicinity.

13. An EIA Pre-screening form was completed by an official in An Bord Pleanála on 30th August 2021, in which it was concluded that EIAR and Preliminary Examination were not required.

14. The Board’s Inspector issued her report on 25th November 2021, recommending refusal for one stated reason.

15. The Board met on 7th June 2022 and decided to grant permission with 14 conditions. The Board Direction was signed on 29th August 2022 and the Board Order was sealed on 1st September 2022.

Summary of main issues

16. The main issues are, in summary, as follows.

17. Core Ground 1 raises the issue of Jurisdiction of the Board. The Applicant contends that:

“The impugned decision is invalid because the Board lacked jurisdiction to make the

decision to grant planning permission in the context of an appeal against a decision of a planning authority involving a unilateral revision of that application seeking permission for a materially different proposed development to that which was refused by the Planning Authority.” (quotations in this section are from the Statement of Case).

18. Core Ground 2 relates to SPPR 1 and SPPR 3 of the Urban Development and Building Height Guidelines. The Applicant contends that “The impugned decision is invalid since the Board unlawfully had regard to SPPR1 of the 2018 Building Height Guidelines and misapplied SPPR3 of those Guidelines.”

19. Core Ground 3 relates to Material Contravention of City Development Plan. The Applicant contends that “The impugned decision is invalid because at no point did the Respondent actually consider whether the proposed development was consistent with the Dublin City Development Plan 2016 to 2022 (the ‘CDP').” It maintains that the proposed development is clearly in material contravention of the CDP.

20. Core Ground 4 relates to daylight and sunlight. The Applicant contends that:

“The impugned decision is invalid since the Developer’s daylight and sunlight analysis was deficient did not correctly apply the methodology set out in the BRE209 and/or EN 10737 standards thereby underestimating the degree of compliance with these standards. It also omitted entirely from its analysis a large number of affected windows in the Northumberland’s apartment building. Furthermore, the Respondent failed to adequately assess the impact of the proposed development on daylight in the surrounding buildings. It also failed to consider the submissions of the observers and the findings of the inspector who highlighted specific deficiencies and omissions in the assessment submitted by the Developer and in particular its non-compliance with Site Layout Planning for Daylight and Sunlight, A guide to good practice (Building Research Establishment Report, 2011) (‘the BRE Guidelines’).”

21. Core Ground 5 relates to EIA Screening. The Applicant contends that:

“The impugned decision is invalid because the Respondent’s EIA Preliminary Examination did not identify a likely significant effect on the environment identified in the planning assessment, namely the serious injury to visual amenities of the area and the residential amenities of the adjoining residential development by reason of overbearing and overshadowing.”

22. Core Grounds 6 and 7 related to challenges to the validity of legislative provisions and were modularised. Core Ground 6 complains that:

“The impugned decision is invalid since it relied on Article 109(2) of the 2001 Regulations as inserted by Article 98 of Statutory Instrument 296 of 2018 European Union (Planning and Development) (Environmental Impact Assessment) Regulations is ultra vires and is not permitted under section 3 of the European Communities Act 1972 and thereby invalid pursuant to Article 15.2.1 of the Constitution ...”.

23. Core Ground 7 pleads:

“The impugned decision is invalid as it relied on section 37(2) of the 2000 Act which actively contravenes the requirements of Articles 1 and 3 of the SEA Directive by allowing the Board to grant planning permission in contravention of the Dublin City Development Plan 2016-2022 ...”.

24. I propose to consider the daylight/ sunlight issue first as, depending on the outcome of that, the other issues may or may not arise.

Daylight/ Sunlight

25. The pleaded complaint regarding daylight/ sunlight standards raises a range of issues, but it is important to note at the outset that these issues include the question of reasons. Para. 32 of the Statement of Grounds pleads:

“32. Secondly, the CDP (§16.10) is clear that “Development shall be guided by the principles of Site Layout Planning for Daylight and Sunlight, A guide to good practice (Building Research Establishment Report, 2011).” As identified by the observers the Developer’s Reports do not in any way comply with the requirements of the Guidelines.

The Board materially erred in law in failing to consider whether the proposed development constituted a material contravention of the CDP in relation to potential impacts on daylight and sunlight and/or in providing reasons as to why permission should be granted nonetheless.”

26. Para. 34 pleads:

“34. Fourthly, the Applicant makes effectively the same point in the context of section 34(10) of the Planning and Development Act 2000. In circumstances where the Board’s Inspector has identified both an unreliability and errors in the evidence presented by the Developer, the Board is obliged to provide reasons as to why it is departing from that element of the Inspector’s Report. The Board signally fails to do so and instead, as above, simply states a conclusion as to an absence of significant negative impact.”

27. It is well settled law that an administrative decision-maker must give reasons for his or her

decision. This is reinforced by section 34(10)(a) of the Planning and Development Act 2000, which states:

“(10) (a) [Subject to paragraph (c) and without prejudice to section 172(1I), a

decision] given under this section or section 37 and the notification of the decision shall state the main reasons and considerations on which the decision is based, and where conditions are imposed in relation to the grant of any permission the decision shall state the main reasons for the imposition of any such conditions ...”

28. It is also well settled that if the Board is disagreeing with its own Inspector, there is a particular obligation to give reasons for the disagreement. Where the Board decides not to follow a recommendation of its Inspector to grant or refuse permission, section 34(10)(b)

requires it to give “the main reasons for not accepting the recommendation in the report or reports to grant or refuse permission”.

29. In general terms, disagreement with a reasoned conclusion of one of the institutional actors in the process such as the relevant Council or an Inspector gives rise to a need for reasons (or, phrased alternatively, means that the issue concerned is a relevant and main issue that requires reasons): see e.g. Sherwin v. An Bord Pleanála [2023] IEHC 26, Clonres CLG v.

An Bord Pleanála & Ors. [2021] IEHC 303; Flannery & Ors v. An Bord Pleanála [2022] IEHC 83. In Clonres, Humphreys J. identified two main reasons for the enhanced duty to give reasons when rejecting the Inspector’s analysis. Humphreys J. stated that while section 34(10)(b) did not apply in that case, “Nonetheless, there is an independent administrative law requirement to give reasons which is enhanced where one is rejecting the inspector's analysis. That is essentially for two reasons: if the Board isn't accepting the inspector's reasons it has to come up with reasons of its own; and secondly, it has to engage with the inspector's rationale.”

30. If the Board did not agree with the Inspector, which was the case here, it would be necessary for the Board to state why. That is particularly so in view of the fact that observations on this issue had been made by the Applicant, and of the position taken by the Planning Authority in the decision which was the subject of the appeal to the Board. The Planning Authority had noted that the BRE report indicates that for residential properties a VSC of greater than 27% is acceptable, whilst noting that this is guidance rather than a rule.

31. In Balz v. An Bord Pleanála [2019] IESC 90, [2023] 3 IR 751, [2020] 1 ILRM 367 O’Donnell J. (as he then was) held:

“It is a basic element of any decision-making affecting the public that relevant submissions should be addressed and an explanation given why they are not accepted, if indeed that is the case. This is fundamental not just to the law, but also to the trust which members of the public are required to have in decision making institutions if the individuals concerned, and the public more generally, are to be expected to accept decisions with which, in some cases, they may profoundly disagree, and with whose consequences they may have to live.”

32. There is also the context that the whole issue arose because of the need to factor in the daylight/sunlight methodology having regard to the status of the BRE Guidelines or Report.

It was submitted, on behalf of the Board that the status of the BRE Guidelines is crucial to the assessment of the adequacy of the reasons given by the Board. It was submitted that the duty of the Board was simply to have regard to the Building Height Guidelines, as SPPR3 of the Urban Development and Building Heights: Guidelines for Planning Authorities did not apply, and that in any event the 27% VSC in the BRE Guidelines is simply a guide. I note that the BRE Guidelines had formed the basis for the methodology used by the Developer’s expert, and nothing in the Board’s decision suggests that it considered the BRE Guidelines to be inapplicable or irrelevant.

33. Observations of participants in a process may range from the relevant to the marginal or even irrelevant. The Board can assess the relevance of submissions in the first instance but within the bounds of what is reasonable (Friends of the Irish Environment CLG & Anor. v.

Minister for Housing, Local Government and Heritage & Ors. [2025] IECA 128) and of course with due regard to other aspects of the process that make certain issues inherently relevant. The fact that an inherently important issue, on which the Inspector came to a

conclusion that the Board chose to depart from, was also the subject of observations, can only reinforce the obligation on the Board to consider those submissions and give reasons in that regard. Hyland J. stated, in Friends of the Irish Environment:

“10. The duty to give reasons does not encompass a duty to respond to all submissions. If the submission is not relevant to the reasons why the decision has been made, then as a matter of logic, a response to the submission does not form part of the reasons and is therefore not covered by the obligation to give reasons. Following Balz v. An Bord Pleanála [2019] IESC 90, the extent of the obligation on the decision maker is to address “relevant submissions” i.e. submissions relevant to the reasons for the

decision. Doing so is sufficient to vindicate the trust that members of the public are entitled to have in decision-making institutions.”

34. To look at it another way, the sunlight/daylight issue was the subject of a number of converging reasons-related obligations – the autonomous need to consider the impact of Ministerial Guidelines, if appropriate, under section 28 of the Planning and Development Act 2000, the fact that it was the subject of submissions which a decision-maker, acting reasonably, would have seen as relevant, and the fact that it was an issue on which a reasoned

conclusion of the Inspector was being departed from. Any one of these factors, and most certainly the fact-specific situation of the latter two, if not all three combined, give rise to an obligation to give reasons for concluding that the Developer’s methodology was adequate. There are no such reasons.

35. The Developer submitted a report from H3D consultants dated 27th July 2021 to the Council concluding that the project met BRE standards for daylight/ sunlight, and submitted a further report to the same effect on appeal. It was stated therein that the same methodology was followed as in the previous report. The same overall conclusion was reached. The Executive Summary of the Results was given as follows:

“The recommendations set down in the BRE report,' Site layout for daylight and sunlight, a guide to good practice', would indicate, for residential properties, that a VSC value of greater than 27% is acceptable. However, a 20% VSC is good for an urban area (per Independent Review - Representation Hearing Report D&P/3067 /03

- Appendix 1)

Of the 98 no. windows analysed, 95% either exceed the BRE recommended level of 20% (in built up areas) or do not reduce to below 0.8 times the exiting value.

A further Annual Probable Sunlight Hours analysis was carried out on Ashford House as the 4 no. windows analysed for VSC failed to meet the guideline levels. This analysis found that all the analysed windows in Ashford house exceeded the guideline levels of sunlight hours meaning there would be an acceptable amount of sunlight.”

36. The Report also stated:

“It should be noted that the guide itself, within the introduction, states that the advice given was not mandatory and the Guide should not be an instrument of planning policy, its aim being to help rather constrain the designer. Although it gives numerical guidelines, these should be interpreted flexibly.”

37. It concluded:

“The Vertical Sky Component analysis of the windows on the faces of the contextual buildings facing the proposed development demonstrated that the proposed development would not cause any cumulatively undue negative impacts on neighbouring buildings with 95% of analysed windows (93 of 98) either exceeding the BRE recommended level of 20% (in built up areas as per Independent Review (Representation Hearing Report D&P/3067/03 - Appendix 1) or not reducing to below

0.8 times their existing value.

It is the opinion of this report based on carrying out a comprehensive daylight and sunlight assessment of the proposed development using simulation modelling and comparing results achieved against the BRE Guide and BS recommended guidelines, the proposed development would not cause any cumulatively undue negative impacts on neighbouring buildings.”

38. These reports were contested by other participants in the process. The submission made by Jim Brogan, Planning and Development Consultant, on behalf of the Applicant dated 27th July 2021 noted that no further information is given in relation to the Independent Review referred to in the Report. As noted in the Developer’s Statement of Opposition, the Independent Review – “Representation Hearing Report D & P/3067/03 – Appendix 1”, dated 18th November 2013, a document which related to an application by London Diocesan Board of Schools, Dalston for a mixed use school and residential development in the London Borough of Hackney. It has been exhibited by Cian Heffernan on behalf of the Developer, but there is no evidence before the court to state whether that document had been provided to the Board, or was available to it. Paras. 4 – 6 of the Representation Hearing Report D&P /3067 /03 - Appendix 1 state:

“Determining a material impact

4 For existing buildings, the Building Research Establishment (BRE) guideline is based on the loss of VSC at a point at the centre of a window, on the outer plane of the wall.

The BRE guidelines state that if the VSC at the centre of a window is more than 27% (or if not, then it is more than 80% of its former value), then the diffuse daylighting of the existing building will not be adversely affected.

5 It should, nevertheless, be noted that the 27% VSC target value is derived from a low density suburban housing model. The independent daylight and sunlight review states that in an inner city urban environment, VSC values in excess of 20% should be considered as reasonably good, and that VSC in the mid-teens should be acceptable.

However, where the VSC value falls below 10% (so as to be in single figures), the availability of direct light from the sky will be poor.

6 With respect to the reduction factor, it should also be noted that whilst BRE guidelines state that a 20% reduction is the threshold for a materially noticeable change, the independent daylight and sunlight review sets out that given the underdeveloped nature of the site relative to its context, this percentage reduction should be increased to 30%, with and upper threshold of 40%.”

39. The Applicant’s Statement of Grounds (paras. 22 and 23) summarise the objections to the Daylight Analysis and Overshadowing Report submitted by the Developer as follows:

“22. Observers before both the Local Authority and the Board identified profound deficiencies in the Daylight Sunlight Reports prepared by the Developer. They noted, for example, that the Developer had simply omitted significantly affected windows, had modelled results on only a small number of unrepresentative windows, had left out critical information in relation to compliance rates and had applied the wrong threshold for the purposes of assessing compliance with the BRE Guidelines. As pointed out by the Observers, none of these shortfalls was remedied by the revised Daylight Sunlight Report prepared by the Developer in respect of its revised option of six storeys over basement. As identified by the Observers all of the previous errors were replicated in this analysis, including a new and erroneous reference to a report prepared for a proposed development in Hackney in London of no relevance to the assessment.

23. They specifically pointed out that there is no 20% recommended threshold in the BRE Guidelines and that, despite the omission of crucial data, the correct failure rate for the one face where the data was provided was much greater when applying the 27% VSC and 0.8 APSH standards rather than the 6.6% failure rate identified by the Developer. In the same vein the Observers pointed out that for apartments on the east side of Grattan Hall (windows numbered 6,12,18, 24,30 and 36) all of these windows would fail the BRE Guidelines, despite the Developer showing only two of them falling below the thresholds. Furthermore it noted that “60 of the apartment windows on the affected northwest side of Northumberland Apartments are not included in the study at all” despite the Developer’s own Shadow Study showing these windows falling into shadow in the afternoon. Finally, it noted omissions from Grattan Hall and the severe impacts on residential amenity for the residents.”

40. The Board’s Inspector summarised the submissions at para. 6.5 of her Report:

“The daylight and overshadowing reports (for the original, further information and alternative option proposals) are incorrect and unreliable, having regard to BRE’s “Site Layout planning for Daylight and Sunlight: A guide to good Practice, 2nd edition, 2011 as required in section 16.10 of the CDP These reports are incomplete and reliant in incorrect methodology and standards. The contention in the appeal that acceptance of twenty per cent VSC instead of the minimum recommended in BRE guidance of 27 per cent is not acceptable and a significant percentage of affected windows were not assessed. There will be significant deterioration in daylight levels at the surrounding apartments resulting in serious injury to residential amenities.”

41. The Inspector in effect upheld some of these complaints and concluded that it had not been demonstrated that the project complied with BRE standards (paras. 7.7.3 – 7.7.6):

“7.7.3. There is no dispute that dwellings within these blocks with windows and /or external amenity spaces facing towards the proposed block would experience diminution in outlook and skylight access as represented in Vertical Sky Component (VSC) and overshadowing or sunlight access.

7.7.4. The applicant has submitted daylight and shadow analysis studies at application stage and a supplement and in respect of the alternative option included with the appeal. However, the potential impacts in terms of effects on vertical sky components.

(VSC) at relevant windows in at adjoining developments are not satisfactorily assessed so that the potential effects impacts having regard to the minimum standards provided for in BRE “Site Layout planning for Daylight and Sunlight –a guide to good Practice”, 2011 to which reference is made in respect of residential development in section

16.17.10 of the CDP is assessed. Impacts on external private or communal spaces were not assessed.

7.7.5. As pointed out by the planning authority the test, in terms of perceptible loss of light is that a VSC in excess of 27% is acceptable and that where there is a reduction to less than 27% with the difference being not less than 0.8 times the pre-existing value, the effect can be deemed acceptable. The assumption is that 20% VSC is acceptable in the assessments in the applicant’s submissions. As stated in the planning officer report, with application the 27% VSC a considerably larger number of windows in the adjacent residential developments would result in a substandard VSC and perceptible loss.

Probable Average Sunlight Hours (PASH) to interiors do not appear to have been comprehensively assessed or impacts on external amenity spaces.

7.7.6. Furthermore, as also previously stated in the planning officer report, there is a lack of survey information with regard to the windows in adjoining properties and the accommodation to be lit and, no design mitigation is included to address impacts. The Analyses submitted, (but considered unreliable) indicated failure of a small number of windows to meet minimum standards post development in VSC. As such it is concluded that it has not been satisfactorily demonstrated that the proposed development would not have undue adverse impact on the residential amenities of adjoining properties having regard to daylight access and sunlight access.”

42. The Board is, of course in principle, entitled to disagree with the Inspector, a point validly made by the Board at para. 30 of its Statement of Opposition. However, as is clear from the authorities considered above, where the Board disagrees with its Inspector, there is an enhanced obligation to provide reasons. The central question here is whether the reasons given by the Board for departing from the recommendation of the Inspector were provided to the appropriate standard.

43. The reasons stated in the Board Direction are:

“Having regard to Dublin City Development Plan 2016-2022 according to which the site location is subject to the zoning objective: "Z6 to provide for the creation and protection of enterprise and facilitate opportunities for employment creation": to the statutory guidance: "Urban Development and Building Heights: Guidelines for Planning Authorities", 2018"; to the central city location, to the established character and pattern of development in the area it is considered that, subject to compliance with the conditions set out below, the proposed development would accord with national strategic planning policy and local policies and objectives for the area, would not adversely affect the visual amenities of the area or seriously injure the residential amenities of residential properties in the vicinity and would be in accordance with the proper planning and sustainable development of the area.

In deciding not to accept the Inspector's recommendation to refuse permission, the Board had regard to the central city location and the pattern of development in the area, the Z6 zoning objective which seeks to ensure that the employment element on site should be in excess of that prior to the redevelopment in terms of numbers employed and/or office space, and national and local policy which seek to develop existing urban sites at higher density, and considered that notwithstanding, that there would be an impact on the neighbouring buildings with regard to overshadowing, that the cumulative impact would not have undue negative impact, having regard to the built up nature of the site and that the proposed development would, therefore, be in accordance with proper planning and sustainable development of the area.”

44. There is very similar phrasing in the Board Order – the only difference of any significance in the first paragraph is the omission of the word ‘residential’ in the second last line. There is no difference in the second paragraph, which sets out the reasons for departing from the Inspector’s report.

45. As appears therefrom, the Board accepted that there would be an impact on neighbouring buildings by overshadowing but found that “the cumulative impact would not have undue negative impact, having regard to the built up nature of the site”.

46. The Board did not give any reasons which explain how it balanced the impact of the proposed development on the pre-existing residential developments in the area, Grattan Hall, Ashwood House and the Northumberlands, Love Lane, with the benefits of the proposed development – in particular the Board did not refer to the extent of the impact of the proposed development, which had been found by the Inspector would amount to a “radical” change in their environs. The Inspector stated, at para. 7.7.1. that “These blocks have been benefitted from (sic) relatively neutral impacts in terms of unobstructed daylight and sunlight access across the site and its existing structures.” There was no assessment of the number of windows which would fail the BRE standard, or whether the 27% or 20% threshold applied. There was no consideration of the extent to which multiple windows

which fell below the 20% (or 27%) threshold were in the same apartment, or of numerous other aspects of the methodology.

47. The Board provided a conclusion, but it is not possible to identify the reason for that

conclusion.

48. Implicit in the finding of lack of unduly negative impact is a finding that the impact could be identified and assessed, which in turn implies rejection of the Inspector’s (and Applicant’s) view that the methodology was so deficient as to preclude a conclusion as to acceptable impacts.

49. In Ballyboden Tidy Towns Group v. an Bord Pleanála, The Minister for Housing, Local Government and Heritage, Ireland and the Attorney General [2022] IEHC 7 Holland J. said at paragraph 77:

“... the Inspector and the Board are entitled to their view and to apply it to their

decision-making. We can clearly infer that the Inspector disagrees with the Planning Authority best placed to know the practical realities of public transport in the area — but we do not in any meaningful way know why he disagrees.”

50. If one asks why the Board rejected the Inspector’s view as to inadequate methodology, an analogous difficulty arises – it can clearly be inferred that the Board disagrees with the Inspector as to whether the methodology is deficient so as to preclude a valid conclusion as to impact — but we do not know in any meaningful way why it disagrees.

51. The leading authority on reasons is the Supreme Court decision in Connelly v. An Bord Pleanála [2018] IESC 31, [2021] 2 IR 752. Clarke C.J. said (paragraph 6.15):

“First, any person affected by a decision is at least entitled to know in general terms why the decision was made. This requirement derives from the obligation to be fair to individuals affected by binding decisions and also contributes to transparency. Second, a person is entitled to have enough information to consider whether they can or should seek to avail of any appeal or to bring judicial review of a decision. Closely related to this latter requirement, it also appears from the case law that the reasons provided must be such as to allow a court hearing an appeal from or reviewing a decision to actually engage properly in such an appeal or review.

52. In practice this amounts to providing the main reasons on the main issues (Balscaddan Road SSA Residents Association Ltd v. An Bord Pleanála [2020] IEHC 586; O’Donnell v.

An Bord Pleanála [2023] IEHC 381) read in the light of the other caselaw I have referred to. In both Balscaddan Road and O’Donnell, Humphreys J. held that micro-specific reasons for sub-issues are not required. I do not consider that explaining how, and why the Board resolved the issue of the validity of the Developer’s methodology in the Daylight and Overshadowing Reports amounts a micro-specific reason or issue. It was necessary to explain why the Inspector’s findings in that regard, and the submissions made on behalf of the Applicant were not accepted. As Humphreys J. stated in O’Donnell: “A decision-maker cannot be required to give a level of reasons that would satisfy the losing party – that would be a fool's errand anyway. What the decision-maker has to do is give the main reasons on the main issues….”

53. I do not consider that a person affected by the decision in this case, such as the Applicant, would know why the Board considered that the developer’s methodology was sufficiently valid to enable it to reach a conclusion as to the impacts of the development in terms of daylight/sunlight. Reinforcing that, I can say that as the court reviewing the decision, the sparse terms of the order and the lack of reasoning does not enable me to actually engage properly with whatever that reasoning might be, since there is no reasoning apparent to that effect.

54. It is therefore not a sufficient response to argue that the impact of a proposed development on the neighbouring residential buildings, is a matter of planning judgement, which it is.

There was material before the Board which was relevant to its decision, but the validity of the conclusions expressed therein had been challenged in submissions. The Developer had relied on the BRE Guidelines, and referred to Appendix 1 – referred to as the Independent Review. The Applicant was entitled to know why the Board reached the decision it did, particularly in light of the findings of the Inspector and the submissions made by the Applicant and others regarding the methodology applied in the reports submitted by the Developer. The Applicant’s submissions in relation to the methodology were relevant to the reason given by the Board for deciding to grant permission - “notwithstanding, that there would be an impact on the neighbouring buildings with regard to overshadowing, that the cumulative impact would not have undue negative impact, having regard to the built up nature of the site”.

55. At para. 29 of its Statement of Opposition, the Board pleads that “That the Board, in granting permission, overall preferred the planning application documentation submitted by the Notice Party developer does not of itself give rise to any legal infirmity or unlawfulness in the Board’s Decision.” That is correct. However, what was missing in this case is the explanation why the Board preferred the material submitted by the Developer, or accepted it despite the submissions made and the findings of the Inspector, with which it patently did not agree.

56. I have not relied on the affidavit or report of Amy Hastings, dated November 2022, in which she set out her professional opinion regarding the methodology utilised by H3D, on behalf of the Developer, in its reports which were before the Board. Whether the Applicant was entitled to rely on a report which was not before the Board, even where that report is limited to commentary on reports which had been submitted on behalf of the Developer was disputed by the Board and the Notice Party. It was not necessary to determine whether that objection was well founded to determine Core Ground 4.

Conclusion

57. The law on reasons has been set out in existing caselaw and is well established. Applying that settled law here, in the fact-specific and case-specific circumstances of the present case, and having regard to the wording of the Board’s decision in this case, I am satisfied that the Board did not give any reasons as to why the Inspector was wrong to conclude that the Developer’s methodology was insufficient to enable the impacts in terms of daylight/ sunlight to be assessed.

58. In those circumstances it is not necessary to decide the other issues.

Order

59. For the reasons set out above, I shall make an order of certiorari quashing the decision of the Board granting planning permission to the Developer for the construction of an office building at 94 and 95 Mount Street Lower and Love Lane, Dublin 2 (ABP Ref 310958- 21) on 1st September 2022.

60. The matter is to be listed before me on 13th October 2025, on which date application can be made for any consequential orders.