http://www.househacker.com/ househacker/tags/bathtub
Skills and materials honed and tested in the demanding boatbuilding industry mean you don't have to worry about your bath ever springing a leak. Indeed, keep the stopper firmly in and you could probably paddle your bath quite safely. And because our baths rely on marine technology they are designed for a far more ravaging environment then your bathroom.

Furthermore:

Each wall is built using a strip building technique where narrow wooden strips are locked one to the next using a boat building technique called cove and beading. This technique means the walls behave as single sheets of wood. Each strip is individually cut, placed and bent to perfectly shape and seal your bath. The floors of each bath are built from over 25mm (1 inch) of wood. This might sound excessive but it prevents any possibility of creep and sagging with age, ensuring your bath floor will always remain sound and true.

The baths must be quite a hit with people as the site is closed to new orders, according to a notice on the homepage. That or it just takes them years to build one.

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