Abstract: In an example, the thermal insulation is prepared by blending water with the following ingredients including a hydraulic cement in an amount from about 5% to about 25% by weight, a reinforcing fillers including clays, sands, limestone powders, perlites, re-dispersible polymer powders, and fibers in an amount of from about 0% to 40% wt, foaming agents from about 0.02% to 4.0% wt, a rheological agent in an amount of about 0.05% to 4.0% wt, a curing accelerator in an amount of about 0.01% to 2.0% wt, a curing retarder in an amount of about 0.01% to 1.0% wt, and a water repellent agent in an amount of about 0.02% to 4.0% wt, wherein a secondary pore structure is created by mechanical frothing the mixture with air in an amount of about 20% to 80% by volume and the composite foam insulation is subsequently dried and cured in a mold.