Q: The Manhattan co-op where I have lived for 20 years will become a smoke-free building in January. I am a 76-year-old smoker. It’s a bad habit that I picked up in college, but I still enjoy it. I don’t think I should be forced to sell my apartment or move because the rules changed. I understand that a new policy could affect new owners, but shouldn’t there be an exception for longtime residents? Do I have any right to challenge this?

A: Co-ops can change their rules, enacting new ones that affect both new and longstanding residents. When you buy in a co-op, you do so with the understanding that if a new policy is enacted you will follow it, even if you don’t agree with it.

Buildings usually change smoking rules by amending the proprietary lease, a process that requires the support of two-thirds or three-quarters of all shareholders, depending on the co-op’s rules. “Most buildings that have gone smoke-free have done so because of a strong groundswell from their apartment owners wanting it,” said Aaron Shmulewitz, a real estate lawyer and a partner at the Manhattan law firm Belkin Burden Wenig and Goldman.

With a large majority voting for the measure, the board will presumably be under pressure to enforce it. Assuming the rule was properly enacted, you do not have many options other than to comply. “Since smokers are not a legally recognized protected class, smoking bans are not discriminatory and should be enforceable,” said Dennis H. Greenstein, a real estate lawyer and a partner in the New York City office of the law firm Seyfarth Shaw.