Offsite construction dovetails nicely with the new legislation’s provisions for tall buildings

Modern methods of construction are well suited to the construction of higher-risk buildings under the Building Safety Act 2022 (BSA).

The new legislation

The reforms introduced by the BSA included extended limitation periods for bringing claims where homes are not fit for habitation, strict competency requirements placed on consultants and professionals working on projects, and the establishment of a Building Safety Regulator (BSR) to implement a stricter regulatory regime for higher-risk buildings and to oversee the safety and performance of all buildings.

Much of the detail in the new safety law will be set out in secondary legislation, which is expected to be enacted at some point between April and October 2023. However, parts 3 and 4 of the Building Safety Act set out the general framework of how the higher-risk residential building regime will operate, including the system of gateways:

  • Gateway 1 The parties must provide information to show that fire safety requirements have been considered and incorporated with their planning permission application.
  • Gateway 2 Confirmation is required from the BSR that it is satisfied the building’s design meets the requirements of the Building Regulations 2010 before works start.
  • Gateway 3 Once construction is completed, the BSR carries out a further assessment to confirm whether the work complies with the Building Regulations and that all relevant information has been produced and provided to the “accountable person”.

There are also strict change control requirements on higher-risk buildings, with any changes to the works classed as “major” or “notifiable” requiring further review and approval by the BSR.

The desire to make as few changes as possible during construction is common to both MMC and the BSA higher-risk building regime

The secondary legislation is expected to define “major” changes as changes to the use, structural design or certain fire safety features in the building, and “notifiable” changes as alterations of plans previously approved by the BSR during Gateway 2, or the substitution of products to be used in the works.

Since there are likely to be significant delays of up to 10 working days while approval of changes from the BSR is awaited, parties will want to make very few changes in order to complete the project quickly and efficiently.

Offsite construction

Modern methods such as offsite prefabrication are being encouraged by the UK government and some private sector developers. For large-scale construction, they offer a way to produce housing units relatively quickly through a manufacturing process, and there is also a reduced likelihood of defects arising where the same units are being produced on a large scale (and provided the entire batch is not flawed).

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For MMC to be used effectively on a project, however, the structural design and choice of materials must be fixed at an early stage to allow manufacturing to start – and not to be interrupted. This contrasts with more traditional methods where changes or variations often arise in the design or choice of materials during the course of the project.

Alignment with the new regime

So, how does the BSA higher-risk building regime align with MMC? The desire to make as few changes as possible during the construction phase is common to both the BSA higher-risk building regime and MMC. In MMC and in the envisaged change control regime under the BSA, changes are to a certain extent discouraged as they would be likely to result in higher costs, greater inefficiencies and longer delays than on traditional projects.

For this reason, MMC (whether intentionally or not) lends itself well to the BSA regime if the parties can obtain approval from the BSR before the manufacturing process begins – on the basis that once approval has been received and the process has started, very few changes will be made.

Risks to be aware of

There are potential disadvantages to using MMC, however. One risk is that, because developers are generally required to pay more up front (roughly 60% before the modules reach site) on projects using MMC, adequate payment security is essential.

In addition, offsite manufacture means there is less visibility for the developer’s professional team. Factory inspections are required which need to be frequent enough to gauge that the quality of the products being manufactured is up to scratch, while not being so frequent that they disrupt the modular contractor’s operations.

A final risk is that if the quality of the materials or a batch of products does turn out to be substandard or defective, this will incur significant delays and costs if the materials need to be remanufactured from scratch.

Jamie Olsen Ferreira is a knowledge lawyer and Stacey Cassidy a construction partner at law firm TLT