Is it legal to limit number of tenants residing in a unit?

[David Lorenz]

Hi BP!

I'm in the tenant screening process with my first rental (a duplex in Philly). The bottom unit is a 2 bedroom that's roughly 700ish sq ft. I would prefer to limit the number of tenants in that unit to 2 (1 per bedroom). Am I legally allowed to turn down a tenant that would be living there with another adult and 2 kids for example? I have nothing against renting to a family as I have kids myself. However, I would prefer limiting the number of tenants as it's not a large unit and I believe it would reduce the wear and tear on the property.

Thanks!