The paper aims at examining the thermal and hygrothermal behavior of a multilayer system of outer walls with a foamed low conductivity concrete core, specifically designed in the light of the climatic circumstances of Jordan. The suggested layer (outside, limestone, middle, foam concrete, and internal, plaster) has a (U-value of 0.57 W/m2 K), which matches the Jordanian energy consumption regulations completely. An analysis of the dew-points on a seasonal basis and thermal steady-state analysis shows that the wall is effective to resist hot summers and cold winters of Amman. Vapor diffusion calculations are done using local climatic data to prove that the material diapasons that the material sequence is effective in vapor retarding interstitial condensation in extreme situations. The need in a balanced ratio of vapor resistance of inner and exterior layers to provide proper moisture control is emphasized by design nomographs and vapor resistance charts. Foaming of low-conductivity concrete has the effect of reducing the factor of (36–47) % by a ratio of normal concrete walls, which is an increase in the energy efficiency and the comfort of the interior. Analysis of moisture migration underlines the necessity of an adequate vapor resistance gradient to prevent moisture accumulation and to be sure of internal surface temperatures being above dew-point during the year. The results confirm the feasibility of use of thermal insulation in the concrete sandwich system to derive sustainable and energy efficient multilayer envelops as per the demands of Jordanian environment.