In this work, the mechanical and dielectric properties of a novel centresymmetric honeycomb structure (SILICOMB) are evaluated using finite element (FE) and finite difference time domain (FDTD) models as well as experimental results. The numerical analysis of the in-plane mechanical properties has been carried out on the full scale and on the representative volume element (RVE) model. The FE model results are compared with the outcome of a series of experimental compressive tests carried out on core structures manufactured using fused deposition modelling (FDM) technique. The comparison with the set of results highlights the specific deformation mechanism of the repetitive cell geometry. Full-wave FDTD analysis as well as quasi-electrostatic calculations have been run to investigate in-plane dielectric properties. Electromagnetic simulations, over a wide frequency band, allow the characterisation of the SILICOMB structure by two effective permittivity functions. Effective permittivity functions are frequency, polarisation and geometry dependent. Multiple geometry parameters to be used to design the honeycomb configurations for multifunctional applications are thus identified and discussed in the paper.