Layout and the existing house
Compare the proposed footprint with circulation, existing openings and the rooms that remain. A larger room is useful only if the whole ground floor works well.
Highbury · N5 · House Extensions
House
extensions
in Highbury, N5
Updated 14 July 2026
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Independent surveying by our sister practice, Hampstead Chartered Surveyors (RICS Firm No. 923064)Plan a Highbury kitchen, dining or garden-room extension around the back of the house as it stands, the garden you want to keep and the limits any conservation guideline sets on height, width and side additions. Bring your plans, photographs of the rear and garden, and a list of what the extra space must do to a conversation with Hampstead Renovations.
Planning-led consent strategy
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Highbury extension specialists
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£10M insurance
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Independent surveying via Hampstead Chartered Surveyors
A considered approach to house extensions in Highbury
Start a house extension with the change you want to make to daily life: a better kitchen and dining arrangement, a practical utility space or a stronger connection to the garden. Compare that goal with the original house, earlier additions and the space that should remain outside.
A useful brief connects room layout with daylight, neighbour relationships, structure, drainage and access. It should explain which work is included, which decisions are still open and which investigations or approvals are needed before construction.
Planning a house extension in Highbury
Each Highbury conservation guideline sets its own limits on rear and side additions, and several allow side extensions only at the properties they list. Read the guideline for the street and the planning history of the house before fixing a footprint.
The standard rear-extension rule
Highbury Fields guidance does not normally permit full-width rear extensions above one storey, or half-width ones above two, unless shown to cause no harm; Aberdeen Park follows that rule, and Calabria Road does not normally allow rear extensions above one storey at garden level.
Side extensions only where scheduled
The Highbury Fields guidelines consider single-storey side extensions only at Schedule 5.6 properties. Highbury New Park limits them to the house numbers its guidelines list, at one storey and at least 2 m behind the front corner; Calabria Road does not normally allow them.
Resolve the whole space before specifying the finish
Structure and drainage
Identify load-bearing alterations, likely foundation investigations and existing drains before fixing the layout. Specify the necessary design work for the actual site rather than assuming a standard foundation solution.
Garden and neighbours
Consider retained outdoor space, trees, levels, overlooking and neighbouring windows together. Include the consequences of glazing and rooflights in the design discussion.
Envelope and internal finishes
Coordinate the roof, walls, glazing, insulation and ventilation with kitchen, utility and joinery choices. Keep allowances and exclusions clear so quotations describe comparable work.
From the initial brief to a coordinated project
Define the brief and constraints
Record the full address, existing layout, prior alterations and intended use. Establish ownership, planning history, local controls and any relevant private agreements.
Develop and test the design
Compare options for the footprint, openings and garden connection. Resolve the necessary structural, drainage and building-control design with the approval route.
Plan construction around the home
Agree deliveries, storage, temporary protection and access to essential facilities. Base sequencing and programme on the actual scope and site arrangements.
Inspect, review and document
Agree required inspections and how design changes will be recorded. Keep the relevant approvals, installation information and completion documentation with the property records.
What to bring to your first conversation
- The address, existing plans and photographs of the rear, side, garden and neighbouring relationship.
- The intended room use, priorities for retained outdoor space and any known drainage or tree constraints.
- Available planning history, ownership or lease documents, access arrangements and occupation requirements.
Include the joinery in the design brief
Discuss fitted storage, wardrobes, shelving and cabinetry alongside the room dimensions, doors, heating and sockets. Historic fabric and fire-resisting elements need their own specification and approval checks.
Explore bespoke joineryHouse extensions: practical questions
Does every house extension require a planning application?
No. Some qualify for permitted development, but eligibility depends on the building, proposal and restrictions. Conservation-area rules treat side and multi-storey rear extensions differently from some single-storey rear work. Flats do not have Part 1 householder rights.
Is planning permission the same as Building Regulations approval?
No. Building Regulations cover construction and extension work, while planning addresses whether development is acceptable. The project may need both, alongside any separate listed-building, lease or private consent.
Will Party Wall procedures apply?
They may apply to work on a party structure, boundary building or qualifying excavation near a neighbour’s foundations. Assess the proposed work rather than assuming every extension needs an award. Minor drilling for shelves or cabinets is a different matter.
Can work to a listed house be treated like an ordinary extension?
The effect on its special architectural or historic interest must be assessed. Listed-building consent can be relevant to internal alterations as well as the addition, and should be considered before significant fabric is changed.
Can a Poets Road terrace have a side-return infill?
The October 2025 management plan expects rear extensions and side-return infills to be single storey and rules out new terraces or balconies at first floor or above. Householder permitted development excludes side extensions in a conservation area, so check how the infill would be classed and allow for a planning application.
Which Aberdeen Park houses can have a side extension?
Only the numbers listed in the Aberdeen Park guidelines, and then only as a rebuilt single-storey side extension. Rear extensions follow the standard rule, and because the road is private, agree access for deliveries, skips and storage with those responsible for it before construction is planned.
For examples of our wider renovation work, browse the portfolio. Discuss which details are relevant to your proposed project when you enquire.
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