I am not quite following the timeline. The owner filed chapter 13, at some point "during" the chapter 13, the owner contracted with a contractor to have some work done. Something went amiss and the contractor feels he is owed money and has filed a mechanic liens. If that is the case, the answer is yes, the mechanics lien can be placed and perfected because the underlying debt (the contractor's right to money, allegedly) occurred after the BK was filed.
In any event, you should be discussing the particulars with your chapter 13 bankruptcy attorney. To many if this, if that, but then...type of scenarios to flesh out here.
I agree with the other lawyer: the timeline is not clear at all. Chapter 13 cases are a lot more complex than most people realize and they typically extend for five years. If you are the debtor, and still 'paying into the plan', you violated the plan by even contracting for construction without the court's permission. If the chapter 13 was fully paid and discharged (or otherwise dismissed) then the contractor did nothing wrong. You need to talk to your lawyer about everything that happened.
Your question implies that the work was contracted and completed after you filed for Chapter 13 bankruptcy. If this is the case then yes, the mechanic's lien can be filed for the post-petition work if it otherwise meets the requirements under state law, such as the work actually being completed.