Surveys: do you need one? / by S. Joshua Brincko

As explained in the short video above, a survey is a drawing prepared by a licensed surveyor that documents the exact location of your property lines. To learn more, read the post below, and also watch the more thorough video at the end of the post.

Why are surveys important, and why do you need one?

Knowing where your property line is located is important if you are building a new structure or adding onto one. If you want to expand your kitchen into your back yard, you first need to know if you are ALLOWED to build that addition in the space that’s available in your back yard. A surveyor can determine exactly where your property lines are located, and your architect can use that to determine how far away your house must be from each property line. This is known as a setback. Different cities and different zoning classifications have different setbacks for buildings, decks, and garages from front, side, and rear property lines. There’s also required setbacks from things like steep slopes, wells, bald eagle nests, septic tanks, streams, etc. A surveyor can accurately document these things, so you can be sure your project gets built legally in an area that the city allows. You wouldn’t want an inspector to require you to tear down your home because it’s built too close to a property line.

Let’s expel a myth…please!

YOUR FENCE IS NOT YOUR PROPERTY LINE.

YOUR SIDEWALK OR YOUR CURB IS NOT YOUR PROPERTY LINE.

Or when the old guy that used to live there said, “the rock by the cedar tree is on the property corner,” THAT DOESN’T MEAN A DAMN THING.

The building department will not give a rip about where you think your fence is, or whatever the old guy in the neighborhood told you. A survey is the only legal document that can determine (and prove) where your property lines are, and most importantly, how far your house is located from those property lines. Without a survey, your architect cannot know exactly where to design your project, and the building department will not know if they can approve your drawings to issue a permit for construction.

Another reason a survey is often required would be to document lot coverage. Lot coverage is a percentage of your property that is allowed to be covered by buildings, decks, patios, or some combination thereof. A surveyor locates the exact locations of all these items on a property, so your architect can calculate how much surface area each item is. For example, in Seattle, you are allowed to cover up to 35% of your typical 5000 SF property with structures. Knowing the exact size of the existing house, garage, shed, trellis, deck, etc will enable your architect to know if you are already exceeding your maximum lot coverage or not. Without this information, you cannot be certain that there is any remaining area that is allowed to be covered with a bigger house.

Surveyors also document trees and topography (the slope of your land). This is important because there are some restrictions on removing certain trees, required setbacks from some trees, and the minimum amount of trees (and tree sizes) your property is required to have since trees do a pretty good job of sucking up rainwater to prevent overburdening the sewer systems from stormwater runoff. Knowing the slope of your land also helps your architect to design a building that appropriately fits into the hillside while not requiring too much soil to be excavated and removed (which is very costly). Additionally, some slopes are classified as “steep slopes” when they exceed a certain height or percentage of slope, and your architect needs to know where the exact top and bottom of those slopes are located. The required setbacks (buffers) from those slopes can be maintained with your new project. We also use surveyors to document the height limit of your house, and this is determined by knowing the topography of your land since the maximum height limit is determined by calculating the average height of the ground.

Lastly, a surveyor also documents easements. These are portions of your property that are generally used by someone other than the property owner. For example a neighbor might have a drain pipe going through your yard, and there might be an easement documented that does not allow you to build within that area. Again this is important information your architect needs, so he or she will be able to design a project for you.

In some instances a survey is not required. This takes a bit of discretion and risk, but if your property has no slope and the building will be nowhere near your property lines, nowhere near the maximum lot coverage, and not even close to the maximum height, then your architect and building department can work with certainty knowing that the requirements for these items will not be exceeded. So how much tolerance is there? In my experience, if you are required to build at least 5’ away from a property line, and you are proposing to build 7’ away, then that additional 2’ buffer will usually suffice. It’s sort of like speeding: 5 or 10 mph over the speed limit, and you’re likely fine - but you never know.

Most properties have never been surveyed, so nobody really knows where the property lines are located until a surveyor calculates and measures it. They do this by triangulating other known points that have been previously documented on other surveys which could be several blocks away. They work their way back to your property from those other landmarks using trigonometry and expensive GPS enabled equipment with lasers and other fancy technologies to make long measurements. They don’t bust out a tape measure for this stuff. They get accurate within 0.01’ tolerance (I’ve been told).

This gets increasingly important in older cities like Seattle where most homes were built before there were rules governing setbacks. Your existing house may already be built over your setback line. This is called being “grandfathered” or an “existing nonconformity.” Don’t be alarmed - actually be glad. If it was built before the rules existed (and if you and your architect can prove it), then you can continue to keep your house over the setback line. And more importantly, in some of these circumstances, you are actually allowed to build your new addition along the same continuation of that line. In other words, you may be allowed to continue to break the rules with your new addition too! Your architect can help advise you on whether or not that is an option.

What should you expect to pay for a survey? This depends on what you need documented, how big your property is, how complex it is, and whether or not it’s easily accessible. I’ve seen surveys range from $1500 to $10,000. They are usually under $5000 though. A survey is a very valuable investment that enables your architect to properly design your project and keep you compliant with the land use codes. The surveyor provides the architect with a pdf file and an autocad file that he or she can work with on the computer with 100% accuracy. At a minimum, the architect needs a survey with the property lines and perimeter of the existing structures drawn, and in most cases, the trees, slopes, and easements must be documented, so your architect may determine required setbacks, height limit, and maximum lot coverage calculations.

The full video below takes a deeper dive into all things surveys, and it includes a basic tutorial on how to read a survey drawing.

If you’d like to learn more about our design process, visit www.josharch.com/process, and if you’d like to get us started on your project with a feasibility report, please visit www.josharch.com/help