The house was built by Sir John Trevor I, a prominent courtier of King James I, in about 1610. Sir John died in 1629 and his wife in 1643, leaving the house unoccupied as the English Civil War broke out. It was twice raided by the Roundheads, but continued to be passed down to Trevor descendants until the early 20th century. During the Second World War the house was requisitioned by the War Office to billet soldiers. In 1945 it was sold to an auctioneers company, which used it for storage. By the early 1950s, Plas Teg was in a state of advanced decay and under threat of demolition. Following a public outcry, the derelict house received a Grade I listing from Cadw, protecting it from demolition. A Trevor descendant, Patrick Trevor-Roper, purchased the house and partially restored it with funds from the Historic Buildings Council. He then leased out the house until 1977, when Mr and Mrs William Llewelyn bought the house. The couple only used parts of the ground floor but the rest of the house became little more than a ruin.
Current ownership
Fortunes dramatically changed in 1986 when Cornelia Bayley acquired Plas Teg for £75,000. She carried out a series of works at a cost of £400,000, £199,000 of which was funded by Cadw. Ten months after purchase, the house was opened to the public and still is to this day. The county of Flintshire is said to be a land of spirits and hauntings. One notable case is that of the grey lady, described as the most popular of such entities in North East Wales. The old woman is reported to have been seen moving across the A541 adjacent to Plas Teg into the path of traffic.
In media
Plas Teg is said to be one of the "most haunted" houses in Wales and has featured on ITV's Extreme Ghost Stories and Living's Most Haunted programme on two occasions. The second occasion was featured as part of the HalloweenMost Haunted Live! series on 31 October 2007. It was also featured in Ghosthunting With...Girls Aloud in 2006, where the girls visited the house as their first location, where they claimed to have experienced paranormal activity. On 4 March 2010, Plas Teg was the subject of a Channel 4 television programme presented by hotelier Ruth Watson as part of her Country House Rescue series. The episode was rebroadcast on 29 September 2011 and again in February 2012. In 2015, the house was shown as a feature in the Channel 4 series Obsessive Compulsive Cleaners. In 2019, the house features in Hidden Wales with Will Millard.