Precast concrete sandwich panels are commonly used as architectural or structural walls. A typical concrete panel is made of two normal strength concrete wythes and a layer of a rigid insulation sandwiched in between. The purpose of this research is to design and experimentally validate a new generation of precast sandwich panels that are much lighter in weight by using a special ultra-high strength concrete, leading to only 25 mm thick wythes. This will lead to significant savings in shipping, handling and installation costs. Also, a more structurally efficient wall will be developed by introducing a new system that connects the two concrete wythes, enabling them to work together more effectively. For this, noncorrosive basalt and glass fiber ties and studs will be used to connect the wythes together because of their very low thermal conductivity, leading to a more thermally-efficient wall.