Good fences may make good neighbors, but they do not make a property line

More and more municipalities around California, and even nationwide, are requiring that new residential projects, in particular, submit updated boundary line surveys before receiving a building permit. This is partly because property owners do not always have accurate property line information, which is especially critical when designing and building an accessory dwelling unit (ADU) right up to what is believed the property line. The ADUs, to clarify, are growing in popularity and consist of building and/or building out a room, studio, or even an apartment under, behind, or next to your primary residence. The ADUs have become popular in recent years as the housing crisis worsens and property prices continue to climb. Therefore, an ADU is a great way to 1) increase your living space footprint, 2) create a source of income by renting the ADU out, and/or 3) provide housing to a loved one on your own land.

Since oftentimes, such as in San Francisco, the land is at a premium and scarce, people are building right up to their “property line,” which is not always the fence line. Therefore, cities across the Bay Area require new buildings to ensure that they have accurate property boundaries on their building plans to avoid future conflicts and lawsuits, which occur more often than we might think.

The property line or boundary delineates the perimeter of the lot you own. It is typically tied to a street “monument,” which is basically a pin or plaque on the street from where you can dimension the length and angle to a corner on the boundary. From there, using bearings and distances, you can form the entire property perimeter. And although this is relatively straightforward, mistakes can be made through human error, such as 1) using the wrong monument data and 2) utilizing erroneous lengths and bearings. Additionally, in a case I experienced, the new owner of a house in a residential development had moved the stakes before the fence between his and his neighbor’s house was constructed, in essence, giving himself a larger lot. Once the fence was up, everyone assumed, naturally, that that was the property boundary. It was not until several years later that the truth came out.

In general, whether knowingly or unknowingly, a property owner will be held liable if they build beyond their property line and into the neighbors. The consequences might include expensive lawsuits, having to pay their neighbor to purchase the amount of property they have encroached on, and even being forced to demolish the new construction. Therefore, it is critical, especially when building a substantial structure up to the property line, that owners, architects, engineers, contractors know exactly where the boundary line is. It is also crucial to remember that foundations and anything else built underground must also fall within the property line, not just the walls protruding from the ground. The same applies for fences; and although these are typically much cheaper than concrete structures, you must be sure that the fence you build, including the fence footings, gravel filters, drainage pipes, and so on, fall within your property line unless you have a written agreement with your neighbor to place the fence on the boundary and then there is an easement for the fence structure.

If you have any questions, comments, or wish to receive an estimate to perform a boundary survey, topographic survey, or any civil design work, don’t hesitate to contact Sustainable Civil Engineering (SCE) at 415.800.3035.

Good fences may make good neighbors