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CHIMNEY INSPECTION DIAGNOSIS REPAIR
Abandoned Chimneys - Indoor Inspection
Abandoned Chimneys: Outdoors
Angled Chimney Flues
ARCHITECTURE & BUILDING COMPONENT ID
Attic Chimney Inspection
BACKDRAFTING HEATING EQUIPMENT
Blocked Chimney Flues
Bracket Chimney Collapse & Fire Risks
B-Vent Clearances Table
CARBON DIOXIDE - CO2
CARBON MONOXIDE - CO
CHIMNEY CAP & CROWN
CHIMNEY CHASE Construction & Defects
Chimney Cleaning Advice, Procedures
Chimney Cleaning Fraud Warning
CHIMNEY CLEANOUT DOORS
Chimney Components Definitions
CHIMNEY COLLAPSE Risks, Repairs
Chimney Crack Detection & Diagnosis
Chimney Draft & Performance
CHIMNEY FIRE ACTION / PREVENTION
CHIMNEY FLASHING Mistakes & Leaks
CHIMNEY HEIGHT & CLEARANCE CODE
Chimney Height Extensions
Chimney Inspection Checklist
Chimney Inspection: Flue Interiors
CHIMNEY INSPECTION CAMERA
Chimney Inspection Indoor Procedures
Chimney Inspection Outdoors From Ground
Chimney Inspection Outdoors at Rooftop
Chimney Leaning, Separation, Movement
Chimney Repair Fraud Warning
Chimney Repair Methods
CHIMNEY SAFETY - CPSC Alert
CHIMNEY SHOULDER LEAKS
CHIMNEY SHROUD, Decorative
CHIMNEY STAINS & LEAKS
Chimney Types & Materials
COMBUSTION AIR DEFECTS
COMBUSTION AIR for TIGHT buildings
COMBUSTION GASES & PARTICLE HAZARDS
COMBUSTION PRODUCTS & IAQ
COMPLETE COMBUSTION, Stoichiometric
CREOSOTE FIRE HAZARDS
Curved Brick Chimneys - Sulphation
Dead End Chimney Flue Hazards
Definitions of Chimney Types & Parts
DIRECT VENTS / SIDE WALL VENTS
DRAFT HOODS - gas fired
DRAFT MEASUREMENT, CHIMNEYS & FLUES
DRAFT REGULATORS, DAMPERS, BOOSTERS
EFFLORESCENCE, Salts & White / Brown Deposits
EMERGENCY RESPONSE, IAQ, GAS, MOLD
FIRE CLEARANCES INDOORS
Fire Clearances for Masonry Chimneys
Fire Clearances for Metal Chimneys
FIRE CLEARANCES, Single-Wall Metal Flues
FIRE CLEARANCE WOOD & COAL STOVE FLUES
FIREPLACES & HEARTHS
FIRE STOPPING in BUILDINGS
FLAME COLOR, BLUE vs YELLOW COMBUSTION
FLASHING, CHIMNEY Mistakes & Leaks
FLUE SIZE SPECIFICATIONS
Flue Separation Requirements
Flue Tile Damage in Chimneys
Flue Vent Connectors - Boilers, Furnaces
Fuel Changes for Heating Appliances
HEATING COST FUEL & BTU Cost Table
HOME HEATING SAFETY
INDOOR AIR EMERGENCY RESPONSE
Lennox SAFETY WARNING
Metal Chimneys & Flues
Moisture / Frost Damaged Chimney
NOISE / SOUND DIAGNOSIS & CURE
ODORS & SMELLS DIAGNOSIS & CURE
ODORS FROM HEATING SYSTEMS
OIL HEAT SAFETY INSPECTIONS
PLASTIC HEATER VENTS
ROOF STAINS from CHIMNEYS
Safety Recalls, Chimneys, Vents, Heaters
Shared Chimney & Shared Flue Hazards
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAINS on/near CHIMNEYS
Three-Sided Chimneys: Problems
Transite Pipe Chimneys & Flues
UNLINED FLUE INSPECTIONS
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
This article describes how to select, install, and inspect Class-A insulated metal chimneys such as the Insulated Double Wall MetalBestos™ manufactured metal chimney, also called a zero clearance chimney. These articles on chimneys and chimney safety provide detailed suggestions describing how to perform a thorough visual inspection of chimneys for safety and other defects. Chimney inspection methods and chimney repair methods are also discussed.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Improper metal chimney installation: As you can see from our photo ( above left), even this superb product can be reduced to shambles when installed by an idiot. The chimney in this photo was not supported, is falling and is unsafe. See Chimney Collapse Hazards & Chimney Support & Bracing Requirements.
This unfortunate collapsing Class-A type metal chimney was the replacement for the abandoned masonry chimney under the corrugated metal roof we show at Chimneys Abandoned Outdoors and that whose remains we showed at Chimneys Abandoned Indoors. It looks as if more than one generation of inexpert chimney installers worked in Dover, NY.
Our photo at above right shows an end view of a section of Metalbestos SS All Fuel Chimney™. The fiberglass insulation is not part of the product and was just left stuffed in that opening.
Class A Chimney Height Requirements
More complete details about chimney height requirements on buildings including Class A Chimneys is at CHIMNEY HEIGHT & CLEARANCE CODE
Class A Chimney Fire Clearance Details
More complete details about Class-A chimney fire clearances indoors can be read at Fire Clearances for Metal Chimneys
Should an Insulated or "Air Cooled" Metal Chimney Be Replaced After a Chimney Fire has Occurred?
Question: What Kind of Inspection Is Required After a Metal Chimney Fire?
I was looking for information on chimney fires, specifically, on how to inspect double wall pipe after such an event. The outside of the outer pipe had paper stickers on it that were not burnt or discolored, so I am assuming the pipe did its job. However the top of the chimney run did catch on fire, presumably from the heat generated from the chimney fire. Anyway, I was looking for a category on how to inspect double wall pipe after a fire. - K.M.
Reply: Inspect for visible flue damage, color changes, movement, cracks; but to be safe: in our opinion you should replace the chimney
After a chimney fire (such as from igniting creosote in a metal flue), a competent onsite chimney inspection by an expert usually finds additional clues that help accurately diagnose a problem. That said, we add the following opinion:
In sum: in our opinion after a chimney fire in an insulated metal chimney or an air-insulated metal chimney the chimney should be replaced entirely in order to be safe and to assure that maximum fire protection for the building is maintained. In addition you should inspect for heat or fire damage to surrounding building components. Details follow.
Some chimney repair companies and building codes cite that "metal chimneys must be inspected after a fire for possible need for replacement". We speculate that the chimney inspector will look for deformed, cracked, metal components, movement, color changes in the stainless steel, or signs of overheating or damage to surrounding building components.
If the metal chimney liner and metal exterior of a multi-wall insulated metal chimney are undamaged, one might think that the internal chimney insulation of a multi-wall insulated metal chimney or flue was intact. But that may not be true. In addition there may be subtle damage to surrounding building components such as pyrolysis (discussed at Fire stopping at Chimney Passage Through Floors) that could lower the combustion point and increase the risk of a future fire in nearby wood materials. Some sources point out that
We have observed steel flues that turned blue and also black after a fire.
A "be safe" approach requires that insulated chimneys are replaced after a fire.
We believe that this makes sense because because during a chimney fire the internal temperatures can be extremely high and thus can damage the flue in both obvious and less obvious ways that may not be visible and no one wants to take a chance.
Furthermore, the "after 900 degrees" rule is impractical: - who is actually measuring chimney temperature during a fire? The 900 degF number in our OPINION is not helpful.
Most chimney sources point out that it's common for a chimney fire to reach 2000 degF! Who wants to risk an unsafe flue after a fire when a new fire could still occur and could meet less protection.
A similar example is with earthquake-resistant construction: the construction is designed to keep the building from collapsing and killing the occupants, but it is not expected to prevent any damage whatsoever to the building. So after a quake repairs are going to be needed.
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