FIRST FLOOR EXTENSION

(Image taken from one of our projects though the extension is not ours... in fact, it seems to have been stopped) Can you build an extension to a first floor apartment in London? The answer is: occasionally, but the process is significantly more complex than that of a standard house.

If you are considering building upward or outward, there are major structural, legal, and planning hurdles to navigate. Such works involve intensive structural modifications, rigorous fire and acoustic separation detailing, and mandatory Building Control sign-off. Unlike houses, apartments and maisonettes do not benefit from Permitted Development rights; therefore, formal planning permission from your local council is always required.

The Impact of Conservation and Article 4 Directives

In London, many large family homes have been converted into apartments over the decades. These historical conversions have altered the appearance of our streets, leading to stricter regulations.

If your property is situated within a Conservation Area, you must apply for planning permission regardless of the scale of the work. Many boroughs also apply Article 4 Directives, which further restrict changes to the building’s envelope. In these sensitive contexts, your design must demonstrate that it preserves or enhances the character of the streetscape.

The Role of Ownership: Leasehold vs. Freehold

Beyond the planning department, your ability to extend depends heavily on the legal structure of your ownership.

1. Leaseholders

As a leaseholder, you typically own the interior of your apartment, but you do not own the roof, the facade, the structure, or the land. It is a common misconception, often reinforced by estate agents, that a flat roof outside a window is a private terrace or a potential development site. In most cases, it is not.

Most leases require prior written consent from the freeholder before any modifications are executed. This is known as a Licence to Alter. To grant this, a freeholder will typically require:

• Full Planning Permission granted by the local authority.

• Building Control approval and technical drawings.

• Structural Engineering reports.

A freeholder may refuse consent if the proposal risks the structural integrity of the building, impacts the "quiet enjoyment" of other residents, or negatively affects the long-term value of the property.

2. Share of Freehold

If you hold a share of the freehold, you own the building collectively with the other residents. To proceed with an extension, you must obtain the formal agreement of all co-freeholders. This requires a high level of transparency and clear architectural communication to reassure your neighbours that the works will be managed professionally.

3. Sole Freeholders

If you are the sole freeholder of the entire building, you generally do not require third-party consent to extend, provided you meet planning and building regulation requirements. However, if you are a landlord renting out the other units, you remain bound by a duty of care and specific contractual obligations toward your tenants.

Navigating the Licensing Process

A Licence to Alter is a legal safeguard for the building. It ensures that any intervention meets the highest architectural and safety standards. At our studio, we assist clients by providing the technical documentation necessary to reassure freeholders and planning officers alike.

Are you considering an extension to your London apartment? Our team can help you assess the feasibility of your project and guide you through the complex planning and licensing requirements.