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Selling A House With An Oil Tank In Seattle

The tank is almost never what kills the deal. The missing paperwork, found three weeks before closing, is.

Disclosed on
NWMLS Form 17
Permit before work
Always
Backdating
Not possible
Report to owner
30 days

What The Buyer’s Side Actually Asks For

Two documents, not a reassurance. The permit stamped Approved to Proceed, and the Heating Oil Tank Decommissioning Report Form that the certified decommissioner filed afterwards. A property owner is supposed to be holding both.

If you have them, the item closes in a day. If you do not, the buyer is looking at an undocumented tank, and undocumented is the word that generates a price adjustment.

Where Sellers Lose Time

Assuming A Clean Record Search Settles It

An empty result in the city’s tank data is not proof of absence, and a record that says fill in place is not proof the tank is gone. What the record proves is narrower than most people assume, and buyers’ agents know it.

Discovering It At Inspection

A fill pipe by the driveway or capped copper in the basement wall turns into a contingency item on someone else’s timetable. The same job arranged before listing is the same job without the deadline.

Hoping To Permit It Afterwards

The Seattle Fire Department will not issue a permit once the work has been performed. Work done quietly, by a previous owner or an uncertified contractor, cannot be regularized by paying the fee later.

Leaving It Off Form 17

Washington’s seller disclosure statement asks the question directly. An omission that surfaces after closing is a considerably more expensive conversation than a disclosed tank with a quote attached.

The Version That Goes Smoothly

Deal with it before the listing photos. Check what the city holds, confirm whether the address sits inside Seattle or in unincorporated King County, then permit and complete the work while nobody is waiting on it.

You list with the tank disclosed, the method stated and the report in the file. The buyer’s question gets answered before it is asked, and there is nothing left to negotiate against.

Buying Rather Than Selling

Ask for the same two documents, and read which method the report names. A removal closes the subject. A fill in place means the tank is still under the property, which is lawful and documented but not the same thing.

Where nothing exists at all, price the work rather than the fear. Removal and a compliant fill in place sit a long way apart on cost, and which one you need is usually decidable before you are under contract.

Common Questions

Do I have to disclose an oil tank when selling in Washington?
Washington sellers complete NWMLS Form 17, the seller disclosure statement, which asks about underground storage tanks. The tank does not go away by being left off the paperwork, it becomes a bigger problem later.
Will an oil tank stop the sale?
Rarely on its own. It slows things down when it surfaces during inspection with no record attached, because the buyer then has an open question and a deadline at the same time.
Should I decommission before listing or wait for the buyer to ask?
Before listing is cheaper and calmer. Once it is a contingency item you are negotiating under a clock, and the permit cannot be backdated to catch up.
The tank was dealt with years ago. Is that enough?
Only if you can produce the paperwork. What a buyer wants is the permit stamped Approved to Proceed and the decommissioning report. Without either, the work is undocumented regardless of what happened on site.
Can a decommissioning be done inside a normal closing window?
Usually, provided the permit goes in early. The permit has to be approved before the work, so the constraint is the front of the process rather than the digging.

There Is A Date In The Diary

Tell us the address and the closing date. You get a written quote and a realistic answer on whether the permit and the work fit inside the window.