Guinness World Records has confirmed that the structure created on 17 August 2010 now holds the record.
The house measures 5m (15ft 5in) by 2.37m (7ft 9in) and took just four hours to build.
All the materials used to construct the house were either donated by local businesses or sourced from the trust's own nature reserves.
A local builder made the timber frame, which was filled with stone, bricks, pre-drilled concrete, wooden blocks and plant material.
Red mason bee
The house was designed for solitary bees such as the red mason bee
The house was designed specifically to encourage the nesting of solitary bees which are considered to be as important to the food chain as bumblebees and honeybees.
Amanda Hamley managed the bee house project: "This is brilliant news. The house makes a great new visitor attraction for the nature reserve.
"It should also serve to remind people of the plight of bees - with many species in serious decline - and hopefully encourage Kent residents to create simple bee houses for their own gardens."
The trust's Ray Lewis added: "We are really looking forward to seeing the structure come alive when the first bees take up residency and start building their nests this spring."
