Tom Gibson and Hannah Constantine, Associate Directors at Haworth Tompkins, reflect on the growing role of mass timber in contemporary architecture. Drawing on projects ranging from performing arts buildings to higher education spaces, they explore the technical challenges and the opportunities timber construction presents for creating buildings that are safe, sustainable and rich in architectural character. 

As architects working across a wide range of sectors from performing arts to large-scale residential and light industrial, we have been pleased to see the use of mass timber grow significantly over the past decade on projects of varying scale, typology and geography. What began as a relatively niche structural approach has steadily matured into a viable alternative to more conventional structural systems. 

Our early mass timber projects often adopted hybrid structures, combining engineered timber with steel and concrete. This was partly for practical reasons, such as reducing structural weight and embodied carbon, but also because we were interested in exploring the qualitative characteristics of solid timber construction. The warmth of exposed timber, the tactile quality of natural materials and the way timber surfaces age and develop a patina over time all contribute to a distinctive architectural atmosphere. 

Over time our technical understanding and confidence in designing with mass timber has grown. Our work on the American Repertory Theater at Harvard University illustrates this evolution. On the drawing board since 2017 and now approaching completion, the project features a superstructure built almost entirely from Black Spruce CLT and glulam sourced from Northern Quebec. Delivering a large performing arts building using mass timber presented  technical challenges, including knowledge of forestry provenance, fire engineering, acoustic isolation, construction sequencing, building insurance and long-term maintenance. 

Ironically, the project team was able to exploit an outdated ‘heavy timber Type IV’ code classification, originally developed for solid wood agricultural barns in New England to streamline technical compliance for this relatively new form of engineered timber construction. In effect, we had to look to the past in order to move forward! Working with a supportive client, an experienced design team and bringing the mass timber subcontractor into the process early as a design-assist partner, helped us navigate complex regulatory frameworks and technical challenges. Over the past year it has been rewarding to see the structural frame steadily take shape on site. 

Closer to home, the Backstage building at The Old Vic in London demonstrates how mass timber can be applied in dense and culturally sensitive, urban contexts. The building uses a European spruce glulam frame and solid timber floors designed not only for low embodied carbon and future disassembly but also to support an advanced fire strategy. By combining compartmentalisation, selective exposure of timber elements, and careful calculation of char rates, the team achieved compliance with rigorous fire regulations while preserving the material’s natural warmth. Mass timber supports multifunctional spaces from rehearsal studios to community areas demonstrating the material’s versatility and its ability to combine structural performance, safety, and user experience. 

Completed in 2025, our project for Pembroke College, Cambridge provides additional teaching, living and cultural spaces within both new and existing buildings. Mass timber is used in a more interwoven and contextually sensitive way that sits comfortably alongside the historic fabric of the college. The centrepiece is a new foyer space with an expressed structural frame in European oak glulam with CLT decks, complemented by solid oak linings and joinery. Together these natural materials, combined with soft diffuse daylight, create a calm and tactile interior environment. 

There is growing scientific evidence suggesting that environments incorporating natural materials such as timber can support wellbeing, encourage social interaction and foster improved learning outcomes. These qualities move beyond the purely quantitative environmental benefits of timber such as its low embodied carbon to highlight its broader contribution to the character and experience of buildings. As a studio, we continue to explore the opportunities and potential of mass timber to deliver buildings that are simultaneously safe, sustainable, and inspiring.