Party Wall Special Foundations

Party Wall Special Foundations – In Depth Guide

What are Party Wall Special Foundations and why do they require additional consideration under the Act?

The Party Wall Act requires the express consent in writing of an Adjoining Owner before the underpinning of a party wall using special foundations.

Introduction to Party Wall Special Foundations

The Party Wall etc. Act 1996 is a crucial piece of legislation that governs specific types of building works in the United Kingdom.

One of the aspects of this Act is the provision under section 7(4) of the Act regarding the placing of special foundations on land belonging to an Adjoining Owner. In this article, we explore what special foundations are, their importance, and how they are addressed under the Party Wall etc. Act 1996.

Understanding Party Wall Special Foundations

Party Wall Special foundations refer to foundations that are reinforced, typically with steel rebar. A special foundation is defined within the Act as follows:

“special foundations” means foundations in which an assemblage of beams or rods is employed for the purpose of distributing any load”

These types of foundations are typically used when underpinning party walls, commonly in association with the construction of a new basement.

Special foundations play a vital role in ensuring the stability and safety of structures. They provide a secure base and transfer the load of the building to deeper, more stable layers of soil or rock. Modern special foundations allow underpinning using a slimmer profile than mass concrete which allows developers/owners to gain crucial floor area without jeopardising the support/integrity of the existing structure above.

The Party Wall etc. Act 1996 and Special Foundations

Under the Party Wall etc. Act 1996, the underpinning of a party wall using special foundations require the express consent in writing by an Adjoining Owner. This means that if you intend to carry out building works involving special foundations, you must serve a formal notice to the affected adjoining owners or occupants.

1.) Serving Notice : When special foundations are proposed, the building owner is required to serve a notice to all affected neighbouring properties. The notice should include specific information about the proposed foundation works, such as the depth, size, and type of construction.

2.) Adjoining Owner’s Response : Upon receiving the notice, the adjoining owner has several options. They can either provide their consent to their use, or dissent.

Why should I dissent to the use of special foundations below my property?

Special foundations consent under the Party Wall Act is effectively a hangover from the 1939 London Building Act.

Around this time, an old style of foundation known as ‘Steel Grillage Foundations’ were sometime used in foundation design. These foundations encased an arrangement of large steel beams within concrete that would have been extremely difficult to trim back/remove if placed on the land of an Adjoining Owner, hence the requirement for consent.

Nowadays, modern special foundations are constructed using rebar and allow for much stronger foundations on a slimmer profile. This actually benefits both sides when underpinning a party wall to form a basement. Slimmer underpinning means more floor area in a basement on either side of the wall. Any overspill of concrete can be removed with relative ease. This means there is no real reason in modern times to dispute the use of special foundations.

Why should I consent to the use of special foundations below my property?

As above, special foundations offer a slimmer profile for the underpinning. If you or your successors in title plan on developing your own property including constructing a basement in future, you would benefit from being able to make use of the reinforced concrete underpinning (special foundations) already constructed by your neighbours (subject to an appropriate payment being made for making use).

What if my neighbours do not consent to the use of special foundations?

If your neighbours do not consent to the use of special foundations then there are a few alternative options:

1.) Use mass concrete underpinning instead.

2.) Explore the possibility of constructing a mass concrete rail below the reinforced concrete underpinning/wall with your engineer. This is commonly known as a ‘Bailey Rail’. However this is a somewhat controversial approach following a ruling in the Courts in Chaturachinda V Fairholme 2015.


The Party Wall etc. Act 1996 provides a framework for addressing special foundation works, ensuring that adjoining owners are adequately informed, and their interests are protected. By following the procedures outlined in the Act, building owners can usually proceed with their construction projects while maintaining good relationships with their neighbours and mitigating potential risks.

It is usually recommended by surveyors that special foundations consent is granted. On the occasions that it is not there are alternative options available to enable works to proceed.

Remember, this article post provides general information and should not be considered legal advice. If you require specific guidance regarding Party Wall special foundations or any matters related to the Party Wall etc. Act 1996, please do not hesitate to get in touch.

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Further Guidance when appointing a Party Wall Surveyor

For further help and advice on serving a Party Wall Notice, please get in touch.

As a Building Owner planning work to your property please get in touch for help and advice to manage the Party Wall process.

Alternatively, if you are an Adjoining Owner and have received a notice we can advise on how you can best protect your property.

If you would rather we called you instead, please fill in our Contact form and we will be in touch.

For information on how the Party Wall Act affects you see our Party Wall Fact Sheet.

You can also find further information in our Party Wall FAQs. The FAQs have been compiled from questions we are often asked about the Act.

You can also find guidance on choosing a Party Wall Surveyor in our recent news article. Also see our recent article on serving a Party Wall Excavation Notice.

There is some further information in the government’s explanatory booklet on the Party Wall process.

For a quick online quote for Party Wall advice, send us the details of your project.

Local Party Wall Surveyors

To contact a Party Wall surveyor that’s local to you, see details of our teams in :

For advice direct from one of our Surveyors, please call our Enquiry line on 020 4534 3135.

If you are planning work that is covered by the Act, or if you have received notice of work from a neighbour and want advice on how best to protect your property please contact:

Link: Contact Us

Team members shown:

  • Rickie Bloom
  • Geoffrey Adams
  • Mark Amodio
  • Henry Woodley

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