If you live out side of a city proper there’s a good chance that you’re on a septic system.  It’s time to sell your home.  What do you do (do)?

Your experienced Realtor will help you make all of the tough decisions based on your knowledge about this disperser of the doo doo.

In a perfect world I convince my new listing client into having the septic inspected before the home goes on the market.  This way any problems can be fixed before the closing deadline is looming.  Of course, 9 times out of 10 there are no major repairs to be had, but those words, “septic inspection completed and approved,” make that home that much easier to buy.  If you go the more traditional route, you would most likely have 15 days to get it done after your contract gets signed around. Either way, this is a requirement by King County and it must get done (and pass) before you can close on the sale of your home.  There’s a very good chance you will also need it pumped.

Let’s take one more piece of the selling puzzle and make it less of a mystery.  What happens at a septic inspection?

There is a list of certified OSS inspectors and designers at the King County Health Department’s page. Here you can also find a copy of your As-Built, which you should have a copy of even if you are not in the market of selling.

imageThe day of your inspection you should try your best to clear access to the the tank and to the distribution box so you leave your inspector with as little work as possible.

In this photo, the homeowner did a wonderful job uncovering the access to the tank, but the inspector had to get it to the distribution box.  That’s ok.  Not everyone is going to know exactly how to find all of the pieces.

The first thing the OSS rep is going to do is check the integrity of the exposed pieces.

You can just see Distribution boxthat the corner of this older distribution box is crumbly.  This D-Box did NOT pass the inspection and had to be replaced.  In this case the replacement was just around $700.  You’ll want to find out from your inspector how much something like this would be ahead of time.

The next step will test the durability and clarity of your drain field.


They will drop a hose into the tank that feeds directly into distribution box.  They will then push enough water through that all distribution points will take on water.  This is to make sure the water won’t get backed up with use.  As long as it flows freely, things look pretty good.  In this particular case, they pushed water for about 20 minutes.

After checking a flush, it’s time to check the tank.  In this circumstance the home had been empty for

The pipe seen is how the gray water makes it way to the D-Box.
This is the tank. The pipe seen is how the gray water makes it way to the D-Box.

some time so the gray water was a little low in the tank.  If the water drops below the edge of the pipe through which it exits to the D-box, it could be a sign that there is a small crack somewhere, so in this case they had to fill the tank up with a hose.  Then it’s a waiting game.  Here we waited a good 45 minutes to make sure that there wasn’t so much as a nanometer of water lost from the tank.


Here is a couple quick pics of the D-Box replacement piece and what the more modern versions look like.

All said and done, this inspection for a sale was $245 for the inspection, $420 for the pumping and $700 for the Distribution Box.  $1365 before tax.  Not a bad inspection when it comes down to it! The nightmares caused by thinking of what could happen make that price tag an easy pill to swallow. Please note:  all inspections, all septic tanks, and all systems are completely different.  We just wanted to shine a little light into what’s happening down there. For a ‘fun’ read on septic ownership, here’s a blog post from a broker.   For all the Septic info you could possible flush, visit the King County Health Department.




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