The TV star, 49, prefers to keep his personal life away from the spotlight, especially when it comes to their little ones, Isla, six, and two-year-old Jack, so their large property in the capital allows them plenty of privacy.
But it seems Dec and Ali are set to improve upon their ever-expanding home even more, thanks to Dec snapping up a multi-million neighbouring property.
According to reports, the BGT star splashed over £2 million on the house after it became apparent that the "eyesore" home needed renovation…
Metro Online reported that the property, which is next door to Dec and Ali's current luxury abode in Chiswick, had been converted into flats.
However, the famous couple decided to snap up the house at the end of 2023 and applied for planning permission to extend it at the side and rear.
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It's not yet known if Dec will keep the property as an extension of their family home, or indeed decide to rent it out.
However, if they keep the home, the proximity will afford even more space and privacy for the family of four.
Dec and Ali's £7 million Chiswick home
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Dec and Ali, who wed in 2015, have lived in their home in Chiswick, west London, for many years now.
The TV star bought the seven-bedroom property back in 2006 for £1.9 million, meaning the house has increased tremendously over the years and is now thought to be worth a whopping £7 million.
Dec hasn't shared too many photos of himself inside his property, but from the snaps we have seen, the décor is stunning.
A photo of the star inside his living room showed off the neutral theme that he and Ali have opted for, including a cream sofa with pops of colour including blue cushions and a dark wooden side table.
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The neutral tones continue throughout the house, including in this room that features a silver metallic console table with a vase of flowers, framed photo and a bottle of Jo Malone fragrance on display.
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During the coronavirus lockdown, Ant and Dec were often posting hilarious TikToks at home with their fans, and one snap featured Dec posing in his huge garden, which had stylish horizontal-panelled fences, with huge trees and a lawn area, offering plenty of greenery despite living in the big smoke.
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The home not only boasts seven bedrooms, but it features a swimming pool and cinema room, meaning their little ones have endless entertainment at home.
The house also features an at-home gym, aptly decorated in a black-and-white theme to pay homage to Dec's beloved Newcastle FC, for when the couple wants to focus on their fitness game!