Construction disputes involving technical complexities can benefit from ADR approaches.

The Technology and Construction Court recently handed down judgment in MJS Projects (March) Ltd v RPS Consulting Services Ltd [2025] EWHC 831 (TCC), a case addressing design liability in construction projects. The judgment, delivered on 9 April 2025, provides important insight to the responsibilities of design consultants and contractors in design and build arrangements.

Key issues in dispute

The case concerned the design and construction of a container park near Felixstowe Port. MJS Projects (March) Limited (MJS), a regional building contractor operating in East Anglia, was engaged as the main contractor under a JCT Design and Build contract. MJS subsequently subcontracted the design responsibilities to RPS Consulting Services Limited (RPS).

The work was completed in August 2017, but by December 2017, the concrete surrounding three Gatic slot drains in the container yard showed significant deterioration, including settlement, cracking and damage. MJS Projects claimed the damage resulted from RPS’s negligent design, while RPS argued defective construction was to blame.

The central dispute concerned whether the damage resulted from RPS’s allegedly negligent design or from defective construction. MJS Projects claimed that RPS’s design was inadequate regarding load distribution calculations and dowel specifications.

A critical technical issue involved the dowels connecting the concrete slabs to the drain surrounds. The design specified 32mm dowels, but 25mm dowels were actually installed. Additionally, these dowels were placed incorrectly at approximately 75mm from the surface rather than the specified 200mm depth.

Expert evidence and concurrent causation

The case turned primarily on expert evidence, with both parties agreeing that some of the construction work performed by MJS Construction (a separate entity from the claimant) was negligent, but disagreeing on items including:

• Whether the design properly accounted for dynamic load factors.
• Whether the dowels (as designed) would have been adequate to transfer loads across the concrete joints.
• How loads would transfer across the joint between concrete slabs and drain surrounds.
• Whether a Mass Concrete Taper (MCT) was necessary for the design to work.

A notable aspect of the case was RPS’s pleading that if any damage was caused or contributed to by MJS Construction, this would constitute a concurrent cause of the damage claimed.

The defendant also attempted to introduce new arguments, including an allegation that MJS had failed to supervise the builders, MJS Construction. However, the court accepted the claimant’s submission that this allegation was not sufficiently pleaded in the defence.

Court’s findings

Her Honour Judge Kelly concluded that the damage identified by December 2017 was caused by defective construction, not negligent design. Judge Kelly determined that RPS’s design was neither negligent nor in breach of contract. Even if there had been design errors, the judge found these would not have caused the damage that manifested by December 2017.

Final thoughts

For construction professionals, especially those with design liability, the case underscores the importance of maintaining clear documentation of design decisions and construction processes, as well as ensuring proper supervision of construction work, particularly when design responsibilities have been subcontracted.

Given the technical complexity involved, construction disputes of this nature can benefit from ADR approaches such as expert determination, adjudication, or mediation, which can offer faster, more cost-effective solutions than litigation while preserving business relationships in an industry where such relationships are key.

This article was first published on 6th May 2025 by Construction Law here.