Shafilea, who had wanted to be an attorney, had been reported missing by her Pakistani parents.
The girl's dismembered body was found on a riverbank in February 2004, months after she disappeared in 2003.
The death was the final act in a long-running effort by the couple to get their daughter to conform to their beliefs, Detective Superintendent Geraint Jones told reporters.
"When this failed, they murdered her, a vile and disgraceful act," he said.
In sentencing the couple, Evans said they had used "intimidation, bullying and ... physical violence" in an effort to force her to adopt ways they viewed as more culturally appropriate.
"Your problem was that, in what you referred to as your 'community,' Shafilea's conduct was bringing shame upon you and your concern about being shamed in your community was greater than your love of your child," Evans told the couple, according to a transcript provided by court officials. "In order to rid yourselves of that problem, you killed Shafilea by suffocating her in the presence of your other four children."
Melissa Powner, a friend of the slain girl, told reporters the conviction "brought our friend the justice she deserves." "If there is one thing that we pray will come from this, it is that her beautiful face and tragic story will inspire others to seek help and make them realize that this kind of vile treatment, no matter what culture or background they are from, is not acceptable and there is a way out," Powner said in a statement to reporters.
Both had categorically denied involvement in their daughter's death until the mother pointed the finger at her husband.
On Monday, Farzana Ahmed testified that she had tried to intervene to protect the girl, but her husband pushed her away and punched her, according to CNN affiliate ITV. She said she was "extremely scared" when she fled the room and stayed in a bedroom with other children until she heard a car leaving 20 minutes later.
When her husband returned alone, she said, she asked where her daughter was.
"If you care for your dear life and that of your children, don't ever ask me this question again," he told her, ITV reported.
Farzana Ahmed testified Monday that only one of their children, Mevish, was present when she saw her husband attacking Shafilea.
She probably did that to save her own hide, since another daughter, Alesha, testified that her mother was just as guilty; and from her testimony, it seems as if Farzana was the instigator.
Alesha said her parents were angry that Shafilea was wearing a short-sleeved, V-neck top, and no sweater, on the night she was killed.
"Just end it here," Farzana said to Iftikhar, according to their daughter.
They pushed Shafilea onto a sofa and suffocated the struggling girl, Alesha testified.
Prosecutor Andrew Edis called it "an act of suffocation by both parents acting together."
Police will review evidence that came out during trial and could decide to seek additional charges, Detective Chief Inspector Chris Ankers said.
They should have stayed in Pakistan if they had no intention of integrating, or at least allowing their children to do so. Now they get to spend a good chunk of their lives behind bars. I'm sure Allah would be so proud of them.
Shafilea can finally rest in peace. Some justice has been done.