Appeal 6005260

The appeal is dismissed.

The main issues are: • whether the proposed annex would result in overdevelopment of the appeal site and, related to this, the adequacy of the remaining garden space; and • the effect on an Ash tree in a neighbouring garden.

The appeal property is a two storey terraced dwelling in a residential road of similar properties located in the [address] Conservation Area. The surrounding area is residential in character.

Policy LP17 of the West Suffolk Local Plan 2024-2041 (2025) says that proposals for residential annexes within the curtilage of an existing dwelling will be permitted where, amongst other criteria, it is ancillary to and subservient in size and scale to the host dwelling and respects the design of the existing dwelling, and the character and appearance of the immediate and surrounding area without creating an independent and/or separate planning unit; and the proposal will not result in inadequate garden, functional or amenity space.

The proposed annex building would replace the existing summerhouse and additionally infill the rearmost part of the garden, directly next to the rear boundary and the adjacent garage block. For a detached, ancillary building in this setting the annex would have a not insignificant footprint, but it would have a limited profile due to its low height and flat roof. For these reasons, together with the degree of separation from the host dwelling, it would not appear disproportionate in size in relation to No 50 or other surrounding built forms.

The modestly-sized terraced dwellings in this part of the street benefit from relatively generous rear gardens. I note that reference is not made to guidance on the size of garden this type of property would normally be expected to provide. [name] 50 has been extended to the rear, the extent of garden remaining with the proposed annex in place would not be so limited in terms of its size and shape that it would harmfully compromise its everyday use and continued enjoyment.

I am mindful of the statutory requirement that that in exercising planning functions in conservation areas special attention shall be paid to the desirability of preserving or enhancing the character or appearance of that area1. For the reasons already given, I consider that the proposal would preserve the character and appearance of the [address] Conservation Area

Therefore, for these reasons, I conclude that the proposed annex would not result in overdevelopment of the appeal site and that adequate garden space would remain following its construction. Consequently, there is no conflict in this regard with Policy LP17 of the West Suffolk Local Plan, as described.

A mature Ash tree is located on the other side of No 50’s rear boundary, sufficiently close to the position of the proposed annex that the whole building would be sited within the tree’s root protection area (RPA). Despite evidence of pollarding, the tree makes a positive contribution to the amenity of the area, reflecting the verdant character of gardens in this part of the conservation area.

Policy LP12 of the Local Plan, concerning trees, requires the retention of trees affected by development, unless it can be demonstrated that removal cannot be avoided and appropriate mitigation or compensation can be achieved. The policy also requires that all planning applications, where there are existing trees on or within the influence of a development site, must include details and a methodology for tree protection from the commencement of development to completion; to ensure that trees are not damaged by construction work.

An arboricultural report includes recommendations for the removal of the existing concrete sub-base, installation of specialist piled foundations, a raised beam construction and approaches to identify root location and minimize incursion into the RPA.

The appellant proposes a condition to require works to be carried out in accordance with the arboricultural assessment and recommendations. Additionally, the condition includes measures to address circumstances where the approved pile positions become untenable due to significant tree roots being encountered during construction.

[name] accept that the proposed condition would address the approach to the building’s foundations and base, I note that the submitted drawings show a shower room with shower, sink and toilet, as well as a kitchenette next to this. These 1 Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990. 2 facilities would be positioned directly next to the location of the tree. The arboricultural report says that new service routes are not available, but that underground service runs within the RPA must be addressed by hand digging, air spading or trenchless technology.

At present, therefore, it is unclear how any water supply, sewage and waste water disposal or electricity supply would be provided to the building and the implications of this for the trees’ root in close proximity to its location. In the absence of further details of the extent of any necessary works to provide services to the building, it is not possible to find that there is sufficient evidence to demonstrate that the tree’s protection will be successfully secured, as required by Policy LP12. Given this uncertainty and lack of any information about service provision, it would not be appropriate to address this matter through a planning condition.

Therefore, for these reasons, I must conclude that it has not been demonstrated that the proposed annex would not have a materially harmful effect on the Ash tree. As such, the proposal is contrary to Policy LP12 of the West Suffolk Local Plan, as described.

I have had regard to the representations made by interested parties. These do not, however, raise any additional matters in relation to the main issues that would lead me to reach a different overall conclusion.

I note the appellant’s comments concerning pre-application engagement with the Council. However, I have considered the submitted proposal on its merits and, therefore, this matter does not have a direct bearing on the appeal decision.

For the reasons given with regard to the second main issue, the appeal should not succeed.