Booking a chimney sweep in Kirkland starts with what you own

Kirkland's housing sits in a narrow window: of roughly 41,910 units, 10,541 went up between 1970 and 1979 and another 7,039 between 1980 and 1989, and the median unit dates from 1985. Those are the decades in which factory-built fireplace systems were widely installed in new construction, which is why a cleaning here is as likely to be metal work as brick work.

• Look at the firebox walls. Brick in courses with mortar joints between them is masonry. Smooth panels with straight seams, inside a metal surround, are the refractory panels of a factory-built unit.
• Look up past the damper. A square or rectangular clay tile is a masonry flue. A round metal pipe, usually double or triple wall, is a listed factory-built chimney.
• Look outside, then find the label. A brick stack running to the ground is masonry; a sided box closed on top with a sheet-metal cover is a chase. Factory-built systems also carry a manufacturer's label, often just inside the firebox opening, and the make and model decide which parts are the right parts.

The yearly interval belongs to the inspection, not to the cleaning. Under NFPA 211 a chimney, fireplace or vent is looked at once a year to confirm it is sound, clear of deposits and correctly separated from combustibles, with cleaning and repair following from what that finds. Whether the flue needs sweeping in any given year is then a measurement, not an assumption.

How fast a Kirkland flue gets there is not purely a matter of how cold the winter was. Kirkland is in King County, so Puget Sound Clean Air Agency burn bans apply, and during a Stage 1 ban a wood-burning fireplace and any uncertified stove or insert has to stay cold. Ban days deposit nothing, which is why two neighbours with identical fireplaces end up on different intervals.

Two things push the other way. Creosote forms when wood smoke condenses on the cooler inside walls of a flue, and it builds fastest with restricted air, unseasoned wood, an overloaded firebox and a chimney running cold. An exterior stack on the weather side of the house, through a December recording rain on 20 to 25 days or more, is exactly that.

Kirkland is not flat. The ground climbs away from the water at Moss Bay, Lakeview and Central Houghton up onto Rose Hill, the Highlands and Finn Hill, and a lot dropping steeply toward the lake can leave a single-story roof two stories above the downhill grade. The roof is usually wet as well: regional normals record about 156 days a year with measurable precipitation and roughly three quarters of the annual total between October and March, and moss on a shaded winter slope is slick underfoot.

• Let the fireplace go fully cold, and clear the hearth. A day without a fire, longer after a hard run, and the mantel and hearth cleared. Containment goes down before anything is opened, and nothing is opened over live embers.
• Describe how the property is reached. A gate code, a shared lakeside lane, a steep or narrow drive, or street parking that works on only one side all change how the day is staged.
• Settle who approves the work. The median renter-occupied unit here dates from 1992, and in a rental, a condominium or an association-managed community the roof, the chase and the flue are frequently not the occupant's to open.

Sweeping removes deposits. On its own it does not answer the four questions that most often sit behind the call.

• You are selling, or you have just bought. Sale or transfer is a Level II inspection circumstance under NFPA 211, and a Level II includes an image scan of the flue liner. That is the booking to make; a cleaning may be what it then calls for.
• Water is showing up indoors. Rust on the damper, dripping in the firebox and bent flashing are water findings, not soot findings. They are traced from the top down, at the crown or the chase cover.
• The mortar or the brick is coming apart. Eroded joints and flaking brick faces are masonry work. A cleaning neither causes them nor corrects them.
• You are adding or changing an appliance. That raises liner size and material questions, and puts the chimney into Level II territory under the standard.

Anything found during a cleaning that turns into work comes back as a written scope and price before it starts. In Kirkland the permit question belongs to the City's own Development Services and to the codes adopted under Title 21 of its municipal code — not to any Seattle agency — and the answer turns on your property and your scope, so put it to the City first.