A vacuum vessel (100, 200) comprising: a shell (302, 402) including a continuous surface layer (305, 405) with a shell locking portion (306, 406); a liner (304, 404) including a continuous surface layer (308, 408) with a liner locking portion (309, 409), where the liner locking portion (309, 409) and the shell locking portion (306, 406) interlock the shell (302, 402) and the liner (304, 404); wherein the liner locking portion defines a U-shaped recess and the shell locking portion defines a U-shaped protrusion that projects into the U-shaped recess of the liner locking portion to interlock the liner locking portion and the shell locking portion; or the shell locking portion defines a U-shaped recess and the liner locking portion defines a U-shaped protrusion that projects into the U-shaped recess of the shell locking portion to interlock the liner locking portion and the shell locking portion; the vacuum vessel (100, 200) further comprising a panel coupled to the continuous surface layer of the shell to form a cavity defined by the panel and the continuous surface layers (205, 208) of the interlocked shell and liner; and a vacuum seal including a first sealant layer (322, 422) and a second sealant layer (324, 424) disposed along an interface (311, 411) between the continuous surface layer (305, 405) of the shell (302, 402) and the continuous surface layer (308, 408) of the liner (304, 404), where at least the first sealant layer (322, 422) is continuously disposed along an interface (325, 425) between the U-shaped shell locking portion (306, 406) and the U-shaped liner locking portion (309, 409) to allow the cavity (320, 420) to maintain a partial vacuum relative an ambient pressure outside the cavity (320, 420). a shell (302, 402) including a continuous surface layer (305, 405) with a shell locking portion (306, 406); a liner (304, 404) including a continuous surface layer (308, 408) with a liner locking portion (309, 409), where the liner locking portion (309, 409) and the shell locking portion (306, 406) interlock the shell (302, 402) and the liner (304, 404); wherein the liner locking portion defines a U-shaped recess and the shell locking portion defines a U-shaped protrusion that projects into the U-shaped recess of the liner locking portion to interlock the liner locking portion and the shell locking portion; or the shell locking portion defines a U-shaped recess and the liner locking portion defines a U-shaped protrusion that projects into the U-shaped recess of the shell locking portion to interlock the liner locking portion and the shell locking portion; the vacuum vessel (100, 200) further comprising a panel coupled to the continuous surface layer of the shell to form a cavity defined by the panel and the continuous surface layers (205, 208) of the interlocked shell and liner; and a vacuum seal including a first sealant layer (322, 422) and a second sealant layer (324, 424) disposed along an interface (311, 411) between the continuous surface layer (305, 405) of the shell (302, 402) and the continuous surface layer (308, 408) of the liner (304, 404), where at least the first sealant layer (322, 422) is continuously disposed along an interface (325, 425) between the U-shaped shell locking portion (306, 406) and the U-shaped liner locking portion (309, 409) to allow the cavity (320, 420) to maintain a partial vacuum relative an ambient pressure outside the cavity (320, 420).