HEATING SYSTEMS
THERMAL TRACKING
What is Thermal Tracking
Ceiling Thermal Tracking Marks
Wall Thermal Tracking Stains
Floor Carpet Thermal Tracking Stains
Air Bypass Leaks Marks on Insulation
Thermal Tracking to Diagnose IAQ
Stains HVAC Supply Registers
Pet Stains on Walls
Human Occupant Stains on Walls
Stains from Candles, Woodstoves, Fireplaces
Other Stains on Indoor Walls & Ceilings
What to Do About Thermal Tracking
STAIN DIAGNOSIS on Indoor Surfaces
PHOTO GUIDE TO STAINS on Indoor Surfaces
CARPET TEST GUIDE
also see Investigation of Indoor House Dust Debris
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Thermal Tracking: How to Diagnose Indoor Ceiling Stains & Building Air Leaks
InteriorAPedia ©
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- What causes those dark stains on building interior ceilings? Photos & text identify thermal tracking, thermal bridging, air bypass, insulation defects and air movement in buildings
- How to recognize poorly insulated building walls or ceilings and how to pinpoint building air leaks
- A photo-guide to common indoor ceiling and wall stains and what they mean
- Links to more photos of indoor ceiling or wall stains that are not toxic mold
Our site offers impartial, unbiased advice without conflicts of interest.
We will block advertisements which we discover or readers inform us are associated with bad business practices,
false-advertising, or junk science. Our contact info is at
inspect-ny.com/appointment.htm.
This article describes how to identify and diagnose ceiling stains in buildings
focusing on the cause of various interior wall and ceiling stains and explains how to recognize thermal tracking, thermal bridging stains,
building air leaks, and building insulation defects. Often these stains are mistaken for toxic indoor mold.
Our page top photo shows two common thermal tracking or "ghosting" patterns. The narrow dark stains on the ceiling show the location of ceiling joists, and the wide black sooty stain in the upper left of the photo shows where ceiling insulation is less or has been omitted entirely.
When investigating a building for a mold problem, you can save mold test costs by learning
how to recognize Stuff that is Not Mold or is only Harmless Mold but may be mistaken for more serious contamination.
© Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
Building Air Leaks & Thermal Tracking Marks at Interior Ceilings
Sooty or dark smudges or stains appearing near the ceiling on the inside of building exterior walls, especially in older homes whose interiors have not been re-painted or cleaned in some time.
Thermal tracking stains may appear at the top of the wall and extend onto the ceiling surface such as shown in this photograph.
Note those dark "stripes" extending along the ceiling and into the room? These ceiling stains probably mark the location of ceiling joists (where the in-room ceiling surface temperature was kept a bit cooler since these locations
in the ceiling cavity are occupied by a wood joist rather than by insulation).
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Thermal tracking or "soot tracking" such as shown in the
photograph at the top of this page may be found wherever moisture condenses on cool building surfaces.
Warm moisture-laden air touches the cooler surface of a building wall or ceiling, giving up some of its moisture to the surface as condensation.
As air moves
through the building, typically up walls and across ceilings, debris in the air, particularly soot such as that left by burning
candles (scented candles may be more of an IAQ issue), adheres more to the damp surfaces than to others, leaving black marks or "tracks."
In a conventionally-framed
wood structure, wall and ceiling framing is typically on 16" or 24" centers.
The wall or ceiling interior surface will be cooler where the
framing is located than will be the spaces which are not touched by framing and which, perhaps, are insulated. So if you see
black streaks up the building wall in a regular 16" or 24" pattern, particularly on cooler exterior walls but potentially anywhere,
it may be thermal tracking.
Diagnosing Stain Patterns on Cathedral Ceilings
Cathedral Ceiling Stains: Alan Carson, a home inspection educator and researcher, points out that on cathedral ceilings,
where we see dark streaks following exterior studs or roof joists, (on cathedral ceilings very often), this is often associated with condensation
on the wall or ceiling surface, and dirt in the air sticking to the condensation. When the condensation dries, you just have the dirt following
the stud or joists lines. In the upper left section of our photograph below you can see stains marking the location of ceiling joists.
Ceiling stains over lights: Alan Carson adds that
we also see dirt marks on ceilings above light bulbs from chandeliers or other light fixtures using incandescent bulbs. For
example, if there are five candelabra type bulbs on a chandelier, we will often see five dark rings on the ceiling above. These relate to airborne
dirt being thrust against the ceiling as a result of the thermals that are created by the heat of the light bulb.
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Black rectangular stains on ceilings: that are about the width between ceiling joists are likely to mark areas where insulation has been reduced or omitted entirely - as you can see in our page top photo.
In a cathedral ceiling in which older recessed lights have been installed, you may see a combination of patterns:
- black rectangular stains around the ceiling light (insulation was kept several inches away from the light for fire safety), and
- white rectangular areas of "no stain" in sections of ceiling between the recessed lights (where an insulation batt was installed, but spaced away from the lights).
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Ceiling stains where insulation has been omitted completely: may be very apparent such as this photograph taken in a garage.
The garage ceiling was insulated except along one side where you see the long dark rectangular stain. This side of the garage was also an outside wall.
In a damp garage we might find mold growth on this area. |
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
THERMAL TRACKING
What is Thermal Tracking
Ceiling Thermal Tracking Marks
Wall Thermal Tracking Stains
Floor Carpet Thermal Tracking Stains
Air Bypass Leaks Marks on Insulation
Thermal Tracking to Diagnose IAQ
Stains HVAC Supply Registers
Pet Stains on Walls
Human Occupant Stains on Walls
Stains from Candles, Woodstoves, Fireplaces
Other Stains on Indoor Walls & Ceilings
What to Do About Thermal Tracking
STAIN DIAGNOSIS on Indoor Surfaces
PHOTO GUIDE TO STAINS on Indoor Surfaces
CARPET TEST GUIDE
also see Investigation of Indoor House Dust Debris
Technical Reviewers & References
Particular thanks are due to experts and also consumers who read these articles and suggest corrections, changes, and additions to
the material. Content suggestions, technical corrections and content critique are invited for any of the content at our website.
- Daniel Friedman - InspectAPedia.com TM Website Author/Editor
- Thanks to Alan Carson, Carson Dunlop, Associates, Toronto, for technical critique and content suggestions regarding thermal tracking.
- We welcome more thermal tracking, soot tracking, air bypass leaks, and similar photos of indoor stains as well as text suggestions to expand this detail and would be glad to credit contributors.
- Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
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WHAT MOLD LOOKS LIKE
MOLD IN HOMES
USING LIGHT TO FIND MOLD
MOLD BY MICROSCOPE
STUFF THAT IS NOT MOLD
DIAGNOSE OTHER DARK STAINS on Indoor Surfaces
PHOTO GUIDE TO STAINS on Indoor Surfaces
CARPET TEST GUIDE
Investigation of Indoor House Dust Debris
More Information
InspectAPedia TM Home & Site Map
Air Conditioning
InspectAPedia Bookstore
Electrical
Environment
Exteriors
Heating
Home Inspection
Insulate Ventilate
Interiors
Mold Inspect/Test
Plumbing Water Septic
Roofing
Structure
Accuracy & Bias Pledge
Contact Us
|
More Information on Finding and Identifying Mold in Buildings and Building Diagnostic Inspections and Repairs
- Attic Condensation and Ice Dam Leaks - Detection and Correcting Venting and Condensation Problems in Buildings
- Insulation Inspections: Insulation in Buildings: Identification, R-values, Heat loss, Insulation Types, Insulation Characteristics
- Asbestos pipe insulation in buildings
- Brick "Insulation" in Building Walls
- Heat Loss Calculations, Insulation Properties, Definitions of R, K, U values, Insulation Design
- How to Detect and Correct Attic Condensation & Prevent Ice Dam Leaks in Buildings
- Insulation Materials as Indicators of Building Age
- Indoor Air Quality Investigations: Fiberglass in Indoor Air, HVAC ducts, and Building Insulation
- Insulation Identification Photographs - Fiberglass insulation photos, yellow, pink, green, white fiberglass identification in building attics, walls, ducts, other locations
- Insulation Identification Photographs - Cellulose insulation photos, Mineral wool insulation photos, rock wool insulation photos, cotton insulation photos, balsam wool insulation photos
- Insulation Identification Photographs - Vermiculite insulation photos
- Insulation Properties, Table of R-Values, density, moisture permeability, fire safety, aging effects on various insulation materials
- Mold in Fiberglass in Insulation
- Radiant Heat Floor Mistakes to Avoid case history of improper placement of slab insulation and radiant heat tubing
- Thermal Tracking thermal bridging & air leak stains in buildings or on building insulation
- Un-Vented Roof Solutions - How to Prevent Attic Condensation, Ice Dam Leaks, Roof Mold, & Roof Structural Damage in Buildings with Un-vented Roof Cavities
- Vermiculite Building Insulation & Asbestos
- Ice Dam Leaks in building attics and roof cavities, how to inspect for evidence of leaks, identify causes, and correct bad attic ventilation, improper roof venting, and these causes of attic mold or roof structure damage
- Looking for Mold what mold is often found where in buildings - simple technical presentation
- Mold spores in the Home - a Photo ID Library for detection and identification of mold allergens
- Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
- Stuff that is not mold but is often mistaken for it - things you may not want to test. Also, not all "black mold" is toxic - here are examples of harmless black mold.
- Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
The Mold Information Center: What to Do About Mold in Buildings, When and How
to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems
Use this simple, economical mold test kit by following
our instructions on how to collect and mail mold samples to our lab
Environmental
Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis,
Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing
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