Fast, Reliable Chimney Cleaning & Sweep Across San Lorenzo
A typical chimney cleaning and sweep in San Lorenzo runs $189-$349 for standard service, with Level 2 camera inspections ranging $279-$425 depending on access and condition. Most San Lorenzo appointments are completed in a single visit, and our technicians carry the parts and equipment to handle Bohannon-era chimneys on the spot. Call (855) 408-5567 to reach a live person, any hour, any day.
We’ve been driving out to San Lorenzo since 1984, long before the 238 freeway connected the way it does now. Our trucks roll through the flat grid of Bohannon streets, past the old commercial strip on Hesperian Boulevard, and up to the stucco homes on Via Alamosa, Via Del Rey, and throughout the 94580 ZIP. We know these chimneys. Same age. Same construction. Same problems showing up on the same blocks, year after year. That repetition is not a burden for us. It means we arrive prepared, with the right tools and the right materials, and we do not waste your morning guessing.
San Lorenzo’s chimneys are not like Castro Valley’s hillside installations or the newer builds pushing toward Dublin. They’re 70-year-old masonry fireplaces in modest single-story homes, most never professionally cleaned, many with original clay tile liners that have seen every winter since Harry Truman was president. Our Chimney Cleaning & Sweep team treats that heritage with respect, and with the honesty to tell you when a sweep will suffice and when the chimney has reached the end of its safe service life.
Why Hearthstone Chimney Co. of San Francisco Is San Lorenzo’s Preferred Chimney Cleaning & Sweep Company
Forty-two years in this trade means we’ve swept chimneys in San Lorenzo through three generations of ownership in some of these homes. The grandson who inherited his grandmother’s house on Via Del Rey calls us because she did. That continuity matters in a town where people stay put.
Our Level-2 camera inspections end with photographs you can see and a plain-English verdict, documented like an engineer, explained like a craftsman. No jargon, no scare tactics. If your chimney is sound, we say so. If it needs work, we show you exactly where and why.
A live person answers our phones 24 hours a day, 7 days a week. Not voicemail, not a callback queue, not an app. Someone who can dispatch a technician to San Lorenzo, confirm your appointment, and answer a question about what to expect. Warren Eckhart built this standard into the company from the start, and we have not relaxed it.
Our 90-Day Done Right Promise governs every job: Krafted right, Every time, Your home first, Standing behind it. In writing. No arguing. If it’s not right, we come back.
Our Chimney Cleaning & Sweep Services in San Lorenzo
Level 1 Inspection
A Level 1 inspection is the visual examination required annually for chimneys in regular service. In San Lorenzo, we perform these during routine sweeps, checking accessible portions of the fireplace, chimney structure, and flue for obstructions, creosote buildup, and obvious deterioration. For Bohannon homes with no record of prior professional attention, this basic inspection often reveals the first signs of trouble: a cracked firebox, a stuck damper, or mortar joints turning to sand. We document what we find and explain what it means for safe operation.

Level 2 Inspection
Level 2 inspections are our most requested service in San Lorenzo, and for good reason. This is the camera inspection, performed with a high-resolution chimney scan that lets us see inside the flue, up into the smoke chamber, and around the damper assembly where human eyes cannot reach. For 1940s chimneys with original clay tile liners, this is where we find the vertical cracks at the smoke chamber transition that repeat block after block in this planned community. We photograph everything. You see what we see. Then we give you a plain-English verdict on whether the chimney is safe to use, needs repair, or has reached the end of its service life.

Creosote Removal
San Lorenzo’s mild winters encourage a particular firing pattern: a few low-temperature burns on foggy evenings, never hot enough to fully combust the volatile compounds in wood smoke. That pattern deposits glazed creosote, the hard, tar-like residue that chimney fires feed on. Our technicians use professional-grade rotary cleaning systems and, where necessary, chemical treatments to break down heavy buildup. We do not leave until the flue is clean to NFPA 211 standards. For homes that burn only occasionally, we often find creosote levels that surprise homeowners who assumed light use meant light buildup. The opposite is true in San Lorenzo’s climate.

Soot Removal
Soot accumulation is the gentler cousin to creosote, but it still reduces draft efficiency, stains interior surfaces, and can harbor acidic moisture that attacks masonry from the inside. During a full fireplace cleaning, we remove soot from the firebox, smoke shelf, and accessible flue passages, then inspect for the efflorescence and moisture staining that Bay-area humidity promotes. A clean chimney draws better, smells better, and gives you an honest view of the masonry condition beneath the grime.

Annual Sweep
For San Lorenzo homeowners who use their fireplaces even modestly, an annual sweep is the baseline of responsible maintenance. We schedule these throughout the burning season and into spring, when marine moisture is heaviest and the damage it causes is most visible. Our technicians arrive in uniform, background-checked, with the equipment to complete most jobs in a single visit. No-hassle upfront pricing means the number on the estimate is the number on the invoice.

Fireplace Cleaning
Beyond the flue, the firebox, hearth, and surrounding masonry need attention too. We clean ash pits, reset displaced firebrick, and assess the condition of throat dampers that have not moved freely since the Eisenhower administration. In San Lorenzo, stuck dampers are nearly as common as cracked liners. We can free them, repair them, or replace them with modern assemblies that seal properly when closed.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in San Lorenzo
We stock and install professional-grade materials from the manufacturers that serious sweeps rely on: Gelco caps and dampers, Olympia Chimney liner systems, Famco venting components, and Copperfield repair products. For San Lorenzo’s aging chimneys, we keep DuraFlex stainless steel liner kits on our trucks, sized for the narrow flues common in Bohannon construction. That inventory means we do not order parts and make you wait. Most liner installations, crown repairs, and damper replacements are completed same-day. We do not use builder-grade substitutes. The job is done right, or Warren Eckhart would not let us sign his name to it.
Common Chimney Cleaning & Sweep Problems We See in San Lorenzo Homes
- Original clay tile liners cracking at the smoke chamber transition. Because Bohannon homes were built from nearly identical blueprints, this defect repeats with remarkable consistency. Our technicians can predict what the next three houses on a block will need before setting up a ladder. The vertical crack allows combustion gases to leak into chimney walls, accelerating mortar decay and creating carbon monoxide risk.
- Mortar crowns failing from decades of marine moisture exposure. San Lorenzo’s proximity to the Bay means persistent fog and humidity that erodes crown mortar, exposing the brick beneath to accelerated freeze-thaw damage. A compromised crown lets water into the chimney structure, where it destroys liners, rusts dampers, and damages interior finishes.
- Heavy creosote buildup despite infrequent use. Mild winters encourage low-temperature fires that never reach the sustained heat needed to burn creosote clean. The result is rapid accumulation that surprises homeowners who burn only occasionally. This glazed creosote is the most dangerous variety, igniting at lower temperatures and burning with explosive intensity.
- Stuck or corroded throat dampers in original 1940s fireplaces. Decades of disuse, combined with moisture and creosote corrosion, leave these dampers frozen open or closed. A stuck-open damper wastes heated air up the flue year-round. A stuck-closed damper prevents fireplace use entirely or forces smoke into the living space.
Pricing for Chimney Cleaning & Sweep in San Lorenzo, CA
Honest pricing for San Lorenzo’s market, based on what we have charged here for over four decades:
| Service | Typical Range in San Lorenzo |
|---|---|
| Standard chimney sweep (Level 1 included) | $189 - $279 |
| Level 2 camera inspection | $279 - $425 |
| Heavy creosote removal (glazed buildup) | $325 - $495 |
| Fireplace cleaning with damper service | $245 - $375 |
| Annual maintenance plan (sweep + inspection) | $149 - $199/year |
What moves the price: accessibility of the chimney (steep roof pitches are rare in San Lorenzo’s flat terrain, which keeps costs down), severity of creosote buildup, whether the flue is obstructed by nests or debris, and the condition of components that need repair or replacement. We provide upfront pricing before any work begins. The number on the estimate is the number on the invoice. Call (855) 408-5567 for a free estimate with no obligation.
Standing offers: $50 off any repair over $250; free second opinion on any written estimate; $89 seasonal tune-up; permanent 5% senior and veteran discount.
We Also Serve Cities Near San Lorenzo
Our trucks cover the full corridor from San Lorenzo through Ashland, San Leandro, Cherryland, and Castro Valley. The same marine climate, the same aging housing stock, the same honest assessment and upfront pricing apply in every town we serve. If you are just outside the 94580 ZIP, call anyway. We likely already have a technician in your neighborhood.
Serving San Lorenzo, CA - Our Local Coverage Area
We’re based in the San Lorenzo area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Chimney Cleaning & Sweep in San Lorenzo
Most 1947 chimneys in San Lorenzo need a stainless steel liner if the original clay tile is cracked, which it usually is. On Via Alamosa, we swept a 1948 Bohannon home where the original clay tile liner had a vertical crack at the smoke chamber junction, a defect we see on every block here. We used a DuraFlex stainless steel liner to restore safe function, avoiding a full chimney rebuild. A Level 2 camera inspection will tell you definitively. Call (855) 408-5567 to schedule one; estimates are free.
Moss grows on San Lorenzo chimneys because of persistent marine fog and humidity from the nearby Bay, combined with porous brick that has absorbed moisture for 70-plus years. The moss itself is a symptom, not the disease. It indicates a failed or failing mortar crown, deteriorated pointing, or saturated brick that will not survive many more freeze-thaw cycles. We remove the moss, repair the underlying moisture intrusion, and seal or rebuild the crown with professional-grade materials. Call for an inspection and we will show you exactly where the water is getting in.
In San Lorenzo, infrequent low-temperature fires actually produce more dangerous creosote buildup than regular hot burns, so annual sweeping is still recommended even for light use. The NFPA 211 standard calls for annual inspection, with cleaning as needed. Most of our San Lorenzo customers who burn occasionally still need yearly creosote removal. Mild winters are no protection; the firing pattern matters more than the calendar. Schedule your annual sweep and we will measure the buildup so you know where you stand.
Yes, we free, repair, and replace stuck dampers in original 1940s San Lorenzo fireplaces as a routine part of our service. Corrosion, creosote cementing, and decades of disuse are the usual culprits. Sometimes the damper can be restored to function with cleaning and adjustment. Other times, the throat assembly is too far gone and we install a modern replacement that seals properly and operates smoothly. We will show you the condition and give you both options with upfront pricing.
A 70-year-old chimney in San Lorenzo can be safe to use if it has been properly maintained, but most have not been, and hidden damage is common. The only way to know is a Level 2 camera inspection that examines the flue interior, smoke chamber, and damper assembly for cracks, gaps, and deterioration. We have condemned chimneys that looked fine from the outside and cleared others that homeowners assumed were hopeless. The inspection takes about an hour, the photos are yours to keep, and the estimate is free. Call (855) 408-5567 to book.
Written by Warren Eckhart, Owner at Hearthstone Chimney Co., serving San Lorenzo since 1984.