Land and Environment Court New South Wales Medium Neutral Citation: Lizzio v Mosman Municipal Council [2022] NSWLEC 1030 Hearing dates: 17-18 January 2022 Date of orders: 25 January 2022 Decision date: 25 January 2022 Jurisdiction: Class 1 Before: O'Neill C Decision: The orders of the Court are: (1) The appeal is dismissed. (2) Development Application No. 8.2020.122.1 for alterations and additions to an existing dwelling at 19 Dalton Road, Mosman, is refused. (3) The exhibits, other than Exhibit 1, are returned. Catchwords: DEVELOPMENT APPLICATION – alterations and additions to a semi-detached dwelling including first floor addition – insufficient environmental planning grounds for a written request to vary the floor space ratio development standard – contravention of the wall height development standard – proposal does not maintain the traditional scale and character of the existing pair of attached dwellings – impact on the heritage values of the heritage conservation area Legislation Cited: Environmental Planning and Assessment Act 1979, ss 1.4, 8.7 Land and Environment Court Act 1979, ss 34, 34AA, 39 Mosman Local Environmental Plan 2012, cll 4.3, 4.3A, 4.4, 4.6, 5.10, 6.6, Sch 5 Cases Cited: Four2Five Pty Ltd v Ashfield Council [2015] NSWLEC 90 Initial Action Pty Ltd v Woollahra Municipal Council (2018) 236 LGERA 256; [2018] NSWLEC 118 RebelMH Neutral Bay Pty Limited v North Sydney Council [2019] NSWCA 130 Wehbe v Pittwater Council (2007) 156 LGERA 446; [2007] NSWLEC 827 Woollahra Municipal Council v SJD DB2 Pty Ltd [2020] NSWLEC 115 Texts Cited: Mosman Residential Development Control Plan 2012 Category: Principal judgment Parties: Alison Lizzio (First Applicant) David Lizzio (Second Applicant) Mosman Municipal Council (Respondent) Representation: Counsel: A Hill (Applicant) S Patterson (Solicitor) (Respondent) Solicitors: Pavey Pyliotis Lawyers (Applicant) Wilshire Webb Staunton Beattie Lawyers (Respondent) File Number(s): 2021/290009 Publication restriction: No Judgment 1. COMMISSIONER: This is an appeal pursuant to the provisions of s 8.7(1) of the Environmental Planning and Assessment Act 1979 (EPA Act) against the refusal of Development Application No. 8.2020.122.1 for alterations and additions to an existing dwelling, including a first floor addition (the proposal) at 19 Dalton Road, Mosman (the site) by Mosman Municipal Council (the Council). 2. On 25th October 2021, the Court granted the applicant leave to amend the application to rely on amended plans, and the amended application was uploaded on the NSW planning portal. 3. The appeal was subject to conciliation on 17 January, in accordance with the provisions of s 34AA of the Land and Environment Court Act 1979 (LEC Act). As agreement was not reached, the conciliation conference was terminated and a hearing held forthwith, pursuant to s 34AA(2)(b)(i) of the LEC Act. 4. The applicant did not consent to the admission of evidence given during the conciliation conference in the hearing, pursuant to s 34(12) LEC Act. Issues 1. The Council's contentions can be summarised as: * The proposal is inconsistent with the aims of the Mosman Local Environmental Plan 2012 (LEP 2012) because the proposal does not maintain the amenity of the neighbouring properties; * The proposal is inconsistent with the R2 zone objectives of LEP 2012; * The proposal contravenes the wall height development standard in cl 4.3A of LEP 2012 and the applicant has not provided a cl 4.6 written request to justify the contravention; * The proposal results in excessive bulk and scale and its failure to comply with the floor space ratio (FSR) development standard, results in a development that has unacceptable adverse impacts on neighbouring properties; * The proposal fails to provide adequate landscaped area and does not satisfy objectives (1)(a) and (b) of cl 6.6 of LEP 2012; * The proposal would have an adverse impact on the Killarney Estates Heritage Conservation Area (Killarney Estate HCA); and * The proposal is not in the public interest. The site and its context 1. The site is on the northern side of Dalton Road, with rear access from Dalton Lane. The site area is 253.4m2 with a 6.86m frontage to Dalton Road. The site falls from the street front to the rear, and from east to west. 2. The site contains an existing single storey semi-detached dwelling. The attached dwelling to the west at 21 Dalton Road is also single storey. The attached dwellings have a tiled roof with a central roof ridge over the party wall, gables at the street-front elevation, and rear skillion metal roofs. 3. The existing dwelling has a rear deck raised above ground level as a result of the fall of the land. There is a driveway in the rear setback accessed from the laneway. The proposal 1. The proposal is for alterations and additions to an existing single storey semi-detached dwelling, including the following: * First floor addition including two bedrooms, study, bathroom and rear balcony. * Alterations and additions to the ground floor including a rear addition and new rear balcony. * Single garage at basement level accessed via the rear laneway. 1. The roof over the first floor addition is raised above the existing ridge by 500mm over the party wall and is tiled, with a partly concealed flat metal roof. The new roof includes gables to the east and a rear gable. The eastern gables approximately align with the eastern most façade of the existing dwelling (DA 17 and DA 22). Planning framework 1. The site is zoned R2 Low Density Residential pursuant to LEP 2012 and the proposal is permissible with consent. The relevant objectives of the R2 zone, to which regard must be had, are: • To retain the single dwelling character of the environmentally sensitive residential areas of Mosman. • To maintain the general dominance of landscape over built form, particularly on harbour foreshores. • To ensure that development is of a height and scale that seeks to achieve the desired future character. • To encourage residential development that maintains or enhances local amenity and, in particular, public and private views. • To minimise the adverse effects of bulk and scale of buildings. 1. The height of buildings development standard for the site is 8.5m (cl 4.3 and Height of Buildings Map Sheet HOB_002 of LEP 2012) and the proposal complies with the height of buildings development standard. 2. Clause 4.3A of LEP 2012 is in the following terms: 4.3A Height of buildings (additional provisions) (1) This clause applies to all land in a residential zone to which a maximum building height of 8.5 metres applies as shown on the Height of Buildings Map. (2) The consent authority may refuse development consent for the erection of a building on land to which this clause applies if the building has more than two storeys above ground level (existing). (3) However, the consent authority may grant development consent for an additional storey in the foundation space of an existing building on land to which this clause applies if the consent authority is satisfied that the building height and bulk is of an appropriate form and scale. (4) A building on land to which this clause applies must not have a wall height, at any point of the building (other than at a chimney, gable end or dormer window), that exceeds 7.2 metres. (5) In this clause— dormer window means a window in the roof plane that measures no more than 25% of the width of the roof in that plane. wall height means the vertical distance between the ground level (existing) and the underside of the eaves at the wall line, parapet or flat roof, whichever is the highest. 1. The FSR development standard for the site is 0.5:1 (cl 4.4 and Floor Space Ratio Map Sheet FSR_002 of LEP 2012). The objectives of the development standard for development on land in the R2 zone, at cl 4.4(1) of LEP 2012, are: (i) to ensure that buildings are compatible with the desired future character of the area in terms of building bulk and scale, and (ii) to provide a suitable balance between landscaping and built form, and (iii) to minimise the adverse effects of bulk and scale of buildings, (iv) to limit excavation of sites and retain natural ground levels for the purpose of landscaping and containing urban run-off, 1. The site is within the Killarney Estate HCA (Heritage Map HER_002 of LEP 2012 and Sch 5 to LEP 2012). Clause 5.10 Heritage Conservation has the following objectives: (a) to conserve the environmental heritage of Mosman, (b) to conserve the heritage significance of heritage items and heritage conservation areas, including associated fabric, settings and views, (c) to conserve archaeological sites, (d) to conserve Aboriginal objects and Aboriginal places of heritage significance. 1. Sub-clause 5.10(4) of LEP 2012 requires the consent authority to consider the effect of the proposal on the heritage significance of the Killarney Estate HCA before granting consent under cl 5.10. 2. Clause 6.6 of LEP 2012 Landscape areas applies to land in the R2 zone and requires 25% of the site to be landscaped. Clause 6.6 has the following objectives: (a) to have the landscape and townscape area character of Mosman's residential areas maintained and enhanced by requiring landscaping of sites in conjunction with other development, (b) to have a general visual dominance of landscape over buildings maintained, particularly on harbour foreshores, while recognising the difficulty of achieving this on small lots where there are existing buildings such as semi-detached dwellings, (c) to have adequate and usable ground level open space for recreation, landscaping and containing urban run-off. 1. The Mosman Residential Development Control Plan 2012 (DCP 2012) applies to the site at section 1.3. 2. The relevant objectives and planning controls for siting and scale, at section 4.2 of DCP 2012, is: "O2. To have a scale of development which is not excessive and is consistent with the existing or desired future townscape area character. O6. To have adequate side setbacks to provide spatial relief between buildings, encourage view sharing, and minimise overshadowing of neighbouring properties. P8. Development must have a minimum side boundary setback of: (a) single storey (or less than 3.6m wall height): 900mm. (b) two storey (or up to 7.2m wall height): 1.5m. (c) three storey (or over 7.2m wall height): 3m. (d) four storeys (or up to 11m wall height): 4m. P9. Upper storey additions must be set back from the side boundary to comply with the above." 1. The relevant objective and planning control for streetscape and building design, at section 5.1 of DCP 2012, is: "O1.To have development of a scale and appearance which is in keeping with the street and desired future townscape area character. P5. First floor additions should be well integrated into the development design to avoid a bulk/scale relationship that would dominate the existing building, neighbouring buildings or the street." 1. The relevant objective and planning controls for semi-detached dwellings, at section 5.4 of DCP 2012, are: "O1. To have the concept of the semi-detached dwelling as one of a pair or group of dwellings retained, maintaining traditional scale, character and established streetscape values. P1. Any alteration to an individual semi should recognise it as being one of a pair or group of similar, identical or complementary buildings. In this regard, any extension should be carefully integrated with the building to which it is attached, both in its present form and on the assumption that the adjoining owner may wish to undertake extensions in the future. P2. Applicants should demonstrate how the adjoining semi-detached dwelling could be treated to maintain character. O2. To have alterations and additions to a semidetached dwelling which are appropriate to the established scale and building envelope of the original building and to the predominant development in the vicinity. Roof form: P4. The style, pitch, material, profile and colour of the proposed roof should match, complement and extend the existing roof form of the building. P6. Flat roofed areas should only be contemplated where they are not seen from the street or other important viewing positions in the vicinity of the building. Uncharacteristic roof forms and details will not be considered appropriate if they impinge on the street character of the adjoining or nearby semis." 1. The statement of significance for the Killarney Estate HCA at Part 7 of DCP 2012 is: "The Killarney Estate Conservation Area is one of the most interesting conservation areas in Mosman, which, because of the modest scale and the first-glance ordinariness of the street, can be easily overlooked. The compelling aesthetic interest lies in the several different, repetitive designs of small houses that can be seen. The historical significance of the area lies first in the architectural and townscape unity which was furthered by rapid development following the 1910 subdivision and sale of the 'Killarney' land, and secondly in the fact that Dalton Street was Mosman's first to be formed in concrete." 1. The planning controls for the Killarney Estate HCA include the following: "Building form and design: (a) Maintain the predominant small scale low rise building form of the late 19th and early 20th century dwelling houses and semis and their architectural details. (b) Encourage ground level single storey additions to the rear of buildings. (c) Avoid additions and alterations to the façades which disrupt or compromise the repetitive architectural elements and designs of small houses which contribute to the area's heritage significance." Public submissions 1. The adjoining owners on either side of the site gave evidence onsite during the site view. The Court and the parties' representatives and experts viewed the site from the upper storey and rear deck of the dwelling to the east of the site. 2. The neighbours adjoining the site to the east are concerned that there is too much accommodation within the upper storey addition, resulting in a proposal of excessive bulk and scale; a proposal without an upper storey setback compared to the eastern side façade below, and a proposal that unreasonably impacts on their district views and amenity. 3. The neighbour adjoining the site to the west is supportive of the application because she is intending to renovate her dwelling in the future. Expert evidence 1. The applicant relied on the expert evidence of Lisa Wrightson (planning) and James Phillips (heritage). 2. The Council relied on the expert evidence of Steven Layman (planning) and Samantha Polkinghorne (heritage). 3. The planning experts prepared a joint report (Ex 4) and gave oral evidence. The heritage experts prepared a joint report (Ex 5) and gave oral evidence. Contravention of the FSR development standard 1. The planning experts agreed that the proposal has a gross floor area (GFA) of 150.9m2 (FSR of 0.6:1). The FSR development standard for the site is 0.5:1 (126.7m2). 2. The applicant provided a written request seeking to justify the contravention of the FSR development standard (Ex B, tab 3B, ff 274-282). 3. Clause 4.6(4) of LEP 2012 establishes preconditions that must be satisfied before a consent authority, or the Court exercising the functions of the consent authority can exercise the power to grant development consent (Initial Action Pty Ltd v Woollahra Municipal Council (2018) 236 LGERA 256; [2018] NSWLEC 118 at [13] ('Initial Action')). The consent authority must form two positive opinions of satisfaction under cl 4.6(4)(a). As these preconditions are expressed in terms of the opinion or satisfaction of a decision-maker, they are a "jurisdictional fact of a special kind", because the formation of the opinion of satisfaction enlivens the power of the consent authority to grant development consent (Initial Action at [14]). The consent authority, or the Court on appeal, must be satisfied that the applicant's written request has adequately addressed the matters required to be addressed by cl 4.6(3), and that the proposal development will be in the public interest because it is consistent with the objectives of the contravened development standard and the zone, at cl 4.6(4), as follows: (4) Development consent must not be granted for development that contravenes a development standard unless: (a) the consent authority is satisfied that: (i) the applicant's written request has adequately addressed the matters required to be demonstrated by subclause (3), and (ii) the proposed development will be in the public interest because it is consistent with the objectives of the particular standard and the objectives for development within the zone in which the development is proposed to be carried out, and (b) the concurrence of the Secretary has been obtained. 1. On appeal, the Court has the power under cl 4.6(2) of LEP 2012 to grant consent to development that contravenes a development standard without obtaining or assuming the concurrence of the Secretary of the Department of Planning and Environment, pursuant to s 39(6) LEC Act, but should still consider the matters in cl 4.6(5) of LEP 2012 (Initial Action at [29]). The applicant's written request to contravene the FSR development standard 1. The first opinion of satisfaction required by cl 4.6(4)(a)(i) is that the applicant's written request seeking to justify the contravention of a development standard has adequately addressed the matters required to be demonstrated by cl 4.6(3) (see Initial Action at [15]), as follows: (a) that compliance with the development standard is unreasonable or unnecessary in the circumstances of the case, and (b) that there are sufficient environmental planning grounds to justify contravening the development standard 1. The applicant bears the onus to demonstrate that the matters in cl 4.6(3) have been adequately addressed by the written request in order to enable the Court, exercising the functions of the consent authority, to form the requisite opinion of satisfaction (Initial Action at [25]). The consent authority has to be satisfied that the applicant's written request has in fact demonstrated those matters required to be demonstrated by cl 4.6(3), and not simply that the applicant has addressed those matters (RebelMH Neutral Bay Pty Ltd v North Sydney Council [2019] NSWCA 130 at [4]). 2. The common ways in which an applicant might demonstrate that compliance with a development standard is unreasonable or unnecessary are summarised by Preston CJ in Wehbe v Pittwater Council (2007) 156 LGERA 446; [2007] NSWLEC 827 at [42]-[51] ('Wehbe') and repeated in Initial Action [17]-[21]: - "the objectives of the development standard are achieved notwithstanding non-compliance with the standard; - the underlying objective or purpose of the development standard is not relevant to the development, so that compliance is unnecessary; - the underlying objective or purpose would be defeated or thwarted if compliance was required, so that compliance is unreasonable; - the development standard has been abandoned by the council; - the zoning of the site was unreasonable or inappropriate so that the development standard was also unreasonable or unnecessary (note this is a limited way of establishing that compliance is not necessary as it is not a way to effect general planning changes as an alternative to strategic planning powers)." 1. The five ways to demonstrate compliance is unreasonable/unnecessary are not exhaustive, and it may be sufficient to establish only one way (Initial Action at [22]). 2. The applicant submitted that the written request demonstrates that compliance with the FSR development standard is unreasonable or unnecessary because the objectives of the development standard are achieved notwithstanding non-compliance with the standard; and the FSR development standard has been abandoned by the Council. 3. I do not accept that the objectives of the R2 zone are achieved notwithstanding the non-compliance with the FSR development standard, because the proposal is not of a scale that seeks to achieve the desired future character. The term desired future character is not defined by LEP 2012. 4. As the properties, including the site, on either side of Dalton Road form the Killarney Estate HCA, the desired future character of Dalton Road is the preservation of the heritage values identified by the statement of significance for the Killarney Estate HCA (Woollahra Municipal Council v SJD DB2 Pty Ltd [2020] NSWLEC 115 ('SJD DB2') at [50]), because the Killarney Estate HCA is identified as a heritage conservation area by LEP 2012 and the meaning of "desired future character" is to be derived from the text and context of the provisions of LEP 2012 (SJD DB2 at [52]). One of the aims of LEP 2012 includes to recognise, protect and enhance the heritage qualities of the scenic areas of Mosman, and an objective of cl 5.10 of LEP 2012 is to conserve the environmental heritage of Mosman. 5. I accept the applicant's submission that the desired future character of the neighbourhood includes the existing development in Dalton Road (SJD DB2 at [54]). 6. For the reasons set out below, I am not satisfied that the proposal is of a scale that seeks to achieve the desired future character, because the roof form of the upper level addition does not maintain the modest scale of the group of semi-detached dwellings identified as being part of the heritage significance of the Killarney Estate HCA. 7. The written request includes a list of 10 addresses, each with a FSR value and a date (Ex B, f 279), as evidence that the FSR development standard has been virtually abandoned or destroyed by the Council's own actions in granting consents departing from the standard and hence compliance with the standard is unnecessary and unreasonable (Wehbe at [47]). The exceedance of a development standard by development approved under the same standard, should not be interpreted as an abandonment of the controls for a locality without very careful consideration. Development standards are frequently generic because they reflect the zoning of land and do not, or cannot, account for the individual constraints and opportunities of a site. Providing an appropriate degree of flexibility in applying certain development standards to a particular development is not evidence of the Council's abandonment of a development standard. I accept the Council's submission that the information provided is wholly insufficient to establish that the Council has abandoned the FSR development standard in LEP 2012. All but two of the consents listed pre-date the commencement of LEP 2012 and no details are provided of the circumstances or assessment of the applications. Environmental planning grounds 1. The applicant's written request justifies the contravention of the FSR development standard on the bases that compliance is unreasonable or unnecessary for the following reasons (Ex B, f 281): "The bulk of the building is appropriate for the site being smaller or consistent with its surrounds, with the additional floor area located at the rear of the dwelling behind the original existing roof form fronting Dalton Road. It is compliant with regard to impact on solar access and privacy of neighbouring sites. It is compatible with the site and neighbouring buildings. There is no unreasonable impact for neighbours or for the street frontage, with the additional floor area typical of dwellings in Dalton Road and its immediate surrounds." 1. The grounds relied on by the applicant in the written request under cl 4.6 must be "environmental planning grounds" by their nature, and environmental planning grounds is a phrase of wide generality (Four2Five Pty Ltd v Ashfield Council [2015] NSWLEC 90 at [26]) as they refer to grounds that relate to the subject matter, scope and purpose of the EPA Act, including the objects of the Act (Initial Action at [23]). The environmental planning grounds relied upon must be sufficient to justify contravening the development standard and the focus is on the aspect of the development that contravenes the development standard, not the development as a whole (Initial Action at [24]). Therefore, the environmental planning grounds advanced in the written request must justify the contravention of the development standard and not simply promote the benefits of carrying out the development as a whole (Initial Action at [24]). 2. I am not satisfied that the environmental grounds cited by the written request actually justify the contravention of the FSR development standard. The bulk of the first floor addition and its configuration is not compatible with the modest scale of the attached dwellings. The building envelope of the proposal has been driven by the architectural brief, including maintaining the ground floor level of the existing dwelling at the rear despite the fall of the site, which results in the bulk of the proposal being located in the first floor addition. 3. I am not satisfied, pursuant to cl 4.6(4)(a)(i), that the applicant's written request has adequately addressed the matters required to be demonstrated by cl 4.6(3) of LEP 2012. Contravention of the wall height development standard 1. Clause 4.3A of LEP 2012 applies to the proposal because the clause applies to all land in a residential zone to which a maximum building height of 8.5m applies as shown on the Height of Buildings Map, pursuant to subcl (1). 2. The applicant submitted that the proposal does not exceed the wall height development standard under cl 4.3A of LEP 2012 of 7.2m. The Council submitted that the wall height development standard is exceeded. The parties' disagreement focused on the interpretation of the definition of wall height under cl 4.3A of LEP 2012, as follows: wall height means the vertical distance between the ground level (existing) and the underside of the eaves at the wall line, parapet or flat roof, whichever is the highest. 1. Ground level (existing) is a defined term in the dictionary to LEP 2012, as follows: ground level (existing) means the existing level of a site at any point. 1. The applicant submitted that the definition requires the wall height to be measured vertically from the ground level (existing), to the underside of the eave in a different location to the vertical position being measured, when the wall being measured does not terminate at the underside of an eave. The applicant submitted that there is no parapet and there is no flat roof, so the top of the wall has to be measured as "the underside of the eave". Therefore, the wall height of the proposed vertical extension of the portion of the party wall on the site, at its greatest height, is measured from the agreed ground level (existing) of RL 77.04 shown on the survey, to a proposed eave elsewhere on the site. The applicant submitted that this interpretation of the definition results in a proposal that does not exceed the wall height development standard under cl 4.3A of LEP 2012. 2. The Council submitted that the definition wall height requires wall height to be measured vertically from the ground level (existing), to the top of the wall directly above ground level (existing). If the top of the wall does not terminate at the underside of an eave, then the top of the wall, according to Mr Layman, using the Council's interpretation and the RLs on the survey and plans, the height of the proposed raised wall above the party wall is 8.26m. 3. I accept the Council's interpretation of the definition of wall height in cl 4.3A of LEP 2012, for the following reasons: * The definition of wall height under cl 4.3A of LEP 2012 requires the wall height to be measured as a vertical distance from the ground level (existing), as defined in the dictionary, to the top of the wall, which is one of three alternatives: the underside of the eaves at the wall line, or the parapet, or the flat roof. The wall height is to be measured to whichever of the alternatives is the highest. * The term, "vertical distance" in the definition precludes the applicant's approach of using the RL of the underside of an eave elsewhere on the site, which is not vertically above the RL of ground level (existing) of the wall being measured. * A parapet wall is a wall that conceals the edge of the roof behind the wall. A parapet may extend above the roof to conceal the roof behind with a box gutter inside the parapet wall where the roof sheds water towards the parapet wall, or the roof may be joined to the parapet wall as a skillion or flat roof, either at the top or below the top of the parapet wall, where the water is shed away from the parapet wall and flashing is used to make the joint waterproof. * A parapet wall is an alternative to an eave, as an eave is the underside of the roof that overhangs a wall. * The proposed vertical extension of the portion of the party wall on the site ("the vertical extension of the party wall") forms part of the proposed building envelope, in other words, the vertical extension of the wall is an external wall shown on the western elevation. The vertical extension of the party wall is a parapet wall. * The vertical extension of the party wall is aligned with the western boundary, so that the skillion or flat roof (see Sections AA and BB, DA 22) is joined to the top of the parapet wall and falls to the east, to shed water only on the site. 1. The wall height of the vertical extension of the party wall shown in Section BB (DA 22) is the vertical distance between ground level (existing) and the top of the parapet wall. The ground level (existing) is RL 77.04, as shown on Sections BB (DA 22) and DD (DA 24) as the lower red dotted line denoting the underside of the existing slab. The parapet wall is RL 85.62 (Section DD DA 24). The wall height in the location of the proposed garage, of the extension of the party wall, is 8.58m. The wall height exceeds 7.2m. 2. "Development standards" is a defined term under s 1.4 of the EPA Act. It was uncontroversial in the appeal that the requirement under cl 4.3A(4) of LEP 2012, that building on land to which cl 4.3A applies must not have a wall height, at any point of the building (other than at a chimney, gable end or dormer window) that exceeds 7.2 metres, is a development standard. 3. The applicant has not provided a cl 4.6 written request for the contravention of the wall height development standard. Clause 4.6(4) of LEP 2012 establishes preconditions that must be satisfied before a consent authority can exercise the power to grant development consent (Initial Action at [13]). The proposal has an unacceptable impact on the heritage significance of the Killarney Estate HCA 1. The proposed roof form to accommodate the first floor addition adds considerable volume to the form of the roof which overwhelms the modest scale of the existing pair of attached dwellings. 2. The applicant compared the proposal to the first floor addition of the semi-detached dwelling at 17 Dalton Road (Ex F), to demonstrate that the GFA of the first floor addition of 17 Dalton Road is similar to the GFA of the first floor addition of the proposal. Comparing the GFA of the two however, is an exercise that is focused on the two dimensions of a floor plan. The fundamental difference between the two is the volume available to create the three dimensional form of the roof addition between the finished floor level (FFL) of the first floor, and the ridge height over the party wall. At 17 Dalton Road, the FFL of the first floor is RL 83.51, and the original roof ridge over the party wall is RL 87.0, so that the volume of the roof addition could be accommodated within the 3.49m between the two levels, using added converse gables over the first floor accommodation. At 19 Dalton Road, the FFL of the first floor is RL 82.51 and the roof ridge is RL 85.12, so that the volume of the roof addition, if located no higher than the roof ridge, has to be accommodated within the 2.61m between the two levels. 3. Both properties at 17 and 19 Dalton Road have a similar width; 17 Dalton Road is 6.815m at Dalton Road and 19 Dalton Road is 6.86m, however, the vertical distance between the FFL level of the first floor and the original ridge over the party wall is lower at 19 Dalton Road, when compared to 17 Dalton Road, mainly because the pitched roof at the front is over the narrower portion of the building which provides a generous side setback for the side entry to the dwelling. At 17 Dalton Road, the building footprint is wider with a narrow side setback because the entry to the dwelling is at the front, resulting in a greater volume of roof between the FFL of the first floor and the ridge. For this reason, comparing the GFA of the first floor of the proposal to the GFA of the first floor of 17 Dalton Road is not helpful. The real constraint at 19 Dalton Road for the design of the roof over a first floor addition is the short vertical height between the FFL of the first floor and the existing ridge over the party wall. 4. The proposal responds to the constraint of the short vertical height between the FFL of the first floor and the existing ridge over the party wall by raising the party wall by 500mm for a significant length of the party wall, and by incorporating an area of flat roof in order to maintain the FFL and ceiling height of the existing ground floor in the rear addition. 5. I accept the agreement of the planning experts that part of the proposal is three storeys (Ex 4, par 3.9). The proposal does not include adequate side setbacks to provide spatial relief between buildings for the three storey portion of the building. The bulk of the proposed first floor roof form is exacerbated when viewed from Dalton Road by the extension of the proposed converse gables to align with the eastern-most façade of the existing dwelling, despite the first floor eastern elevation being setback from the façades below, beneath the gable. 6. I accept and prefer Mr Layman's evidence that the form of the first floor additions does not satisfactorily integrate with the existing semi-detached dwelling (Ex 4, par 3.4). I do not accept Ms Wrightson's view that the "alterations and additions have been designed so that they appear to be integrated into the roof area" (Ex 4, par 3.9) and for the reasons given in relation to the constraint of the existing roof form, it is impossible to do so if the rear addition matches the existing FFL of the ground floor, even if the floor area of the first floor addition is reduced. 7. The proposal is inconsistent with the objective and relevant planning controls for semi-detached dwellings under Part 5 of DCP 2012. The proposal does not maintain the traditional scale or character of the existing pair of attached dwellings, instead the form of the roof addition overwhelms the scale and character of the existing building. The proposal is not carefully integrated with the existing building, particularly the raising of the party wall by 500mm for a significant length of the party wall, which is contrary to the symmetry and form of the existing roof. The proposed roof form is uncharacteristic and intrusive to the established street character. I am not satisfied that the proposal is of a scale and appearance which is in keeping with the group of modest semi-detached houses in Dalton Road. A more skilful design would better integrate additional accommodation into a rear addition without overwhelming the existing modest dwelling when viewed from Dalton Road. 8. I accept and prefer Ms Polkinghorne's evidence that the proposal raises the "party wall well above the original ridge line creating an unsympathetic interface with 21 Dalton Road", and that the proposal interrupts "the rhythm of the pitched roof lines of the single storey (to Dalton Road) dwellings… [which] makes the new roof more visually prominent" (Ex 5, pp 6 and 9). 9. I have considered the effect of the proposal on the heritage values identified by the statement of significance for the Killarney Estate HCA, and I am not satisfied that the proposal conserves the contribution made by the existing semi-detached dwelling to the collective heritage significance of the Killarney Estate HCA. The proposal does not maintain the predominant small scale low rise building form of the group of semi-detached dwellings and it would disrupt and compromise the repetitive architectural roof forms which contribute to the area's heritage significance. Orders 1. The orders of the Court are: 1. The appeal is dismissed. 2. Development Application No. 8.2020.122.1 for alterations and additions to an existing dwelling at 19 Dalton Road, Mosman, is refused. 3. The exhibits, other than Exhibit 1, are returned. ____________ Susan O'Neill Commissioner of the Court ********** DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 25 January 2022