All apartments and houses will have a non-indoor smoking policy in place. This is for cleanliness, and health benefits. At the very least, smoking imposes nicotine on the walls that must be cleaned and painted in order to maintain a rentable environment. This will pass against your security deposit if you have been found smoking in the unit.
I am not telling you to not smoke. If you wish to continue with this habit, that is your choice. You are just not allowed to smoke inside the building at all. To comply with the lease, you would have to go outside to smoke. This will be an inconvenience to some, but assuming that I would have my own realty company, this will be made known to any tenant. Anyone caught smoking in the unit will be given a warning. If in violation again, the tenant will face an eviction, and their security deposit surrendered to repair the damages.