This project set out to explore the feasibility of using timber floor slabs in place of reinforced
concrete units. As timber is a natural and renewable building resource, this replacement was
found to bring an economical benefit in construction of multi-storey buildings. Since timber
is much lighter than concrete, the amount of foundation loads in a multi-storey building were
greatly reduced. To be feasible, any structure built this way must adhere to the requirements
of the Building Regulations and the structural design codes (Eurocodes). The most critical
aspects to meeting the requirements were anticipated to be ensuring adequate robustness and
fire resistance.
In this project, the aforementioned requirements were explored and the ability of the hybrid
system to perform was evaluated. The potential environmental benefits were investigated,
and a comparative study was performed to gauge the relative performances of the timber and
concrete systems. The comparative study looked at how the amount of steel required, the
loads to foundations, the cost, and the environmental impact changed when making the
substitution for a range of situations. It was found that in buildings with columns closer than
or equal to 9m apart, and with imposed loads of 3kN/m2 or less, using timber meant a
reduction in the amount of foundation load. The analysis for costs found that using timber
would be a less expensive option, mostly due to the reduced cost of the foundation. The study
into environmental impact suggested that use of timber was more detrimental to the
environment but limitations of the calculation model used were noted.
Finally, with the structural performance of the concept verified, some practical considerations
were addressed, with suggested methods of enhancing robustness and fire resistance.