Chimney Liners and Relining in Seattle

A liner is the tube inside the chimney that carries smoke and gases up and keeps heat away from the brick and the framing around it. In older Seattle and Tacoma houses it is usually clay tile, and in some of the oldest there is no liner at all. Tacoma has the oldest housing in the area, with about 27 percent built before 1940, and Seattle is close behind at about 23 percent.

Liners fail for ordinary reasons: tiles crack from a chimney fire or settling, joints open up, or a new appliance needs a flue of a different size than the old one. Earthquakes play a part here too. After the 2001 Nisqually quake, a University of Washington team catalogued about 60,000 chimneys from Bremerton to Mercer Island, and cracked chimneys do not always show it from the outside.

Signs you need this

• Pieces of clay tile falling into the firebox
• A new wood stove, insert or gas appliance going in
• A chimney fire, or a crackling roar from the flue
• Smoke or smell in rooms the chimney passes through
• An old oil furnace flue now serving a gas water heater

How we do it

1. See inside the flueThe free inspection is visual from top to bottom with photos. If a hidden crack is suspected, a camera scan is priced at the inspection.
2. Size it to the applianceWe match the liner's diameter to what it will serve, because a flue that is too big or too small drafts poorly and builds deposits.
3. Install from the topA stainless liner is fed down from the roof, connected at the bottom and fitted with a top plate and cap.
4. Test and photographWe check the draft, photograph the finished connection at both ends and write it on your report.

Stainless steel or cast-in-place?

A stainless liner is a steel tube run down the existing flue. It is the usual choice for wood stoves, inserts and gas appliances and typically costs $1,500 to $5,000. A cast-in-place liner is a cement mix poured around a form inside the chimney. It also adds some strength to old brick and typically costs $2,000 to $7,000. Which one fits depends on the shape of the flue, how many bends it has and what it will vent.

Does my furnace or water heater need a liner?

Often, yes. Seattle still has about 2.9 percent of homes on oil heat and Shoreline about 4.1 percent, and many more switched away from oil and left an old flue behind. When a furnace is replaced and a gas water heater is left alone in a big masonry flue, the gases can cool before they reach the top and leave moisture inside the chimney. A correctly sized liner for that appliance typically costs $625 to $2,250.

Is a permit needed?

That depends on the city and on what the liner serves. Seattle's SDCI issues mechanical permits for new heating and venting equipment, Bellevue requires a permit for inserts and pellet stoves, and unincorporated King County requires one when a fireplace or wood stove is installed or replaced. We tell you at the inspection which office covers your address so the work can be scheduled around the inspection.