What’s special about foundations?

The strength of a building lies in its foundations and it is therefore vital that the foundations are designed carefully and with proper regard for the structure they are to support. This is especially so when excavating a basement, or undertaking works on a party wall or that are in close proximity to a neighbour’s property where, not only do you need to consider your own building but also that of your neighbour.

A foundation is defined in the Party Wall etc Act 1996 (“the Act”) as:

     “the solid ground or artificially formed support resting on solid ground on which the wall rests.” 

Often it may be desirable or more cost efficient to use reinforced concrete foundations, i.e. special foundations. Special foundations are defined in the Act as:

     “foundations in which an assemblage of beams or rods is employed for the purposes of distributing any load.” 

There are often very good reasons to employ special foundations in a development and in some cases, such as basement construction, the use of reinforced concrete is regarded to be the most appropriate method. The use of metal reinforcement adds structural stability and strength to enable a smaller foundation to be achieved thereby maximising the subterranean usable space. It might also avoid unnecessary excavation and additional, avoidable, pouring of concrete, which may be beneficial for the building owner.

However, under section 7(4) of the Act a building owner cannot use special foundations without the adjoining owner’s written consent. The adjoining owner therefore has an effective veto which can creates difficulties for a building owner who has devised his project in a particular way and who would have to alter his plans. It should be noted that the Act requires written consent; oral consent would not be sufficient. 

The rationale for requiring an adjoining owner’s written consent to special foundations is that reinforced foundations are very difficult to alter, require specialist and expensive techniques to remove and might cause the neighbour difficulties if he wished to do work to the party wall in the future. However, the additional strength and structural stability provided by special foundations might actually benefit an adjoining owner who jointly owns the wall in respect of which the special foundations are to be placed. Moreover, the adjoining owner might be less inconvenience during the works given the reduced excavation that would otherwise take place were mass concrete foundations to be used. Therefore, in practice, there may be advantages as well as disadvantages to special foundations.

The Act also contains other provisions regarding special foundations, such as:

1. The ability of the adjoining owner to serve a counter notice under section 4(1)(b) requiring that the foundations be placed at a specified greater depth or strength than that proposed by the building owner. This is to accommodate any future plans that the adjoining owner may have, for instance, if he intends to make use of the special foundations in a future development of his property. The Act does require the adjoining owner to pay for the additional specifications he requires to the special foundations.
2. The obligation under section 11(10) on the building owner to pay to the adjoining owner any increased costs he might incur erecting his own structure as a result of the existence of the special foundations. In other words, the building owner must compensate the adjoining owner if the cost of his works is increased by the special foundations. In order to recover the increased costs, the adjoining owner must ensure that the owner of the building to which the special foundations belong receives an account with invoices and supporting documents within 2 months beginning with the day on which the adjoining owner’s works complete. This is an incredibly short period of time. The Act specifically refers to the building owner receiving the account not simply the adjoining owner providing the account. The Act specifically refers to the owner of the building to which the special foundations belong, which may not necessarily be the person who erected the special foundations if, for instance, he sold the property between the date he completed his works and the date the adjoining owner completed his works. 

Therefore, in order to erect special foundations, a building owner not only needs written consent from the adjoining owner but he is exposed to other risks and potential costs. Moreover, any subsequent buyer of the building owner’s property may be liable for the increased costs the adjoining owner incurs which were caused by special foundations which he did not even place on his land. Prospective purchasers should be mindful when purchasing a property in which special foundations have been used and understand the potential exposure. 

The issue of special foundations was considered by the court in Chaturachinda v Fairholme (2015) which concerned a basement construction. The unusual design there involved underpinning a party wall with reinforced concrete underpins linked to a reinforced concrete slab between the walls of the building owner’s property (thereby creating a reinforced concrete box), which rested on mass concrete. It was the mass concrete, according to the building owner, that formed the foundation and the reinforced underpins were simply a wall. As such, they said that the construction did not involve special foundations and did not require the adjoining owner’s consent. On the other hand, the neighbours claimed that the design was a sham and an impermissible attempt to evade the prohibition on special foundations without consent. They argued that both the reinforced underpin and the mass concrete strip below were the foundation together. They also argued that the reinforced concrete box constituted a foundation because it not only distributed load to the mass concrete strip below the underpins but also to the solid ground on the building owner’s side, namely below the reinforced concrete slab.

The court disagreed with the adjoining owner, finding that the reinforced underpinning was not a special foundation because it was not the foundation. The foundation was the mass concrete strip which was a separate and distinct element of the construction from the reinforced concrete underpin. It did not transfer load to the neighbour’s land. The fact that a load from a higher part of the structure (for instance a reinforced concrete wall above ground) is transmitted through a lower part of the structure does not make the lower part of the structure part of a foundation. The court heard expert evidence and concluded that any load being carried from the reinforced basement slab to the ground were no more than minimal and could be disregarded. 

Therefore, just because a structure includes some reinforcement below ground will not necessarily make it a special foundation. Whether a particular design that includes reinforcement will or will not be a special foundation requiring the adjoining owner’s written consent will be a matter of fact. The court made it clear that it would not turn a blind eye to a device clearly intended to circumvent the rights of an adjoining owner not to have special foundations placed without his written consent, such as in the case of a concrete blinding which serves no real purpose. However, it seems that where mass concrete is an important but distinct part of the construction with a proper purpose, what might otherwise appear to many to be a special foundation, will not be so.

Key Contacts    

If you are considering carrying out building works to your property, or if your neighbour is about to commence works which will affect you and you have been served with a notice under the Party Wall etc Act 1996, our experienced team can help you through all stages of the process. 

For more information about how we can help you in relation to property disputes or for advice on the Party Wall etc Act 1996 please contact John Turner on 020 7462 6029 or Mark Brassey on 020 7462 6027.