Should you remove an unused chimney in Seattle?

Seattle Fireplace & Chimney · October 14, 2026

Why people take them down

Many Seattle houses have a chimney that has not seen a fire in years. The house switched to an electric heat pump or baseboard heat, the oil furnace was pulled out, or the fireplace was closed off. Census data (American Community Survey, 2020 to 2024) shows about 61 percent of Seattle homes now heat mainly with electricity. The chimney is still there, catching rain and standing above the roof.

There are two reasons to remove one. The first is earthquakes. FEMA's guide to nonstructural earthquake damage (E-74) says unreinforced masonry chimneys are extremely vulnerable and may be damaged even at relatively low levels of shaking, and it names removal and replacement with a metal flue in a framed enclosure as the most reliable fix. The 2001 Nisqually earthquake showed the risk: a University of Washington and USGS survey of about 60,000 chimneys found damage concentrated in West Seattle along the Seattle Fault.

The second is upkeep. An unused chimney still needs flashing, a crown and sound mortar, or it leaks. Removing it ends that cost.

First, check what it vents

Seattle's chimney repair rule, Director's Rule 5-2004, includes a specific warning: a chimney may also be venting a gas water heater. Many older houses have a second flue inside the same brick stack for the furnace or water heater, even when the fireplace flue is unused. Seattle still has about 2.9 percent of homes on fuel oil, and Shoreline 4.1 percent, so old oil-furnace flues are common.

If an appliance still vents through the chimney, the stack cannot simply come down. The appliance needs a new vent, or the chimney keeps a lined flue. A furnace or water heater liner typically runs $625 to $2,250.

How much to take down

Removal is not all or nothing. There are three common levels, and the right one depends on the house, the roof and what you want inside.

• Cut down to 1 to 2 feet above the roof. FEMA E-74 notes an unused chimney can be shortened this way, which removes most of the weight that can fall in an earthquake.
• Remove the stack down below the roofline, then patch the roof. Typically $1,000 to $2,500.
• Remove the stack and the chimney breast inside the house, which frees up floor and wall space. Typically $4,000 to $10,000.

Seattle rules to know

DR 5-2004 covers alterations and repairs to unreinforced chimneys. Work that goes below the top of the smoke chamber triggers a full rebuild requirement and a building permit, and work under $4,000 needs no permit but must still follow the rule. How a partial removal is treated depends on the scope, so confirm current requirements with Seattle's Department of Construction and Inspections (SDCI) before the work is scheduled. One of the rule's options is relevant if you want to keep a fireplace: everything above the smoke chamber can be replaced with a listed metal chimney, which may be enclosed in a framed chase.

If the house is in one of Seattle's eight historic districts, such as Harvard-Belmont, removing or shortening a chimney changes the exterior, and the city says exterior changes need a Certificate of Approval even when no permit is needed. Call the Historic Preservation Program at (206) 684-0228 first.

What happens to the roof and the house

A good removal is mostly about what is left behind. The roof opening needs framing and sheathing that match the rest of the roof, with new underlayment and shingles woven in, so the patch does not become the next leak. Inside, a removed breast leaves floor and ceiling openings to frame and finish. If only the top comes off, the remaining stack needs a sound cap so water does not go down the old flue.

Brick and mortar come down by hand and go out in buckets or a chute. It is dusty work, and the area under the chimney is protected first.

Keep it or take it down

If you still use the fireplace, removal is not the answer; reinforcement, a partial rebuild, or a metal chimney above the smoke chamber is. Typical ranges there are $1,000 to $3,500 for the top few courses and $5,000 to $15,000 or more for a full rebuild above the roofline. If you never use it, removal usually costs less over time than keeping it watertight.

Our inspection is free. We check what the chimney vents, look at it top to bottom, take photos and give you a written price for each option before any work. Overall, chimney removal typically runs $1,000 to $10,000.