A method for making a polymer with a porous layer from a solid piece of polymer is disclosed. In various embodiments, the method includes heating a surface of a solid piece of polymer to a processing temperature below a melting point of the polymer and holding the processing temperature while displacing a porogen layer through the surface of the polymer to create a matrix layer of the solid polymer body comprising the polymer and the porogen layer. In at least one embodiment, the method also includes removing at least a portion of the layer of porogen from the matrix layer to create a porous layer of the solid piece of polymer.