Accepted Answer

Hello XXXXXXXXX, and thank you for your question.

The property line itself has no width dimension - it's just a line.
You next door neighbor certainly cannot put any concrete over the line, extending onto your property.
But whether or not he can put concrete right up to the line, or whether he needs to adhere to a particular setback distance from that line, is a matter of local zoning.

What you need to do is call or visit your local zoning official. He or she can determine for you which district or zoning division you and your neighbor are located in, and then tell you what the zoning regulations are for that specific location and situation.
Sometimes setbacks vary based on whether the line is along a side yard or rear yard.
Sometimes property owners must adhere to setbacks for structures of a certain height, but not for anything lower than that.
So, as you can see, this can be a bit complex, and can vary greatly from one city to another, and even from one zone to another within the same city.

As for the isse of where exactly the property line is: it may be very difficult to get your local officials to actually enforce any setbacks if the property has never been surveyed. Some cities and towns also have official elected or appointed "fence viewers" who have the authority to settle this type of dispute, sometimes without a survey. But it may be necessary to invest in a survey of your property in order to pursue this issue in the long run.


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Expert:	MJ
Pos. Feedback:	100.0 %
Accepts:
Answered:	10/3/2009

Architect

Licensed Architect, LEED® AP, NCARB Certified, M.Arch degree, 10+ years experience