The objective of this work was to investigate the selected properties of particleboard (PB) containing waste rubber – a mixture of carpets and isolators (GWR) and tires (GWT) from discarded automobiles. Mechanical (tensile strength (IB), bending strength (BS), physical (water absorption (WA), thickness swelling (TS) after 2 and 24 h of immersion), chemical (volatile compounds - VOC using GC-MS method), thermo-physical (thermal conductivity and diffusivity, specific heat capacity) and sound absorption coefficient were analyzed. In addition, a density profile and microscopic analysis of the particleboards were performed. The addition of 10% rubber to the PB either maintains the IB or improves the BS of the composite. The best results for WA after 24 h (97.94%) and TS after 24 h (30.74%) were achieved for composites containing tire granulates. For this reason, these PBs are the most suitable for utilization in areas with higher humidity. Adding 20% of GWR to PB decreased the total content of VOC emissions by 85% so it can be stated that the rubber probably acts as a VOC sorbent. Control PBs had significantly lower thermal conductivity and diffusivity, and comparable specific heat capacity values than PBs containing GWR and GWT. The best sound insulation properties were obtained for PBs containing 20% of GWR. Microscopic analysis pointed to greater GWT and GWR contents resulting in higher C content in the PB. All PBs containing GWR have a higher mean density compared to that of control, ranging from 597 kg·m−3 to 615 kg·m−3. On the other hand, PB containing GWT had comparable or lower density values.