The Hidden Passage Retreat
This custom build features a 32-foot tunnel running under the deck to connect a window catio to the main 8’ wide x 4’ deep x 8’ tall enclosure, transforming tight under-deck space into a secure feline highway. Built with pressure-treated lumber and enclosed in 1x1 black PVC-coated welded wire fencing, the freestanding main catio sits on a deck base and is topped with a clear polycarbonate roof for bright, year-round protection, all left in a natural wood finish with no paint or stain. Inside, shelves and ramps create layered climbing paths leading to a large cat cubby, while a floor-to-ceiling natural scratch post adds enrichment and a rustic touch. Complete with a human access door, this design turns overlooked backyard space into a safe, adventure-filled outdoor retreat.