Chimney Sweep Checklist: Everything Your Tech Should Inspect on Every Visit

By David Chimney Team · Updated July 6, 2026

A thorough chimney sweep checklist covers the firebox, liner, damper, smoke chamber, crown, flashing, and exterior masonry. For older Lynnwood homes with clay-tile liners and aging brick, techs should also probe for spalling, efflorescence, and mortar joint erosion on every single visit.

Why Older Lynnwood Brickwork Makes a Structured Checklist Non-Negotiable

A chimney sweep checklist is a systematic, point-by-point inspection protocol that a certified technician works through before, during, and after cleaning — ensuring nothing gets missed and every defect gets documented. In a generic new-construction home, that checklist might feel routine. In Lynnwood, WA, where a significant share of single-family housing stock dates to the 1950s through the 1980s, it is anything but routine.

Here is the reality we encounter week after week: older Lynnwood homes were built with clay-tile-lined chimneys and soft mortar mixes that simply were not engineered for modern high-efficiency wood inserts or natural-gas conversions. Snohomish County's wet winters — consistent rainfall from October through April — drive freeze-thaw cycling into every open mortar joint. A tech who skips even one line item on the checklist can miss early-stage liner cracking or mortar deterioration that, left alone, becomes a Category 2 or Category 3 repair by spring.

That is exactly why our inspections at David Chimney are built around a written checklist, not memory. Every technician on our team works the same sequence on every visit — whether we are in a 1962 ranch-style on 196th St SW or a 1978 split-level closer to Mountlake Terrace. If you want to understand the broader inspection framework we use, our guide to Lynnwood chimney and flue inspection levels lays out what separates a Level 1 from a Level 3 inspection and when each applies.

Inside the Firebox: The Checklist Starts Where the Fire Actually Burns

The firebox is the masonry chamber that contains the fire itself. Every sweep visit should begin here, because this is where combustion byproducts originate and where the first structural clues about liner and flue health appear.

Your tech should be examining:

**Firebox walls and floor:** Look for cracks in refractory panels or firebrick, spalling brick faces, and gaps in the mortar joints. In older Lynnwood homes, the original firebrick is often soft and porous — it absorbs moisture from our wet climate and begins to flake well before the exterior masonry shows any distress.

**Smoke shelf and smoke chamber:** The smoke shelf sits just above the damper and catches debris falling from the flue. It should be scraped free of hardened creosote and ash. The smoke chamber walls — the sloped surfaces that funnel combustion gases into the flue — should show no open cracks or missing mortar. Parged (smooth-coated) smoke chambers are standard; rough, corbeled masonry in older homes is a known draft problem and a creosote accumulation point.

**Damper plate and frame:** The damper should open fully, seal tightly when closed, and show no warping from heat stress or rust from condensation. A damper that does not seal completely is costing Lynnwood homeowners real money in heating loss every winter — not just a draft nuisance.

((The Chimney Safety Institute of America (CSIA)|https://www.csia.org/)) recommends inspecting the firebox and smoke chamber annually regardless of usage frequency, because moisture intrusion can cause structural changes even in a chimney that hasn't been used all season. Our complete guide to chimney sweeping in Lynnwood goes deeper on what to expect during this phase of the appointment.

Liner Integrity Is the Heart of the Checklist for Brick Chimneys Built Before 1990

A chimney liner is the protective channel — clay tile, cast-in-place, or stainless steel — that contains combustion gases and prevents heat transfer to the surrounding structure. In Lynnwood homes built before 1990, original clay-tile liners are the norm. They work adequately when maintained, but they are brittle, they crack at mortar joints under thermal cycling, and they were never rated for the flue temperatures produced by some modern wood inserts.

On every chimney sweep checklist, liner inspection is the most consequential item. A cracked liner is not a cosmetic issue. ((The National Fire Protection Association (NFPA)|https://www.nfpa.org/)), under NFPA 211, requires that chimney liners be maintained free of deposits and defects to safely contain products of combustion. A gap in the liner allows carbon monoxide, heat, and sparks to reach combustible framing materials — a genuine house-fire risk.

What should a tech actually check?

- **Visual scan from below:** With a good flashlight or inspection mirror, tiles should show no horizontal or stair-step cracking, no missing mortar at the tile joints, and no visible light penetrating the tile walls. - **Camera scan (for older homes):** Any Lynnwood home with a clay-tile liner that has not been scanned in the past three years — or ever — should have a CCTV video scan. Cracks that are invisible from the firebox opening show up clearly on camera. - **Appliance compatibility:** If the homeowner has recently installed a gas insert or a high-efficiency wood stove, the tech should confirm the existing liner size and condition are appropriate for the new appliance's BTU output and flue-gas temperature.

For a thorough breakdown of liner options and repair methods, see our chimney liner installation and repair guide for Lynnwood homeowners.

Exterior Masonry Checkpoints That Lynnwood's Rain Exposure Demands Every Year

The exterior masonry inspection covers everything visible from the roofline up — and in our climate, it deserves its own dedicated section of the checklist. Lynnwood sits in western Snohomish County and sees 35–40 inches of precipitation annually, most of it falling as steady, soaking rain that saturates brick and mortar far more thoroughly than the occasional downpour of drier climates.

Here is what every tech should be examining on the exterior:

**Crown:** The chimney crown is the concrete or mortar cap that seals the top of the masonry chimney chase, leaving only the flue opening exposed. It should overhang the brick and slope downward to shed water. Cracked or improperly sloped crowns are among the most common defects we document in Lynnwood — and among the cheapest to fix early versus expensive later.

**Flashing:** The metal flashing where the chimney meets the roof plane must be fully sealed and free of rust, lifted edges, or gaps. Failed flashing is a leading cause of attic water damage and interior wall staining in the older ranch-style homes common in neighborhoods north of Alderwood Manor.

**Brick face and mortar joints:** Spalling brick (faces popping off), efflorescence (white mineral staining), and eroded mortar joints are all signs that water is winning. Tuckpointing — grinding out deteriorated mortar and repacking with fresh mortar — is the repair; our masonry repair and tuckpointing guide for Lynnwood explains the process in detail.

**Cap and spark arrestor:** The flue cap keeps rain, birds, and squirrels out of the flue. The tech should confirm the mesh screen is intact and free of debris blockage — a crushed or missing cap in a Lynnwood winter is an invitation for a nest or water column.

If the exterior inspection turns up significant damage, contact us for a free estimate before the fall rainy season sets in.

Creosote Assessment: What Your Checklist Should Classify, Not Just Note

Creosote is the combustible, tar-like residue that condenses on the inner walls of the flue when wood-smoke gases cool before fully exiting the chimney. It is the primary fuel in chimney fires, and its removal is the core mechanical purpose of every sweep visit. But a professional chimney sweep checklist should not just note that creosote is present — it should classify it by degree, because the degree determines the cleaning method and the urgency.

**First-degree creosote** is a light, flaky soot that brushes away easily with standard rotary or hand brushes. Most homeowners who burn seasoned hardwood and use their fireplace moderately will see first-degree deposits.

**Second-degree creosote** is a crunchy, tar-flake deposit that requires chemical treatment before mechanical brushing. It is common in Lynnwood homes where the original clay-tile liner runs partially through an exterior wall — flue temperatures drop faster there, encouraging more condensation.

**Third-degree creosote** is a hardened, glazed coating that bonds to tile and steel. It is a serious fire hazard and typically requires specialized chemical rotary systems or, in severe cases, liner replacement. We see this most often in homes where a wood stove was operated with wet or green wood over multiple seasons.

The EPA's Burn Wise program consistently highlights that burning properly seasoned hardwood — moisture content below 20% — dramatically reduces creosote accumulation at all degrees. A good technician will note the current degree in writing on your service record, not just sweep and leave. That documentation matters when you are tracking maintenance history for a home sale or an insurance inquiry.

For more context on scheduling around creosote buildup, our year-round chimney maintenance calendar for Lynnwood homeowners maps out when to book and why.

What a Finished Sweep Report Should Hand You Before the Tech Leaves the Driveway

A professional sweep visit is not complete when the brushes go back in the van. The final item on a legitimate chimney sweep checklist is documentation — a written or digital report that captures every finding, every cleaned component, and every defect observed.

At minimum, the report you receive should include:

- **Service summary:** What was swept, what tools were used, and what degree of creosote was removed. - **Inspection findings:** Any cracked tiles, spalling brick, mortar defects, flashing gaps, or damper issues — noted with location specifics, not just "chimney needs work." - **Photos:** Any modern inspection should include at least a few images, particularly of any defects. A liner camera scan should produce video or stills you can keep on file. - **Recommendations and urgency rating:** Good techs distinguish between "monitor at next annual visit" and "do not use this appliance until repaired." That distinction matters for your safety and your insurance coverage. - **Technician credentials:** Verify the tech who signed off is CSIA-certified. Ask if you cannot tell from the paperwork.

If a company sweeps your chimney and hands you nothing in writing, that is a red flag — not a bargain. We explain our own service standards on our about page, and our full services menu breaks down what is included in each visit type.

We serve homeowners across the area — from Edmonds and Shoreline to Bothell and Everett — and we bring the same checklist discipline to every address. If you are wondering whether your current provider covers all of these points, it is worth a conversation. Reach out to schedule and we can talk through what your chimney actually needs.

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