Application number: 18/P1649     Ward: Village

Officer Recommendation: GRANT Planning Permission subject to conditions and the views of the Council’s Flood Risk Manager and Historic England (Archaeology) 

Proposal: Erection of a single storey rear extension; alterations to existing first floor balcony and balustrade; replacement of existing rear dormer window with two dormer windows together with associated internal alterations and construction of basement beneath part of rear garden.

The Committee noted the officer’s report and presentation and information in the Supplementary Agenda. The Planning Team Leader drew Members’ attention to the Flood Risk Officer comments in the Supplementary Agenda. The Planning Team Leader also informed the Committee that Historic England had commented and had recommended an archaeological protection condition that would become Condition 19.

The Committee received verbal representations from two Objectors, from the applicant’s Agent and from Ward Councillor Andrew Howard.

The Objectors made points including:

·         Neighbours do not object to some development on this site, as they have extended their own homes

·         But this proposal is huge and out of scale with the house, creating 4000 ft² underground

·         The proposed extension is 6m in depth and rises above ground floor level

·         If allowed it would be the biggest underground development in Wimbledon

·         The proposal would affect trees in the Conservation Area

·         The proposal would not meet the requirements of Merton policy DMD2 and is greater than 50% of the area of the garden

·         The new extension should not be considered as part of the garden

·         There is a lack of detail and accuracy in some of the information provided

·         Don’t want to stop neighbours from extending but the size of this basement is unprecedented and almost commercial

·         Neighbours are worried about flood risk given the local hydrology

·         This is a massive excavation that may cause instability in the area

·         There is the potential for noise in the Conservation Area from the air conditioning units that will be required by the basement

·         There is a risk to the mature trees in neighbours gardens from the excavations.

The Applicant’s Agent made points including:

·         The House is a listed building, apart from the removal of the contemporary garage non of the proposed development would be seen from the street

·         The proposal is similar to other recently approved schemes in the area

·         The Council’s tree officer does not believe the development will cause harm

·         The Council’s Design and Conservation Officer has no problems with the proposal

·         The Council’s Engineers have approved the proposals

·         We do fully understand the concerns of neighbours but Merton Council safeguards are stringent and this development meets them all

·         In light of neighbours concerns the basement size has been reduced and is now well under 43% of the garden

·         Other neighbours have built large extensions and basements, this application is not unusual in Wimbledon

The Ward Councillor Andrew Howard made points including:

·         I represent both the applicant and objectors

·         What is needed is a clear determination

·         Both sides have made articulate representations

·         Concerned about very recent amendments, is a deferral for more time required?

Officers explained that as the recent amendment was to reduce the length of the basement it was thought that a re-consultation was not necessary.

Members were concerned that figures were not shown on the Plans and asked officers what the actual percentage of the garden area was equal to the Basement. Officers replied that they did not know why figures were not available. They calculated that the percentage coverage was 44%. The Committee noted that the agent to the application said that this figure was less than 43%, whereas objectors thought it as greater than 50%.

Officers confirmed that the dimensions of the  proposed swimming pool were 25m long by  4.1m wide. The depth of the basement is 4m deep with the pool being a further 1.4 m deep.

Officers confirmed that the Tree Officer had requested that root protection areas be included and assessments be undertaken, and that she  was content that these measures would ensure that no trees were harmed by the excavation. Only one mature tree was to be lost to the development Officers said that they expected to see trees planted within the new landscaping.

Members noted that conditions had been included to mitigate and monitor noise and vibration to neighbouring properties during construction. Officers did not believe that conditions could be added to require monitoring of ground movement after construction was complete. It was the Officers view was that a Party Wall agreement would cover this aspect.

Officers replied to Members questions about the construction of the basement saying that the Council Engineers had considered this and were satisfied. Officers explained how a pump system would be used to allow water in and then pump it out.

Members were concerned regarding the Flood Risk Officers’ comments, contained in the Supplementary Agenda. They noted that the  Flood Risk Officer says that there is a slight concern that due to the significant size of the basement there is very limited ‘natural’ ground left in which surface water may infiltrate.  Officers replied to this by saying that there would be no development until the applicant had submitted the further details required by the Flood Risk Engineer, this was required by condition.

Members asked what would happen If problems were encountered with the basement construction once works had begun. Officers replied that they had not experienced this with any other basement constructions

Members made comments including:

·         It is a relatively large development and thank you to Officers for putting stringent controls on the development. The  Council’s experts all agree that the development will not cause problems

·         The proposal is vast, it may affect neighbours housing and it is overdevelopment

·         It is one large development too many for the area

·         Think that there should be a condition on long term monitoring in neighbours houses

·         The development is not fair on neighbours and is unneighbourly

·         Extension seems bigger than single storey, not convinced by the drawings and concerned that they are not to scale

The Committee voted on the motion to approve the application but this was lost, and the application was thus refused.

Officers asked Members to provide their reasons for refusal. Some Members disagreed whether or not  this was necessary, but Members gave Officers reasons for refusal subject to the usual resolution that the exact wording was delegated to the Director of Environment and Regeneration. Officers requested that the Chair and Vice-Chair should be asked to approve the final version of the reasons for refusal

RESOLVED

The Committee agreed to:

1.            REFUSE Planning Permission for the following reasons:

·         The size of the proposed basement is disproportionate to the size of the house

·         The proposal represents overdevelopment in a Conservation Area

·         The size of the proposed basement too large and is unneighbourly.

2.            DELEGATE to the Director of Environment & Regeneration the authority to make any appropriate amendments in the context of the above to the wording of the grounds of refusal including references to appropriate policies