A protective fabric jacket for placement on an object to be protected from excessive heat includes a first layer; a second layer; and an intermediate spacer fabric layer that is disposed between the first layer and the second layer. The first and second layers are attached to the intermediate spacer fabric layer to form a layered structure. The intermediate spacer fabric layer comprises a flexible honeycomb or octagonal shaped spacer fabric that has a plurality of cells defined therein. The protective fabric jacket also includes a settable material that disposed within the cells and includes a cementitious mixture and one or more organic polymers and is settable to a hardened material.