A structural, load-bearing panel useful in constructing multistory buildings may have a panel height, panel width, and panel thickness, and may include a first layer comprising at least 75 wt. % of concrete, relative to a total weight of the first layer; an insulation layer comprising flexible polymer, the insulation layer having a thickness of at least 5 cm; and a second layer comprising at least 75 wt. % concrete, wherein the insulation layer is sandwiched between the first and second layers, and wherein the panel is suitable to be set in any of a planar, curved, and polyhedral cross-sectional shape. Set panels are not flexible, though the flexibility of the insulation layer, particularly of a polyethylene foam, may allow the panel to have a curved, or polyhedral cross-section while still serving as a structural support.