Some UK housing developers discontinuing CLT for high-rise after post-Grenfell legislation

Swan is the latest housing developer to join the list of developers evaluating concrete and steel alternative for residential units over 18 metres.

Despite a successful completion of the mid-rise, six-storey Watts Grove development Tower Hamlets in East London, a 65-unit residential project, Swan will now restrict the use of CLT to two- and three-storey residential housing.

A statement released by Swan stated that “Swan will continue to use Cross Laminated Timber for our offsite manufacturing production in residential construction under 18m as we still believe that CLT is one of the best products to utilise in residential construction. The reasons we chose to use CLT initially (design flexibility, environmental sustainability, energy efficiency, fire and acoustic performance) still apply. We have a further 700 homes planned for manufacture utilising CLT and these will continue to be precision engineered in our innovative factory in Basildon creating local jobs and investing in UK manufacturing.”

“We also have a significant future pipeline of development, including major projects in Purfleet and Southend-on-Sea, where these homes include buildings over 18m high and, so for these, we are exploring a steel framed alternative approach to ensure we can continue to benefit from offsite construction to improve quality, decrease construction times and create sustainable homes.”

In November 2018, the UK government banned combustible materials on the external walls of any new buildings taller than 18 metres.  They were also banned in renovations of existing buildings.

The legislation limited the use of materials to those with a European fire rating of Class A1 or A2, and stated explicitly that wood products do not fall under this classification.

While engineered timber, particularly cross-laminated timber (CLT), is increasingly being championed in architecture as a sustainable alternative to steel and concrete structural frameworks, its use has been limited by the legislation.