Time for a balanced view on modern methods of construction

  • Modern methods of construction (MMC) could play an important role in helping to address Britain’s housing shortage
  • However, from the design stage onwards, MMC presents risks which must be managed
  • Allison Whittington, Head of Housing, Zurich Municipal, discusses the importance of approaching MMC with your eyes wide open

According to the National Housing Federation, we need to build 340,000 new homes each year until 2031 in England alone, if we are to plug the housing gap.

Modern methods of construction (MMC) undoubtedly have an important part to play in helping to create many of these homes. The advantages of using MMC are wide-ranging – shorter and more predictable construction timescales, cheaper materials, less waste, and reduced scope for errors – to name a few.

However, from the design stage through to occupation, MMC can also present risks and challenges.

Designing out risk

All too often, simple design flaws can cause problems that might not immediately be evident.

Installing timber cladding at ground level, for example, makes a building more vulnerable to arson than if the cladding starts at the second floor or higher.
Another problem, which is sometimes found in modular buildings, is that the bathrooms are fitted in a way that if something goes wrong, an entire unit needs to be removed to fix the problem.

Often, these risks can be addressed through intelligent design. However, taking an informed decision on MMC means weighing up the risks that cannot be as easily mitigated, against the potential benefits.

Managing the construction phase

The rise in factory production means entire rooms can sometimes be assembled off-site, in safe, sterile environments. However, the laser precision that these environments offer is lost if the work is not properly supervised, or if the workers themselves don’t have the right skills and training.

Even when a building has been carefully designed and constructed using MMC, there can be challenges you would not expect to find in a traditional brick-and-block build. With a timber-framed property, for example, the risk of fire spreading rapidly can usually be mitigated through compartmentation – dividing the building into compartments using fire-resistant doors, floors or walls. But when a tenant moves in, a simple act such as drilling a hole through a wall can undermine this careful design and create significant fire risk.

And, if firefighters are unsure how a building will respond to a fire – as can be the case with MMC – they will typically use far more water to extinguish it, which could cause additional damage.

We handled a claim following a fire in the top floor of a timber-framed block of flats. The building withstood the fire well, but because of the amount of water used, the apartment where the fire started – and the 19 flats below it – were all completely destroyed.

Keep your eyes wide open

As an insurer, we don’t want to put customers off MMC by saying it is simply too risky. But, we do want our customers to take a balanced view, and consider whether the risks, over the lifecycle of a property, outweigh the benefits. It’s about approaching MMC with your eyes wide open.