If custom housing and other “third way” models of delivering new homes are to gain any traction, they will need innovative thinking and innovative construction systems. But in Hammersmith, west London, the success of Rational House suggests the time is right for alternative approaches that bring new diversity to the sector, writes Elaine Knutt.
Rational House is a modular system based on off-site manufactured concrete components, available in a range of dimensions that combine to form highly flexible homes or mixed-use schemes. After the first home (above) was built as a demonstration and sold privately, the London Borough of Hammersmith and Fulham was so impressed that it signed up Rational House as supplier to its new housing company, which will build homes for market sale and discounted market sale.
The system was designed by architect Bob Dalziel, a former director of 3D Reid, and Tim Battle of Rybka Battle. But 18 months ago, realising that the project needed to bridge the gap between concept and market, they invited Davis Langdon on board as project manager for product development. AECOM also became involved in the engineering behind the system, and Willmott Dixon was recruited to advise on supply chain efficiency and building methods.
Rational House isn’t particularly cheap: Ben de Waal, head of residential at Davis Langdon, quotes a build cost including fit-out at £150 per square foot. Instead, the efficiencies and savings lie in the streamlining of planning and pre-construction process and the speed and lack of disruption of the erection. “It’s a high-quality system, although not the cheapest, and built to code level 4 as standard.”
Rational House was hired by Hammersmith via an OJEU tender, which also positions it to work with neighbouring Westminster (where a site is already in negotiation) and Kensington and Chelsea. In addition, de Waal says it has had enquiries from several more London boroughs, Cardiff City Council, and a volume housebuilder interested in building Rational shells then fitting them out to its own spec.
But in a sector that has seen so many demonstration modular systems come and go, what makes Rational House different? “This is about great design, it’s a good urban design that is well-suited to urban infill locations,” says de Waal. “And we built a prototype that people can come and see and that matches the target market [of outright or shared ownership buyers]. If you go up to the BRE, it’s hard to see how the houses there would fit into an urban high-density setting.”
