Additional Storeys and The Party Wall Act: A Guide

Are you considering adding additional storeys to your property without planning consent? The recent amendment to the General Permitted Development Order allows property owners to do just that. However, before you start envisioning London's skyline...

Diagram of terraced houses from above

Are you considering adding additional storeys to your property without planning consent? The recent amendment to the General Permitted Development Order allows property owners to do just that. However, before you start envisioning London's skyline transforming with these extensions, there are some important considerations to keep in mind.

Eligibility and Implications

The amendment specifies that only properties constructed between 1948 and 2018 are eligible for this extension. This means that most houses in London are excluded. However, if you live in a modern property and meet the other conditions, it could be worth exploring this option. Let's take a closer look at the party wall implications.

Raising the Party Wall

If your property is semi-detached or terraced, the extension will involve raising the party wall(s). However, there is a height limitation - the party walls can only be raised to a maximum height of 3.5m above the adjoining property or any other property in the terrace. This effectively limits the extension to a single storey.

Raising a party wall is a right outlined in section 2(2)(a) of the Party Wall Act. However, it is subject to serving a Party Structure Notice on any affected neighbors.

Resolving Disputes

Upon receiving a notice, the adjoining owner has the option to either consent to the extension, completing the procedures, or dissent, which triggers a dispute. In case of a dispute, both parties must appoint a surveyor. It is also possible for the parties to agree on a single surveyor. The surveyor(s) will then produce a party wall award, which resolves the dispute and authorizes the work. This award ensures that the risk of damage is limited, and the adjoining owner does not suffer unnecessary inconvenience.

Rights and Access

As the party wall is raised, there is a right of access over the adjoining owner's land. However, this right is subject to providing a written 14-day notice. The party wall award, if issued, will specify the conditions relating to access and how the adjoining owner's property should be protected.

Considerations for Converted Properties

If the adjoining property is converted into flats, the raising of the party wall only needs to be notified to the adjoining freeholder. However, associated works, such as cutting pockets into or projections away from the party wall, will also need to be notified to the leaseholder(s) whose demise encompasses the affected section of the party wall.

Future Extensions and Materials

Adjoining owners have the right to enclose upon the raised party walls in the future for similar extensions. However, they are required to pay a due proportion of the construction costs as outlined in section 11(11) of the Act. Typically, this amounts to 50% of the costs, based on the rates applicable at the time of use.

When it comes to the materials used for raising a party wall, the Act does not provide specific guidance. However, Permitted Development limitations require the materials to have a similar appearance to those used in the construction of the current house's exterior. Surveyors generally authorize raising a wall in its original material to avoid potentially prejudicing the adjoining owner's future rights.

A Consideration for Homeowners

While it's unlikely that we'll witness a sudden building boom with modern houses undergoing extensive upward extensions, it could be a viable option for homeowners in need of a home office or additional space. However, it's important to consider the party wall implications and adhere to the regulations outlined in the Party Wall Act.

Adams+Collingwood entry to the NLA New Ideas for Housing competition Adams+Collingwood entry to the NLA New Ideas for Housing competition

If you require advice on raising party walls or any other aspect of party wall procedures, feel free to contact us at 020 7183 2578 or via email. Our team is here to provide you with free advice and guidance.

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