The Tigers improved to 19-0 and Shelton fell to 16-2.
For the Gaels, Erik Kocur led the way with 18 kills, four digs and one ace, Grant Fevrier added seven kills, five digs and one ace, T.J. Nicholas notched nine kills and four digs.
Karl Liapunov paced Ridgefield with 15 kills and one ace, while Henrik Liapunov tallied 30 assists and Mark Liguori had seven digs and eight kills.
Shelton will compete in the Southern Connecticut Conference boys volleyball playoffs on Wednesday, May 27. The Gaels are seeded No. 1 and will host Daniel Hand of Madison, the fourth seed, at 6 p.m. In the other semifinals, second-seeded Xavier High of Middletown will host third-seeded Cheshire at 5:30 p.m.
The final is set for Friday, May 29, at 6 p.m. at the home of the higher seed.