The work explores, experimentally and theoretically, the possibility of producing a novel cladding sandwich panel comprised of a low-density wood fibres (WF) core, made with GUTEX®, and timber engineering board faces. A short discussion of the possibility of using thermal treated timber at the outer face is also made. Tests on small specimens, using physical and optical devices, were performed for the basic mechanical characterization of WF. Shear modulus G was the main target; and values for a range of nominal densities from ρ = 110 to 190 kg/m3 were obtained. Short term load tests on real scale WF sandwich (WFS) specimens of 3.2m span were also per-formed. An initial simple analytical structural model, based on Annex B of Eurocode-5 (CEN-1995, 2003) was used, taking into account the shear deformation of the core. The results show that WFS´s are a viable solution at least for claddings. The line of work is especially attractive as WF is a natural and sustainable product. This research has being carried out with financial support from the European Community within the Sixth Framework Program (NMP2-CT-2005-IP 011799-2).