Since sustainability in construction has become a major headline, the use of timber composite structures has grown in popularity. Apart from the lower carbon and energy footprint, the high (tensile) strength over density of timber compared to concrete (and even mild steel) is regarded as one of the driving factors for the increase in popularity of the timber and timber composite structures which can be easily assembled, altered, or dismantled with minimum number of trades on the construction site, less noise, and interruption to the surrounding environment. The use of timber beams/joists or plates in conjunction with reinforced concrete (RC) slabs, or so-called timber concrete composite (TCC) floors/decks, has also grown rapidly in the past few decades. Replacing reinforced concrete or steel beams with timber beams/joists, considerably reduce the self-weight, energy- and carbon- footprint of the structure that in turn has contributed to popularity of the timber and timber composite structures. Considering all advantages of timber composite floors, a large body of research has been devoted to structural behaviour of the timber composite floors subjected to sagging moment. But less attention has been paid to behaviour of timber composite floors subjected to hogging moment. The structural behaviour of timber precast concrete composite (TCC) beam to column subassemblies subjected to hogging bending moments was investigated by full-scale laboratory testing, analytical and numerical modelling. Push-out and push-down tests were performed on timber precast concrete composite joints and beams with coach (lag) screw shear connectors embedded in the small grout pockets, respectively. The laboratory tests were used to establish and discuss the influence of size and type of timber beams (i.e., laminated veneer lumber (LVL) or glued laminated timber (GLT)), size of screw shear connectors and amount of reinforcement in the slabs on the failure modes, load-displacement, stiffness, load carrying capacity and ductility of the TCC beam to column connections under hogging bending moments. An analytical model for estimating the peak load and stiffness of the TCC beams under hogging bending moment was proposed by modifying the -method to account for the effect of concrete cracking in a simplified manner. The analytical model was validated against the experimental results. Full scale timber-timber composite (TTC) beam to column subassemblies were fabricated and subjected to push-down loads to assess structural performance of the TTC floors subjected to hogging moment. A total of thirty-one TTC and six bare timber beam-to-column subassemblies (including fourteen replicates) were fabricated and tested to failure subject to hogging bending moment. The TTC beams were fabricated by connecting the cross laminated timber (CLT) slab to the top edge of a pair of laminated veneer lumber (LVL) or glued laminated timber (GLT) beams/joists. The effect of the CLT slab thickness, width, and orientation (i.e., loaded lengthwise or crosswise), column penetration in the CLT slab, bending moment over shear force ratio (span length), degree of shear interaction between the slabs and beams (controlled by size of shear connectors) and type of beams (LVL or GLT) on the structural performance of the TTC subassemblies were investigated experimentally. Moreover, an analytical model for the composite Timoshenko beams was adopted and modified to predict the stiffness and load carrying capacity of the TTC beams under hogging moment. Lastly, finite element (FE) models of the TCC and TTC subassemblies were built and analysed using ABAQUS software. The results of FE simulations were compared with the experimental results to validate and demonstrate the accuracy of the FE models for predicting stiffness, load carrying capacity and failure mode of the TCC and TTC beam to column subassemblies subjected to hogging moment. It was shown that FE models can accurately capture complex modes of failure in TTC and TCC beams subjected to hogging moments. The validated FE models were utilised to conduct a parametric study and assess effect of reinforcing proportion and level of composite action on the stiffness and load carrying capacity of the TCC and TTC beam to column connections.