Design defects can cause various types of construction damage, of varying severity. The most serious is a miscalculation of the structure, which leads to cracks caused by differential settlement of the foundation and can even lead to the collapse of the house.
A project must take many factors into account: the geotechnical study of the ground, its bearing capacity, the foundation designed, the materials used and the distribution of structural elements.
Claiming for incorrect project design
You should make a claim when there is evidence that the project was incorrectly designed, either because there was no geotechnical report or because its recommendations were ignored, and that, as a consequence, the foundation was inadequate for the land on which the building was constructed, causing settlement and cracks in the dwelling.
Another ground for a claim arises when a house has excessive spans (pillars spaced too far apart), causing excessive stresses in the floor slab, which lead to cracks and uneven floors.
However, anyone who accepts the management of works whose initial project they did not draw up themselves also assumes responsibility for the omissions, deficiencies or imperfections of the project, without prejudice to any right of recourse against the designer, under article 17.7 of the LOE.
Under article 12.3 c) and d), the site architect must resolve any contingencies that arise in the works and record in the Book of Orders and Assistance the precise instructions for the correct interpretation of the project, drawing up any modifications to the project required by the progress of the works, provided they comply with the regulations.
An expert architect will study the project and determine whether the design of the housing project or building was incorrect.
Responsibility for project defects
Those responsible for design defects are the project architect and the site architect and, by extension, their insurers.
Their responsibility is to design and plan the project for the house or building properly, taking into account the ground on which it is to be built and the geotechnical report and its recommendations, and ensuring that the structural calculation is adequate and that no slab deflections occur that would cause uneven floors, cracks, excessive settlement or, of course, the collapse of the building.
Under article 3.1 b) of the Spanish Building Act (LOE), buildings must be designed, constructed, maintained and preserved in such a way that no damage occurs to the building, or parts of it, that originates in or affects the foundation or structural elements.
The project must, of course, comply with the relevant technical and urban planning regulations (articles 10.1 and 10.2 b) of the LOE). In this respect, the technical construction standard par excellence is the Spanish Technical Building Code (CTE), approved by Royal Decree 314/2006 of 17 March.
The CTE requires (in Part I, Annex I) that the construction report of the project include a justification of the characteristics of the soil and the parameters to be considered in calculating the part of the structural system corresponding to the foundation. For the structural system (foundation, supporting structure and horizontal structure), it must “establish the data and the starting hypothesis, the programme of needs, the calculation bases and procedures or methods used for the entire structural system, as well as the characteristics of the materials involved”.
If the architect has failed not only in their task as designer but also in managing the works with regular inspections, they should be held liable for all the responsibilities inherent to their position and professional commission.