Chase Budinger added 12 points and 10 rebounds for the Rockets, who got another strong effort from their reserves to beat the Suns for only the second time in the last nine meetings. Courtney Lee and Patrick Patterson also scored 12 points apiece off the bench for Houston.
The play of the reserves gave valuable rest to the Rockets' starters leading up to their road trip, which begins Saturday night in Minnesota.
The Rockets' reserves scored 50 points and pulled down 23 rebounds. They also preserved Houston's big lead in the second half to let the starters rest before Saturday night's game in Minnesota.
"The bench is really getting that chemistry together," Budinger said. "We're getting used to playing with one another, we start finding where guys like the ball, and also we're bringing energy out there. We're trying to run more."
Houston's bench is averaging 49 points over the past five games.
"It is challenging, just because you're going against NBA players every night," Patterson said. "But when you're clicking like that, we're running the offense, we're utilizing our advantages and it's great. We can do that with any team. It's just all about playing hard and just doing it."
Lowry said it was also the kind of performance the entire team needed after losing badly to Minnesota on Monday and then blowing a 19-point lead in San Antonio on Wednesday.
"We played well, we got the ball out fast, we got up and down, made some shots and got it going early," Lowry said.
Marcin Gortat had 15 points and 12 rebounds and Shannon Brown scored 12 for the Suns, who've lost five of their last seven. Houston had a 49-39 rebounding edge and held Steve Nash to six points and nine assists.
Nash's only made baskets were two 3-pointers, and he also coughed up four turnovers.
"We were having problems scoring," Nash said. "We hung pretty close for the first eight minutes or so, then instead of going back to getting the game closer, we let it get away from us."
Nash had four assists in the first six minutes, and the Suns took an early 14-13 lead. Nash and Grant Hill went out for a rest with 3:50 left in the first quarter, and Houston finished with a 15-6 spurt to take a 30-20 lead.
The Rockets' reserves shot and rebounded well early in the second quarter to preserve the double-digit margin. Nash and Hill returned, but Houston stayed in control, stretching the lead to 45-28 on Budinger's 3-pointer from the corner.
Houston's bench scored 21 points in the second quarter, and the Rockets led 59-39 at the break. Houston outrebounded Phoenix 29-18 in the first half, with Luis Scola, Lowry and Patterson grabbing six boards apiece.
The Suns' offense continued to sputter in the third quarter, even with Nash on the floor. Phoenix started the second half 4 for 10 from the field, and the deficit hovered around 20.
Phoenix couldn't slow Houston much, either. The Rockets shot 43 percent (9 for 21) in the quarter and led 80-61, despite five turnovers.
Most of the starters from both teams sat out the final quarter, getting valuable rest since both play again Saturday. The Suns fly home to meet Charlotte, then face a demanding two-day trip with games in Atlanta on Monday and Milwaukee on Tuesday.
"We need to play harder and play `grown-man' basketball and not get pushed around," Phoenix coach Alvin Gentry said. "You have to compete and match energy with energy. I wasn't pleased with anything we did."
The Rockets held Phoenix to 19 points in the fourth to win for the 21st consecutive time when holding their opponent below 90 points.
The Rockets' first-half points total was a season high. ... Houston sent first-round draft pick Marcus Morris to Rio Grande Valley, the team's developmental league partner. The 6-foot-9 Morris was selected by Houston with the 14th overall pick, just after his twin brother Markieff was taken by Phoenix. Morris sprained his left ankle in a D-league game on Jan. 12, but general manager Daryl Morey says Morris is cleared to play. Morris has averaged 22 points, 9.3 rebounds and 2.3 assists in four starts for Rio Grande Valley this season. ... The Suns are 1-13 when trailing at halftime. ... Phoenix lost to the Rockets for only the seventh time in the past 22 meetings.