part twelve

Innovative Construction Techniques and the ‘Strategy for Sustainable Construction’

The Government’s proposed Strategy makes reference to Modern Methods of Construction, or more specifically “Offsite Innovative Construction Techniques” (ICT), as one of the ways to respond to the sustainability imperative.

ICT embraces a range of technologies and processes, involving various forms of supply chain specifications, prefabrication and offsite assembly.

ICT also encompasses a range of terms, such as; ‘Modular Constructions’, ‘Volumetric Construction’, ‘Light Steel Framing’, et al, with one term often being confused with another.

‘Modular Construction’ is a term often used for the factory production of pre-engineered building units that are delivered to site and assembled as large ‘Volumetric Components’, or as substantial elements of a building.

The modular units may form complete rooms, parts of rooms, or separate highly serviced units such as; toilets, plant rooms, pipework ‘cassettes’, lifts, etc, and may be either completely finished or needing further work on site.

So, ‘Volumetric Construction’ – also often referred to as ‘Modular Construction’ – involves the production of three-dimensional units in controlled factory conditions, prior to transportation to site.

The maximum size of a volumetric unit is only really determined/limited by the practicalities of transportation, road and site access, and installation planning.

The strength and rigidity of the modules are, however, very important considerations and the design and construction must be such that the modules can be first securely transported and then safely craned into place on-site without being damaged.

Some would differentiate between ‘Modular’ and ‘Volumetric’ by, for example, calling a pre-cast concrete staircase unit ‘modular’ and a pre-engineered plant room ‘volumetric’, but those differentiations are sometimes confusing and not particularly helpful.

The reason why the ICT agenda is advocated in the ‘Strategy for Sustainable Construction’ is that the Government’s Task Force for preparing the Strategy believes that: “Greater use of offsite construction techniques gives measured benefits and improvements”.

These “benefits and improvements” include:-

• More effective use of materials, including the reduction of waste and its disposal;

• Cost and time predictability, leading to improved overall project timetables;

• Improved productivity, performance and quality in a controlled environment, with less defects and operating uncertainty;

• High standards of design quality, promoted by the need to plan really well ‘up front’ for guaranteed success on-site;

• Improved environmental performance of the final product, for example because of reduced transportation requirements;

• Better management of available and often scarce resources, not least labour and materials;

• Improved health and safety performance, both in the factory and on-site;

• Flexibility: Changes to internal layouts can be easily achieved using offsite techniques;

• Integration of services: Savings in space allocated to services;

• Productivity: Substantial improvement in overall task productivity. Fostering of team working and manufacturing ethos;

• Dimensional Accuracy: Computerised detailing and manufacture improves tolerances and ensures dimensional accuracy of elements and assemblies.