Pouring concrete

This blog is not an authoritative interpretation of the law; it is intended as a general guide.

In this blog, Icon Surveyor’s will consider what ‘Special Foundations are and why and when they are used.

What are ‘Special Foundations’?

In simple terms, section 20 of the Party Wall etc. Act 1996, describes ‘Special Foundations’ as, “foundations in which an assemblage of beams or rods is employed for the purpose of distributing any load.” In addition, section 7(4) of the Act prohibits any building owner from placing ‘special foundations’ on an adjoining owners land without first obtaining the adjoining owners written consent. This is because ‘special foundations’ interfere with the adjoining owners land.

There seems to be some controversy as to what ‘Special Foundations’ actually are. Many surveyors are of the opinion that the use of reinforced concrete or, reinforced concrete underpinning for a basement, is definitively classified as a ‘Special Foundation’. Others are of the opinion that the section 20 of the Act’s description is more prone to be definitive of its predecessor the, London Building Act 1939, in which the same provision was described, by the committee members that formulated the Act, as Grillage Foundation. These are usually used to bare heavy loads such as steel stanchions in weak soil and are described as a special footing that is isolated in an assemblage of beams or rods.

However, the discrepancies were discussed in the case of Chaturachinda v Fairholme (23 September 2015, unreported), and though not binding, His Honour Judge Baily gives a reasoned decision as to the interpretation of what ‘Special Foundations’ mean within the Party Wall Act. There were three important points made by the Court, the first was that a “reinforced concrete block should not be viewed as a single entity, but rather as separate elements of the building; (2)consequently the mass concrete block, properly viewed, constitutes the “foundation” for the purposes of the Act; and (3)there are therefore no special foundations utilised in this design.” In addition, the judge concluded that a “load must be distributed to the ground on the adjoining owners land via the “assemblage of rods or beams otherwise than through a mass concrete block fulfilling the definition of “foundation” under section 20; it is not sufficient to show that some load is distributed from the reinforced concrete below the adjoining owner’s side of the wall to the ground direct(but not necessarily on the adjoining owner’s land).”

The judge went on to point out that the use of any mass concrete to intentionally avoid the restrictions of section 7(4) of the Act, may give the Court reason to consider such use as an active manipulations that in reality is no more than a sham. In other words, building owners should not try to circumvent their legal obligation to obtain an adjoining owner’s written consent prior to commencement of the works because the materials and design of the case upon which HHJ Baily presided were not considered as ‘Special Foundations’.

Icon Surveyors are of the view that the design of ‘Special Foundations’ or a ‘Grillage Foundation’ is a precarious mission and should therefore, always be reviewed, agreed and signed off by a structural engineer. In our experience, a building owner’s expenditure pre-works is beneficial in terms of any subsequent delays and/or hefty costs that are as a result of failing to obtain an expert’s opinion.

Icon Surveyors are happy to provide a free consultation to any building or adjoining owners who may be affected by the subject matter raised in this blog.

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Icon Surveyors

We are a team of party wall surveying experts based throughout London and the surrounding areas. Here, we share informative property survey blogs created by industry experts.



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