Internal casing hoop for a turbomachine, the hoop being centred on a longitudinal central axis and being characterised in that it includes: - a main body, that is centred on the longitudinal central axis, that includes two longitudinal ends and that is delimited by a radially internal surface and a radially external surface relative to the longitudinal central axis; - a thermal insulation envelope, that includes: • a lateral covering portion entirely covering the longitudinal ends of the main body; • along a section transversal to the longitudinal central axis, an exterior covering portion entirely covering the radially external surface of the main body; • along a section transversal to the longitudinal central axis, an interior covering portion entirely covering the radially internal surface of the main body; the lateral portion connecting the interior and exterior portions; and - a protective envelope, that at least partially covers the thermal insulation envelope and that includes, along a section transversal to the longitudinal central axis: • a radially external protective portion at least partially covering the exterior covering portion; and • a radially internal protective portion at least partially covering the interior covering portion; and in that the thermal insulation envelope has a porous structure with a volumetric porosity greater than or equal to 50% and has a porosity higher than the one of the main body. - a main body, that is centred on the longitudinal central axis, that includes two longitudinal ends and that is delimited by a radially internal surface and a radially external surface relative to the longitudinal central axis; - a thermal insulation envelope, that includes: • a lateral covering portion entirely covering the longitudinal ends of the main body; • along a section transversal to the longitudinal central axis, an exterior covering portion entirely covering the radially external surface of the main body; • along a section transversal to the longitudinal central axis, an interior covering portion entirely covering the radially internal surface of the main body; the lateral portion connecting the interior and exterior portions; and • a lateral covering portion entirely covering the longitudinal ends of the main body; • along a section transversal to the longitudinal central axis, an exterior covering portion entirely covering the radially external surface of the main body; • along a section transversal to the longitudinal central axis, an interior covering portion entirely covering the radially internal surface of the main body; - a protective envelope, that at least partially covers the thermal insulation envelope and that includes, along a section transversal to the longitudinal central axis: • a radially external protective portion at least partially covering the exterior covering portion; and • a radially internal protective portion at least partially covering the interior covering portion; and in that the thermal insulation envelope has a porous structure with a volumetric porosity greater than or equal to 50% and has a porosity higher than the one of the main body. • a radially external protective portion at least partially covering the exterior covering portion; and • a radially internal protective portion at least partially covering the interior covering portion;