The 29-year-old midfielder thumped in the Robins' opener at the Abbey Stadium after 10 minutes after Craig Braham-Barrett's throw-in was cleared to him on the edge of the box.
It was his second strike of the season in his 60th successive League Two appearance since joining Cheltenham from Shrewsbury Town in the summer of 2013.
"It was decent wasn’t it!" Richards said with a beaming smile. "It sat up nicely for me, I had some time and caught it sweet and it’s gone over the keeper and into the net.
"I have scored a few decent ones, but I am happy with that one. It’s definitely up there with my best strikes."
Cambridge levelled through Kwesis Appiah in the 25th minute, but Terry Gornell's fourth goal in three appearances sealed the Robins' second successive win 10 minutes after half-time.
"It is always nice to score early and we played some good football early on with our front two (Gornell and John Marquis) working so hard and making it difficult for them," Richards said.
"The conditions were difficult, but we dealt with it well and deserved the three points.
"Cambridge went direct and started using the wind, but we got behind the ball and defended well, with the back three superb.
"They had a shot that hit the bar from distance and Trev (Carson) made a great save, but Terry has been brilliant since he came back into the team and vital to the success we’ve had in recent games.
"John has worked extremely hard and their energy up front was vital. Everyone is really happy in that dressing room."