Six different types of cork-based sandwich panels were produced, using Aleppo pine as the face or inner sheets and a cork (agglomerate or expanded) as the core, with a view to applications in building insulation. The physical properties of these sandwich panels were evaluated by scanning electron microscopy, measurements of density, moisture absorption, and moisture desorption. The thermal conductivity of the sandwich panels was evaluated by three different methods: the guarded-hot-plate, thermal conductivity meter, and heat-flow meter (CTMF) methods. The overall results suggest that eco-friendly cork-based sandwich panels are efficient thermal insulators and may be used to reduce energy consumption in buildings.