"Go home to your family Harry, the Hogwarts Express is about to depart for another year – enjoy the time you’ve got left...."
-- Hermione Granger (CC1.5)
Amos Diggory and Delphi visit Harry there (CC1.6), we see Harry giving his children pre-Hogwarts start-of-term gifts (CC1.7), having nightmares about Lord Voldemort (CC1.9) and discussing the aftermath of a Ministry of Magic public meeting (CC1.15). Harry has a vision of Voldemort and his son Albus (CC2.2), and then a fight and rapprochement with Draco Malfoy (CC2.13, CC2.15). He has another nightmare about the return of Lord Voldemort (CC3.13) and finally a message from his son Albus (CC4.6).
As they can travel by magic, wizarding homes can be in any part of the UK. Therefore the exact location of Harry and Ginny's house is unknown. We do know that it isn't in Harry's childhood home, Godric's Hollow, as Albus tells his friend Scorpius Malfoy that he has always refused to visit their with his father in the past (CC4.3).
From the Web
Pottermore: Harry Potter and the Cursed Child
The theatre production opened in the West End of London at the Palace Theatre on 31 July 2016: Harry Potter and the Cursed Child, Parts One and Two