The Spaniard has spent the last five years of his career at Spanish squad Movistar, but felt the time had come to begin a fresh new chapter in his career.
"Sky is a reference and it was an opportunity I couldn't let slip. It means starting a new chapter and changing to a team that I've always admired for how it operates. It's perfect," he told Spanish website Biciciclismo.
"One thing that motivates me is working once again with Xavi [Xabier Artetxe], who I've known since I was an amateur, in the same team and with all the tools at our disposal."
Intxausti, 25, has shown himself to possess a great deal of potential, finishing eight overall in the 2013 Giro d'Italia and 10th at the 2012 Vuelta a Espana, with stage wins at the 2013 and 2015 editions of the Giro.
"Apart from individual results, I have contributed and helped the leaders in the important races. I am satisfied because I've also shone when I've had the opportunity," he said.
Intxausti leaves behind close friends at Movistar and finds himself with different teammates at Sky. One of them, for whom he will likely provide support, is Chris Froome, who won the Vuelta a Andalucia and the Criterium du Dauphine this year – races where Intxausti was a close third and fourth respectively.
"[Igor] Antón, [Jonathan] Castroviejo, the Izagirre borthers… we'll carry on having the same friendship, which is the important thing. That's something that is going to last forever, even though we may now by rivals in the races."
Intxausti, Michal Kwiatkowski (Etixx-Quick Step), Mikel Landa (Astana), Danny van Poppel (Trek Factory Racing), Michal Golas (Etixx-Quick Step), Alex Peters and Gianni Moscon are Sky's other new signings for the 2016 season.