Timber-Concrete Composite (TCC) is a technology which focuses on optimizing performance and material requirements by engineering a structural connection between timber and concrete components. Structural efficiency is gained by creating composite action between the two materials. This hybridization enables designers to increase spans, reduce deflections, improve vibration performance and streamline structures in pursuit of sustainable architecture and cost efficiency.
As with other panelized products we have taken a comprehensive approach which encourages the integration of electrical, mechanical and acoustic systems into structural panels with architecturally exposed timber and concrete. These panels reduce the proportion of the carbon-intensive concrete components by allowing timber to carry the load.
Timber-concrete composite panels are typically used in a floor or roof application, but can also be used as wall panels. Either mass timber panels (e.g. CLT or DLT) or beams can be used, and the timber-to-concrete shear connection can be made in a variety of ways, including headed screws or other mechanical fasteners.
Precast vs On-site Pour
The concrete slab can be poured on-site or precast in a shop environment. On-site pours are generally preferred as they create a structural diaphragm without requiring additional topping or post-fix connections between panels. Pouring the concrete on-site also reduces the weight of the prefab timber panels, making shipping more efficient and erection faster.
Mass Timber Panels vs Timber Members
Either solid mass timber panels (e.g. CLT or DLT) or spaced engineered wood beams/columns (e.g. Glulam, PSL, LVL) can be used as the support for the concrete topping. The choice between the two systems is generally based on architectural intent or considerations of MEP distribution.
Composite Connector Choice
There are many options here including custom connectors. One common option is to use diagonally inclined screws half-drilled into the timber elements, left protruding into the concrete topping, creating the composite action. There are also many proprietary connectors available, including perforated metal connectors.
Our TCC Fabrication Process
We fabricate or procure the mass timber panels required, mill any end conditions or openings and install the composite connectors. If precast panels are desired, we pour the concrete in our shop to achieve factory quality. If the concrete is site-poured, this is typically handled by others.