When Gareth Hughes was a boy, he imagined how wonderful it would be if an ice fishing hut sank in the spring. He wasn't a destructive child, quite the opposite. He thought an airtight ice fishing shack would be a wonderful underwater cottage.
As he grew older, he became obsessed with the idea of an underwater cottage. He hiked to remote mountain lakes to find an ideal location. He learned how to scuba dive so he could reach it. And of course he built it.
He began with a heavy steel sea-going cargo container. He welded two thick metal plates near each end to form ballast tanks. Garth planned to have his cottage float a couple meters above the bottom of the lake, yet well below the surface. He would tether the cottage to the bottom of the lake with strong cables, and adjust the ratio of air to water in the ballast tank to achieve the proper buoyancy.
He used a third metal plate to divide the main chamber in half. One room would be used for entering and leaving the cottage through an aperture in the floor; the other half would be the living area. For added safety, Garth installed an emergency exit in the floor of the living area as well as a waterproof door between the two compartments.
He cut dozens of small holes in the ceiling and filled them with thick plexiglass plugs. He made a small buoy to float on the surface above the cottage; it would be connected to the living space by sturdy ventilation tubes. He was almost home.
A logging company pilot offered to illegally fly his underwater cottage to a remote mountain lake using a heavy logging helicopter for $4,000, but Garth turned him down. He could easily have afforded the $4,000, but decided he preferred the concept of an underwater cottage to the reality of one.
He enjoyed looking out the window of his home at his creation for many decades until he died at age 71. And despite legal and logistical difficulties, his daughter honored the only request in his will.
Gareth Hughes is buried in his underwater cottage under almost five miles of water in the Java Trench. There's no reason why the doors shouldn't work.