Streatham Lambeth SW16
Flat extension
Project description | Streatham Lambeth SW16 Flat extension and internal alterations to a ground floor garden flat
Addition of a side and rear extension to create a second bedroom and an enlarged kitchen, dining and living area that opens up to the rear garden.
Architectural services
- Initial home consultation
- Measured survey and production of existing set of drawings
- Planning stage design and submission
- Planning submission and liaising with Lambeth planning officers
- Preparation of technical plans and information for the Building Regulations submission
- Preparation of tendering plans and information for builders to price
Client – Private
Project type – Single storey side / rear extension and internal alterations to a ground floor garden flat
Location – Streatham, Lambeth SW16
Currently – Planning approval, Autumn 2015
Design considerations and Lambeth planning assessment matters
The application site comprises a two-storey mid-terrace building which has been converted into two self-contained flats. The property is located on the western side of Brancaster Road which is a predominantly residential area. The pattern of development within the surrounding area is predominantly Victorian terrace housing with an ‘L’ shaped footprint.
To the front elevation the application property has a two storey bay window topped with a pitched roof form. The property has a recessed entrance with an ornate surround which is mirrored on the adjoining property.
To the rear elevation the property has a three storey rear return, and to the rear is a single storey rear extension.
The property is not situated within a Conservation Area, and is not listed.
Policy Q11 requires building alterations and extensions to deliver good design quality and extensions should be subordinate to the main property. Part (e) of this policy relates to infill extensions and requires that infill extensions should be single storey.
The SPD on Building Alterations and Extensions gives further detailed advice on the design of infill and wrap-around extensions and includes illustrations of what would be acceptable. It states that the extent of rearward projection beyond the gable end of the return is not specified however, subordination will still be required and issues of amenity, prevailing character and retention of sufficient garden space will be important considerations. End extensions and wrap-arounds may be treated in the same material as the main return. To minimise adverse impact, the party wall of any rear extension should be as low as possible. The fascia and gutters should not overhang onto neighbouring property; for this reason parapet walls with parapet gutters are the recommended option.
It is considered that the scale and design of the proposed extension complies with Policy Q11. The proposed extension would be single storey which is two storeys lower than the height of the rear return. The detailing would be simple, with materials to match existing and windows and patio doors installed on its rear elevation wall. The proposed extension would comply with the guidance within the SPD Building Alterations and Extensions (2015) and would be considered sympathetic and visually subordinate to the original building.
Furthermore, the proposals would still retain an acceptable amount of rear garden space as a result of the new extension and would comply with Policy Q14(c)(i) of the Local Plan in this regard.
In light of the above assessment, it is considered that the proposed rear/side extension would comply with the Policies Q2, Q5, Q8, Q11 and Q14 of the Local Plan and the SPD Building Alterations and Extension (2015) and it is therefore acceptable in terms of design.
The proposed extension would result in a 5.9m deep wall on the boundary with number 26. Due to a the modest eaves height and depth of the extension adjacent to the boundary with number 24, the extension would be approximately 2.8m high when viewed from the garden of number 26 which is considered to be acceptable. Furthermore, the eaves height of the extension would be approximately 1.1m higher than the existing boundary fence with number 26 which is approx. 1.8m in height. As such, it is considered that any loss of outlook or increased sense of enclosure associated with the proposed extension would be relatively minor and would not warrant a reason for refusal.
With regards to the property at number 20, the proposed extension would extend to the depth of the existing rear extension on the application site and would retain a simalr eaves and ridge height along this boundary. As such, due its modest height and depth and given that there is an original single storey extension at number 20, it is considered that the proposed extension would not result in an unacceptable impact on the amenity of number 20 Brancaster Road.
Having regard to all of the above it is considered that the application would comply with Policy Q2 of the Local Plan and the SPD Building Alterations and Extension (2015).
CONCLUSION – Upon full assessment of the submitted material supporting the application, it is considered that the objectives of relevant policies of the Council’s Local Plan (2015) have been met. Grant Planning Permission subject to the imposition of conditions.
This project is also featured on our Lambeth residential architects page as an example of a garden-flat extension to a converted Victorian terrace.
For inspiration and ideas see below some of our other residential projects in Lambeth.
HOME DESIGN – Find ideas for your project.
- Side extensions London residential guide
- Rear extensions London residential guide
- Kitchen extensions London residential guide
- Roof extensions London residential guide
- Residential renovations London guide
- Mansard roof extensions London residential guide
- Contemporary extensions London residential guide
- Flat extensions London residential guide
- Garden flat extensions London residential guide
- House extensions London residential guide
ARCHITECTURAL PLANS
We have prepared a guide on the type of Architectural plans you will need for your home project, and a guide specifically for Terraced house extension plans with advice on detached and semi-detached properties.
BOROUGH SPECIFIC ARCHITECT AND PLANNING GUIDES FOR YOUR HOME PROJECT
Your local Council will have in place design and planning requirements for your home project and you will need to obtain planning approval for a wide range of extensions and alterations to your property.
When you get in touch we will offer you detailed advice about what is likely that your Council will approve and in the meantime we have prepared the following architectural and planning guides that include extracts of the relevant planning policy and examples of our projects in our Borough.
Barnet architects | Planning and design homeowner guide, Camden residential architect and planning guide, Enfield residential architect and planning guide, Hackney residential architect and planning guide, Hammersmith Fulham residential architect and planning guide, Haringey architects | Planning and design homeowner guide and planning guide, Islington residential architect and planning guide, Kensington and Chelsea Conservation architects, residential and planning guide, Lambeth residential architect and planning guide, Lewisham residential architect and planning guide, Newham residential architect and planning guide, Tower Hamlets residential architect and planning guide, Waltham Forest residential architect and planning guide, Wandsworth residential architect and planning guide, Westminster residential architect and planning guide
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You will come away with a clear sense of your next steps and greater confidence to make informed decisions. The consultation (2hrs, £250 +VAT) is a standalone service with no obligation to proceed.
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Not sure where to start with your renovation or extension?
Read this before you meet an architect, speak to a builder or spend money on drawings.
This free, architect-prepared guide walks you through the 15 essential questions every homeowner should ask before starting a project.
"Should we renovate, extend… or walk away?
15 Questions every London homeowner must ask before starting a project to include homes in Conservation Areas and Listed Buildings."
Whether you're planning a modest rear extension or major alterations to a listed home, it will help you avoid expensive mistakes and give you clarity on what’s possible for your property. Includes guidance on:
Planning approvals. Conservation areas.
Timelines and costs. Appointments you need to make.
Design and sustainability options.
When to press ahead and when to walk away

We provide architectural services for residential projects in the following London Boroughs:
Barnet, Camden, Enfield, Hackney, Hammersmith and Fulham, Haringey, Islington, Kensington and Chelsea, Lambeth, Lewisham, Newham, Tower Hamlets, Waltham Forest, Wandsworth, Westminster
We specialise in
- Greener homes
- Retrofit and energy efficiency for older and traditional buildings
- Conservation areas
- Listed Buildings
- Homeowner architectural services
- Property developments architectural services

GOAStudio London residential architecture limited.
86-90 Paul Street, EC2A 4NE, Hackney
Chestnut Avenue South, E17 9EJ, Waltham Forest
t: 0203 984 3005
