Agenda item

Demolition and rebuilding of existing dwelling with basement floor and erection of a new two-storey house with basement floor to the front of the site (AMENDED DESCRIPTION).

RECOMMENDATION: Grant planning permission, subject to conditions.

 

The Committee considered a report, previously circulated, on the application for planning permission at 12 Denewood Road, N6. The report set out details of the site and surroundings, images of the site as existing and proposed, details of the proposal, planning history, relevant planning policy, consultation and responses, assessment of the application and human rights and equalities issues and recommended that the application be granted, subject to conditions. The Planning Officer gave a presentation highlighting the key aspects of the report, and circulated two letters received after the circulation of the Committee report, one from Geotechnical and Environmental Associates and one from a neighbouring resident in objection to the application.

 

In response to a question from the Committee, it was confirmed that the application remained unchanged from that deferred from the special Sub-Committee meeting on 30 July.

 

Cllr Rachel Allison addressed the Committee in objection to the application on behalf of local residents and the Highgate Society, and Dr Tom Davidson also spoke in objection. The following points were raised by the objectors:

 

• The proposal represented overdevelopment of the site, as there had never been two houses on the site at the same time.
• Allowing two houses on the site would set a worrying precedent for the area and could lead to a erosion of the character of the Conservation Area.
• This application would involve two large basements, one of double-depth as it would contain a swimming pool; there were recognised problems in the area in respect of the water table, and concern was expressed that this may lead to further problems.
• There was concern that no intrusive assessment of the potential impact of the basement had been undertaken at the site itself.
• Given the existing problems in the area and the size of the proposed basements, the proposal would lead to a significant risk of harm being caused.

 

The Committee questioned the objectors, and the following issues were raised in the course of the questions and responses:

 

·        The objectors recognised that the street was diverse architecturally and so there were no specific concerns in respect of the design of the proposal, but the character of the Conservation Area lay in the overall streetscape, the large gardens and sense of open space and having two houses on this site would have a negative impact on this.

·        There was a strong objection to the principle of having two houses on the site.

·        The Committee asked for information on the criteria on which the area had been designated a Conservation Area in the first place; officers advised that the designation was in 1967 and that there was no existing character appraisal other than that summarised as ‘large houses on large plots’. It was noted that work was currently underway on a character appraisal for the Highgate Conservation Area.

·        Marc Dorfman, Assistant Director, Planning, Regeneration and Economy, advised that the key policies relating to this application were UD3 and UD4 on the impact on amenity and quality of design, and that these would also be taken into consideration in respect of the Conservation Area Consent assessment.

·        It was noted that one of the OS plans of the area appeared to indicate that at one time there had been two houses on the site at the time the Conservation Area was designated.

·        In response to a question from the Committee on whether the location of the existing house had an impact on the application of the policy in respect of backland development, Mr Dorfman advised that this was the case; were the existing house at the front of the plot and permission sought to build at the rear, the recommendation would likely be for refusal.

·        It was suggested that a report on the current status of all Conservation Area appraisals be brought to Regulatory Committee for information.

·        The Committee asked about the inclusion of this particular street in the Conservation Area, which was generally focussed on Highgate Village; officers responded that it was on the basis of generous streets and detached houses with strong landscaping.

·        Officers felt that this site was unique in character and would not establish any precedent for the building of additional houses at the rear of existing sites.

·        It was confirmed that the proposed condition regarding a Construction Management Plan would address the issue of flooding.

·        Dr Davidson felt that, despite the proposed condition which would preclude any work on the site until and unless a full assessment of the flood risks was undertaken and mitigation in place to address these risks, an element of risk still remained and that all necessary assessments should be undertaken before planning permission was granted.

·        Mr Dorfman advised that for future applications, proposals involving basements such as these would require a full basement impact assessment to be submitted prior to the validation of the application, but that it was currently a transition phase while applications were dealt with that had been submitted prior to the new requirements being agreed. Although full information had not been required at validation phase when this application was submitted, the same information would still be required before development could commence, as a condition.

·        Dr Davidson confirmed that he was aware of flooding issues directly opposite this site, at foundation level. Mr Davidson was not aware of a particular instance of a basement development at one property having a negative impact on a neighbouring property, but felt that it was logical that this may be an outcome, given the issues with groundwater in the area.

 

Almas Bavcic, the applicant’s representative, addressed the Committee in support of the application and made the following points:

 

• This site is unique, being 15-20m longer than other sites in the area, with the existing building located to the rear and a historical precedent for there being a house to the front of the site.
• The proposal would restore the original streetscape by replacing a house at the front of the site.
• The building at the front would screen the rear house.
• The rear house was set away from neighbouring properties and there were no nearby basements; water flow would therefore not be affected.
• It was reported that detailed guidance had been sought from professionals in respect of the basement excavations, but that boreholes on site were costly and time-consuming and were therefore usually only undertaken once planning permission had been granted.

 

The Committee asked questions of Mr Bavcic, and the following issues were raised:

 

• The Committee discussed the report provided by GEA, and it was confirmed by Mr Bavcic that this had been commissioned prior to the requirement for basement impact assessments to be produced and had therefore been intended only to inform the design process. The aim had been to identify any potential issues that would affect the developer and neighbouring properties. While the consultants used anticipated that their information was accurate, it was expected that a hydrological condition would be required to be undertaken as a condition of any permission granted.
• In response to a question from the Committee as to whether he was aware of any instances in the area where a basement construction had impacted on a neighbouring property, Mr Bavcic advised that where works were undertaken properly, such issues should not arise.

 

The Committee examined the plans and asked further questions of officers.

 

In discussing potential additional conditions, were the application to be granted it was proposed that a condition be added requiring a site-specific hydrological survey, including on-site borehole testing.

 

The Chair moved the recommendations of the report, with the additional condition in respect of site-specific hydrological testing and on a vote it was:

 

RESOLVED

 

That, with an additional condition requiring site-specific hydrological testing before construction could commence, application HGY/2011/2284 be granted, subject to the following conditions:

 

Drawing No’s: 390-000, 390-010, 390-011, 390-310, 390-311, 390-001, 390-003, 390-004, 390-005, 390-006, 390-300, 390-301, 390-302, 390-303 & 390-304

 

Conditions:

 

IMPLEMENTATION

 

1.The development hereby authorised must be begun not later than the expiration of 3 years from the date of this permission, failing which the permission shall be of no effect.

 

Reason: This condition is imposed by virtue of the provisions of the Planning & Compulsory Purchase Act 2004 and to prevent the accumulation of unimplemented planning permissions.

 

2.The development hereby authorised shall be carried out in complete accordance with the plans and specifications submitted to, and approved in writing by the Local Planning Authority.

 

Reason: In order to ensure the development is carried out in accordance with the approved details and in the interests of amenity

 

MATERIALS & BOUNDARY TREATEMENT

 

3. Notwithstanding the description of the materials in the application, no development shall be commenced until precise details of the materials to be used in connection with the development hereby permitted have been submitted to, approved in writing by and implemented in accordance with the requirements of the Local Planning Authority.

 

Reason: In order to retain control over the external appearance of the development in the interest of the visual amenity of the area.

 

4. Details of a scheme depicting those areas to be treated by means of hard and soft landscaping, including replacement trees, shall be submitted to, approved in writing by, and implemented in accordance with the approved details. Such a scheme shall include a schedule of species and a schedule of proposed materials/ samples to be submitted to, and approved in writing by the Local Planning Authority.

 

Reason: In order to ensure the development has satisfactory landscaped areas in the interests of the visual amenity of the area.

 

5. Before the occupation of the new dwellings hereby permitted details of the boundary treatment to separate the gardens of the two dwellings hereby approved shall be submitted to and approved in writing by the Local Planning Authority.

 

Reason: To ensure satisfactory privacy for future occupiers and to protect the character and setting of the Listed Building.

 

TREE PROTECTION

 

6. All works associated with this development shall be undertaken in accordance with the detail as specified in the Arboricultural Report & Method Statement.

 

Reason: To safeguard the health of existing trees which represent an important amenity feature.

 

7. A pre-commencement site meeting must take place with the Architect, the consulting Arboriculturist, the Local Authority Arboriculturist, the Planning Officer to confirm tree protective measures to be implemented. All protective measures must be installed prior to the commencement of works on site and shall be inspected by the Council Arboriculturist and thereafter be retained in place until the works are complete.

 

Reason: To safeguard the health of existing trees which represent an important amenity feature.

 

PERMITTED DEVELOPMENT RIGHTS

 

8. Notwithstanding the provisions of the Town and Country Planning (General Permitted Development) (Amendment) (England) Order 2008 (or any order revoking and re-enacting that Order with or without modification), no development otherwise permitted by any part of Class A, D & E of Part 1 to Schedule 2 of that Order shall be carried out on site.

 

Reason: To safeguard the amenities of neighbouring occupiers and the general locality.

 

9. No windows other than those shown on the approved drawings shall be inserted in the extensions unless otherwise agreed in writing by the Local Planning Authority.

 

Reason: To safeguard the privacy and amenities of occupiers of adjoining residential properties.

 

CONSTRUCTION

 

10. The construction works of the development hereby granted shall not be carried out before 0800 or after 1800 hours Monday to Friday or before 0800 or after 1300 hours on Saturday and not at all on Sundays or Bank Holidays

 

Reason: In order to ensure that the proposal does not prejudice the enjoyment of neighbouring occupiers of their properties.

 

11. No development shall take place, including any works of demolition, until a Construction Management Plan has been submitted to and approved in writing by the Local Planning Authority.  The approved plan shall include identification of potential impacts of basement developments, methods of mitigation of such impacts and details of ongoing monitoring of the actions being taken.  The approved plans should be adhered to throughout the construction period and shall provide details on:

 

i)                                The phasing programming and timing of the works.

 

ii)                              The steps taken to consider the cumulative impact of existing and additional basement development in the neighbourhood on hydrology.

 

iii)                            Site management and access, including the storage of plant and materials used in constructing the development;

 

iv)                            Details of the excavation and construction of the basement;

 

v)                              Measures to ensure the stability of adjoining properties,

 

vi)                            Vehicle and machinery specifications

 

Reason:  In order to protect the residential amenity and highways safety of the locality.

 

12. The site or contractor company must be registered with the Considerate Constructors Scheme. Proof of registration must be sent to the Local Planning Authority prior to any works being carried out on the site.

 

Reason: In order to ensure that the proposal does not prejudice the enjoyment of neighbouring occupiers of their properties.

 

 

INFORMATIVE: The new development will require numbering. The applicant should contact the Local Charges at least six weeks before the development is occupied (tel. 020 8489 5573) to arrange for the allocation of a suitable address.

 

INFORMATIVE: Thames Water requests that the Applicant should incorporate within their proposal, protection to the property by installing for example, a non-return valve or other suitable device to avoid the risk of backflow at a later date, on the assumption that the sewerage network may surcharge to ground level during storm conditions.

 

Where a developer proposes to discharge groundwater into a public sewer, a groundwater discharge permit will be required. Groundwater discharges typically result from construction site dewatering, deep excavations, basement infiltration, borehole installation, testing and site remediation. Groundwater permit enquiries should be directed to Thames Water’s Risk Management Team by telephoning 020 8507 4890 or by emailing wwqriskmanagement@thameswater.co.uk. Application forms should be completed on line via www.thameswater.co.uk/wastewaterquality. Any discharge made without a permit is deemed illegal and may result in prosecution under the provisions of the Water Industry Act 1991.

 

 

REASONS FOR APPROVAL

 

The position, scale, mass, detail and alignment of the proposed replacement dwelling to the rear of the site and new dwelling to the front of the site have been carefully considered and will complement the other two-storey flat roofed buildings found along the street and will preserve the character and appearance of the conservation area. The positioning of this building provides sufficient gaps between buildings as well as protecting trees and greenery along the side and front boundaries of the site. In addition the proposal will not ]give rise to a significant degree of overlooking or loss of privacy, daylight or sunlight to neighbouring properties. As such the proposal is considered to be in accordance with policies UD3 'General Principles', UD4 'Quality Design', G10 'Conservation', CSV1 'Development in Conservation Areas', OS17 ‘Tree Protection, Tree Masses and Spines' of the adopted Haringey Unitary Development Plan and Supplementary Planning Guidance SPG1a 'Design Guidance and Design Statements', SPG2 'Conservation and Archaeology' and the Council’s ‘Housing’ SPD.

 

 

Section 106: No

 

Please note that the conditions referred to in the minutes are those as originally proposed in the officer's report to the Sub-Committee; any amended wording, additional conditions, deletions or informatives agreed by the Sub-Committee and recorded in the minuted resolution, will, in accordance with the Sub-Committee's decision, be incorporated into the Planning Permission as subsequently issued.