'Special' Foundations' what makes you so 'Special'?
The Party Wall etc Act 1996 provides rights for building owners to undertake activities that would otherwise be regarded as trespass. For example, the building owner may have the right to underpin a party wall, which would involve excavating for and installing concrete below the party wall and over the boundary line within the land of the adjoining owner. If, in the future the adjoining owner wishes to undertake a basement conversion, they may have to remove part of the newly installed underpin by cutting or breaking out the mass concrete where this projects on their side.
If you have ever been unfortunate enough to have had to break up a reinforced concrete slab with a hand-held breaker (as I have), you will know that it is incredible strong, and resistant to impact, considerably stronger that plain concrete without reinforcement. If the building owner had installed reinforced concrete foundations, it would be extremely difficult for the adjoining owner to excavate for their basement without significant breaking out or cutting.
The Party Wall etc Act 1996 Section 20 differentiates reinforced concrete foundations by the term ‘special foundations’ for this reason, they are excluded from rights under the Act by Section 7 (4). It is not possible under the Act to install reinforced concrete foundations on the land of the adjoining owner without express written consent, and even if express consent is given, the adjoining owners right to make a claim against the building owner for breaking out can extend for perpetuity under Section 11 (10).
The matter of special foundations is further complicated by recent developments in case law relating to basements. We recommend that any project that involves such foundations are evaluated with a professional party wall surveyor to understand the implications of such designs on the project development and party wall process.
Whilst writing I make reference to the etching included in this post. I am very happy to present such etchings from books left to me by my grandfather, books that he used in the 1940's when he was undertaking his technical training as a surveyor. It is a pleasure to share these with readers.