Ard's new record coincides with the release of the latest film in the franchise, Transformers: Rise of the Beasts.
Ard said his love of the Autobots and their Decepticon rivals began when the original animated series premiered in 1984, and it wasn't long before his mother bought him his first Transformer, Cliffjumper, an Autobot who transforms into a Porsche 924 Turbo.
The collection is now housed in three separate rooms, which each represent an era of the franchise.
Ard, an artist, said he has also started designing his own Transformers, which he hopes will eventually become a part of the franchise's official canon of characters.
"I hope to add to the Transformers multiverse someday. I have 300, but 30 visually ready for illustration, modeling and eventually 3D printing," he told Guinness World Records.