The construction industry is under pressure to cut its carbon footprint, and new research from Zaheer Doomah suggests a practical way forward—one that could reshape how we think about formwork and concrete durability. Doomah’s study, published in *Environmental Science and Sustainable Development* (translated from *Sciences de l’Environnement et Développement Durable*), explores how reusing softwood formwork—traditionally discarded after a single use—could align with circular economy principles while maintaining structural integrity.
The research centers on Grade 35 concrete, a common structural material, and tests how different levels of formwork reuse affect its performance. Doomah and his team cast concrete cubes into four formwork categories: steel (as a control), new pine softwood, once-used pine, and thrice-used pine. The key variable? Workability, adjusted via water-to-cement ratios and the addition of water-reducing admixtures.
The results are promising. Concrete cast in formwork reused up to three times retained its strength and durability—measured through compressive strength, water absorption, and chloride penetration—provided it incorporated a water-reducing admixture. Without it, performance declined. As Doomah notes, “The right mix design isn’t just about strength—it’s about balancing reusability with material behavior. A small admixture can extend formwork life by orders of magnitude.”
For the energy sector, this has commercial implications beyond sustainability. Reducing formwork waste cuts material procurement costs, lowers transport emissions, and streamlines site operations. In a sector where margins are tight and regulatory pressure on emissions is rising, such innovations could offer a competitive edge.
The study doesn’t just validate a material tweak—it points to a systemic shift. If softwood formwork can be reused reliably, the construction industry could significantly reduce its reliance on steel and single-use timber, both of which carry high carbon and resource costs. The next step? Scaling these findings across real-world projects and refining site management practices to minimize waste.
This isn’t about reinventing concrete—it’s about rethinking how we build with it. And in an industry responsible for a third of global emissions, even small changes in formwork reuse could ripple into substantial gains.