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BUILDING INTERIORS

ACOUSTICAL SEALANT CHOICES
AGE of a BUILDING - how to determine
AGE of PLUMBING MATERIALS & FIXTURES
AGE of AIR CONDITIONERS & HEAT PUMPS
AGE of HEATERS, BOILERS, FURNACES
AGE of WATER HEATERS
ACOUSTICAL SEALANT CHOICES
AIR BYPASS LEAKS
AIR LEAK DETECTION TOOLS
AIR LEAK MINIMIZATION
AIR POLLUTANTS, COMMON INDOOR
AIR LEAK SEALING PROCEDURE
AIR SEALING STRATEGIES
ANIMAL ALLERGENS
ANIMAL ENTRY POINTS in buildings
ANIMAL ODORS IN buildings
APPLIANCE EFFICIENCY RATINGS
ARCHITECTURE & BUILDING COMPONENT ID
ASBESTOS FLOORING HAZARD REDUCTION
ASBESTOS-FREE INSULATION MATERIALS
ASBESTOS IDENTIFICATION IN buildings
ASBESTOS LIST of PRODUCTS
ASBESTOS PHOTO GUIDE to Materials
ASBESTOS REMOVAL, Wetting Guidelines
ATTIC LEAKS, CONDENSATION & MOLD
ATTIC VENTILATION

BASEMENT CEILING VAPOR BARRIER
BASEMENT HEAT LOSS
BASEMENT LEAKS, INSPECT FOR
BASEMENT WATERPROOFING
BATH & KITCHEN DESIGN GUIDE
BATHROOM VENTILATION
BEST CONSTRUCTION PRACTICES GUIDE
Best Interior Finish Practices

BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
BLOWN-IN INSULATION

BOOKSTORE - INTERIORS
BRICK LINED WALLS
BRICK VENEER WALL INSULATION
BRICK VENEER WALL Loose, Bulged
BRICK WALL DRAINAGE WEEP HOLES
BUCKLED FOUNDATIONS due to INSULATION?
BUILDING NOISE DIAGNOSIS & CURE

CABINETS & COUNTERTOPS
CACTUS FUNGI / MOLD
CAR MOLD CONTAMINATION
CARPET DUST IDENTIFICATION
CARPET MOLD CONTAMINATION
CARPET PADDING ASBESTOS, MOLD, ODORS
CARPET STAIN DIAGNOSIS
CARPET & other STAIN TESTS
CARPET TEST PROCEDURE
CARPETING & INDOOR AIR QUALITY
CARPETING, SELECTION & INSTALLATION

CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
CEILING FINISHES INTERIOR
CEILINGS, DROP or SUSPENDED PANEL
CEILINGS, PLASTER TYPES
CEILINGS, PLASTER, LOOSE HAZARDS
CHIMNEY INSPECTION DIAGNOSIS & REPAIR
CHINESE DRYWALL HAZARDS
COMBUSTION AIR for TIGHT buildings
CONDENSATION or SWEATING PIPES, TANKS
CONDENSATION on WINDOWS & SKYLIGHTS
CORROSION in ELECTRICAL PANELS
CORROSION & MOISTURE SOURCES in PANELS
COOLING LOAD REDUCTION by ROOF VENTS
CRAWL SPACES

DECK & PORCH CONSTRUCTION
DEW POINT CALCULATION for WALLS
DEW POINT TABLE - CONDENSATION POINT GUIDE
DIRECTORY of MOLD / ENVIRONMENTAL EXPERTS
DIRT FLOOR MOLD CONTAMINATION
Disinfectants
Disinfecting Buildings with Bleach
DOORS, INTERIOR
DRYER VENTING
DRYWALL HAZARDS, CHINESE
DRYWALL INSTALLATION Best Practices
DRYWALL MOLD
DRYWALL MOLD RESISTANT

EFFLORESCENCE, Salts & White / Brown Deposits
ELDERLY & VETERANS HOME SAFETY
ENGINEERED WOOD Flooring

FIBERGLASS INSULATION
FIBERGLASS HAZARDS
FIBERGLASS INSULATION MOLD
FLAT ROOF MOISTURE & CONDENSATION
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOD DAMAGED FOUNDATIONS
FLOOD VENTS & FLOOD PORTS
FLOODS IN buildings-mold
FLOOR, CERAMIC TILE
FLOOR, CONCRETE SLAB CHOICES
FLOOR, CONCRETE SLAB POURED FINISH
FLOOR DAMAGE DIAGNOSIS
FLOOR, ENGINEERED WOOD & LAMINATES
FLOOR FRAMING & SUBFLOOR for TILE
FLOOR, KITCHEN & BATH OPTIONS
FLOOR, LAMINATE PLASTIC
FLOOR RADIANT HEAT Mistakes to Avoid
FLOOR, RESILIENT VINYL or CORK
FLOOR, STONE, GRANITE, MARBLE, AGGLOMER
FLOOR & SUBFLOOR MOLD, HIDDEN
FLOOR TYPES & DEFECTS
FLOOR TILE HISTORY & INGREDIENTS
FLOOR TILE INSTALLATION DETAILS
FLOOR WOOD AGE TYPES HISTORY
FLOOR WOOD, DAMAGE DIAGNOSIS
FLOOR, WOOD ENGINEERED, LAMINATE, INSTALL
FLOOR, WOOD FINISHES
FLOOR, WOOD INSTALLATION GUIDE
FLOOR, WOOD MOISTURE
FLOOR, WOOD RADIANT HEAT
FLOOR, WOOD SOLID STRIP, PLANK
FLOOR, WOOD TYPES
FLOORING MATERIALS, Age, Types
FORMALDEHYDE HAZARDS
FOOTING & FOUNDATION DRAINS
FOUNDATION BULGE or LEAN MEASUREMENTS
FOUNDATION CRACKS & DAMAGE GUIDE
FOUNDATION WATERPROOFING
FRENCH DRAINS
FRAMING DAMAGE, INSPECTION, REPAIR
FRAMING DETAILS for BETTER INSULATION
FRAMING DETAILS for DOUBLE WALL HOUSES
FRAMING METAL STUD PERFORMANCE
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
FUNGICIDAL SPRAY & SEALANT USE GUIDE

GAS EXPOSURE EFFECTS, TOXIC
  Carbon Dioxide - CO2
  Carbon Monoxide - CO
  METHANE GAS SOURCES
GAS DETECTION & MEASUREMENT
GAS EXPOSURE LIMITS & STANDARDS
GLARE, Sunlight/Lighting Control

HEAT LOSS in buildings
HEAT LOSS DETECTION TOOLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HEAT TAPES & CABLES on Roofs for Ice Dams
HEATING COST SAVINGS METHODS
HOT ROOF DESIGNS: Un-Vented Roof Solutions
HOUSEWRAP AIR & VAPOR BARRIERS
HOUSE DOCTOR, how-to be
HUMIDITY LEVEL TARGET

ICE DAM PREVENTION
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
INDOOR HOUSE DUST & DEBRIS
INSULATION CHOICES
Insulation Air & Heat Leaks
INSULATION FACT SHEET- DOE
INSULATION for GREENHOUSE or SOLARIUM
INSULATION IDENTIFICATION GUIDE
INSULATION INSPECTION & IMPROVEMENT
INSULATION LOCATION - WHERE TO PUT IT
INSULATION LOCATION for BRICK VENEER WALLS
INSULATION LOCATION for CAPES, CRAWLSPACES
INSULATION LOCATION for CATHEDRAL CEILINGS
INSULATION LOCATION for GREENHOUSE or SOLARIUM
INSULATION MOLD
INSULATION R-Values & Properties

KIT HOMES, Aladdin, Sears, Wards, Others
KITCHEN & BATH DESIGN GUIDE

LIGHTING, EXTERIOR GUIDE
LIGHTING, INTERIOR GUIDE
LOG HOME GUIDE

METAL LATH, PLASTER & STUCCO
MOBILE HOME INSPECTIONS
MOISTURE CONTROL in BUILDINGS

MOLD: A COMPLETE GUIDE TO MOLD
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOLD APPEARANCE - WHAT MOLD LOOKS LIKE
MOLD CLEANERS - WHAT TO USE
MOLD CLEANUP GUIDE- HOW TO GET RID OF MOLD
MOLD CONSULTANTS/INSPECTORS
MOLD CULTURE TEST KIT VALIDITY
MOLD DETECTION & INSPECTION GUIDE
MOLD or INDOOR AIR EMERGENCY RESPONSE
MOLD EXPERT, WHEN TO HIRE
MOLD FAQ's
MOLD ODORS, MUSTY SMELLS
MOLD PREVENTION GUIDE
MOLD RELATED ILLNESS GUIDE
MOLD SAFETY WARNINGS
MOLD SPRAYS, SEALANTS, PAINTS
MOLD STANDARDS
MOLD TEST KITS for DIY MOLD TESTS
MOLD TESTING METHOD VALIDITY

Nanomaterials Hazards
NOISE / SOUND DIAGNOSIS & CURE
NOISE, AIR CONDITIONER COMPRESSOR
NOISE, DUCT VIBRATION DAMPENERS
NOISE CONTROL for HEATING SYSTEMS
NOISE CONTROL for FLOORS
NOISE CONTROL for PLUMBING
NOISE CONTROL for ROOFS
NOISES COMING FROM WATER HEATER

ODORS & SMELLS DIAGNOSIS & CURE

PAINT FALURE, DIAGNOSIS, CURE, PREVENTION
PASCAL CALCULATIONS
PLASTER & BEAVERBOARD & DRYWALL
PLASTER BULGES & PILLOWS
PLASTER LATH, METAL
PLASTER, LOOSE FALL HAZARDS
PLASTER TYPE IDENTIFICATION
PLASTER VENEER Best Practices

RADIANT BARRIERS
RADIANT HEAT
RADIANT HEAT Floor Mistakes to Avoid
RADIANT HEAT TEMPERATURES
RADIANT SLAB FLOORING CHOICES
RADIANT SLAB TUBING & FLUID CHOICES
ROOF VENTILATION SPECIFICATIONS
ROT, FUNGUS, TERMITES
ROT, TIMBER FRAME

SAFETY HAZARDS & INSPECTIONS
SAFETY: Elderly & Veterans Home Safety
SAFETY for ELECTRICAL INSPECTORS
SEARS KIT HOUSES
SEPTIC SYSTEM ODORS
SEWAGE BACKUP TEST & CLEANUP
SEWAGE & SEPTIC CONTAMINANTS
SEWAGE CONTAMINATION in buildings
SEWAGE PATHOGENS in SEPTIC SLUDGE
SEWER GAS ODORS
SINKHOLES, WARNING SIGNS
SINKING BUILDINGS
SLAB CRACK EVALUATION
SMELL PATCH TEST to Track Down Odors
SOUND CONTROL in buildings

SOLAR ENERGY SYSTEMS
SOUND CONTROL in buildings
Splits in Structural Wood Beams
STAIN & BIODETERIORATION AGENT CATALOG
STAINS on buildings - QUICK GUIDE
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
STAINS on/near CHIMNEYS
STAINS & FINISHES, INTERIOR
STAINS on INDOOR SURFACES: PHOTO GUIDE
STAINS & Thermal Tracking
STAIN DIAGNOSIS on ROOFS
STAIN DIAGNOSIS on STONE
STAIRS, RAILINGS, LANDINGS, RAMPS
STONE CLEANING METHODS
STONE VENEER WALLS
STUCCO WAll FAILURES DUE TO WEATHER
STUCCO WALL METHODS & INSTALLATION
STUCCO OVER FOAM INSULATION
STUCCO PAINT FAILURES
SUMP PUMPS GUIDE
SWEATING (CONDENSATION) on PIPES, TANKS

THERMAL EXPANSION of MATERIALS
THERMAL MASS in buildings
THERMAL TRACKING Indicates Heat Loss
TRIM, INTERIOR
TRIM, INTERIOR INSTALLATION
TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof

VAPOR BARRIERS & CONDENSATION in BUILDINGS
VENTILATION in buildings
VINYL Siding or PLASTIC Window ODORS in buildings
VINYL CHLORIDE HEALTH INFO

WALL SIDING TRIM & FINISHES
WALL FINISHES INTERIOR
WATER BARRIERS, EXTERIOR BUILDING
WATER ENTRY in buildings
WIND WASHING INSULATION At EAVES
WINDOWS & DOORS
WINTERIZE A BUILDING
WOOD Burning Heaters Fireplaces Stoves
WOOD FLOOR DAMAGE

More Information

Nail pop mechanism in walls (C) Carson Dunlop Associates Interior Ceilings: How to Inspect, Diagnose, & Repair Problems in Building Interior Ceilings
InspectAPedia®  -      

  • Definition and illustration of types of interior ceiling finishes and systems: types of plaster ceilings, drywall, acoustic tile, suspended ceiling tiles, stucco, textured paint, stippled ceilings
  • Catalog of common interior ceiling defects, how they are recognized, what causes them
  • Water damaged or stained interior ceilings
  • Cracks in interior ceilings
  • Plaster cracks, loose plaster, falling plaster ceilings
  • Mold on interior ceilings
  • Nail pops: cause, cure, and prevention in ceilings
  • Roof truss uplift: cause of cracks, nail pops: cause, cure, and prevention of wall/ceiling cracks
  • Questions & answers about troubleshooting & fixing cracks, sags, loose plaster, & other interior ceiling problems

This article describes the major ceiling finishes used in buildings and identifies common problems in, and repair of building interior ceilings and ceiling materials.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.

Information is provided about visual clues of building condition, such as evidence of a history of leaks, as well as evidence of hazardous materials and conditions such as the probable presence of animal allergens, asbestos, or mold. We discuss how to identify and correct various building leaks, moisture, and venting problems such as ice dams, blocked attic ventilation, excessive indoor humidity, how to prevent indoor mold, and how to respond to building floods and similar emergencies. Also see Best Interior Finish Practices and see Q&A on Building Interiors: Leaks, Stains, Damage, Repairs and see FLOOR DAMAGE DIAGNOSIS and CEILINGS, PLASTER TYPES. The photo at page top shows the grid system for supporting a suspended panel ceiling.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Interiors Ceiling Finishes: Types, Defect Recognition, Repair for Building Interiors

The following building interior ceiling finish type descriptions, and interior wall defect descriptions are adapted and expanded from original citations provided courtesy of Carson Dunlop Associates, Home Reference Book, with permission.

Inspecting an interior wall (C) Carson Dunlop Associates

The sketch at left illustrates two simple methods for inspecting interior building ceilings for common defects: use of parallel or oblique lighting (see for details) and tapping. The drawing is provided courtesy of Carson Dunlop Associates and appears in their Illustrated Home.

At USING LIGHT TO FIND MOLD we provide a detailed example and procedures for using lighting to find otherwise hard-to-see building defects.

Types of Major Ceiling Finishes Described

Ceiling finishes provide a decorative skin to conceal building components.

Ceiling finishes hide structural members, insulation, ductwork, pipes, and wires. Most good ceiling finishes are flat and straight. Surfaces may be smooth or textured and better ceiling finishes are durable.

Some ceiling finishes are versatile, taking decorative finishes such as stain, paint or wallpaper readily.

Ceilings may make a decorating statement, or may be simply background. In some cases, the combustibility of ceiling finishes may be of interest. Below roofs, kitchens and bathrooms, resistance to water damage is an asset.

Plaster / Drywall Wall Materials, Types, Properties

Please see our discussion at and CEILINGS, PLASTER TYPES where we provide details about types of plaster ceilings, and also see our plaster and drywall information at WALL FINISHES INTERIOR.

Also see CHINESE DRYWALL HAZARDS.

As we discussed about interior walls, our AGE of a BUILDING - how to determine article series we explain how you can guesstimate the age of a building by taking a look at its wall construction and finish materials.

Acoustic Ceiling Tiles

Asbestos containing acoustic ceiling tiles

Acoustic ceiling tiles, typically made of fiber board and perforated to improve their acoustic performance, have been popular since the 1950s.

Typically, they are 12 inches by 12 inches and are stapled or nailed to strapping. This type of ceiling tile was often installed when finishing a basement, or was installed over a damaged plaster ceiling.

The tiles have better acoustic properties than plaster and drywall, although they are subject to mechanical damage and water damage, similar to drywall or plaster. Repairs are easy if matching tiles can be found. The tiles can be painted, with some loss of acoustic performance.

Often you will find that acoustic ceiling tiles have been installed on furring strips nailed over an older ceiling that was in poor condition, such as we show in this additional photo where demolition was in process.

See details about asbestos in ceiling products found at ASBESTOS CEILING TILES, Asbestos-Containing.

Suspended Ceilings and Suspended Ceiling Tiles - Properties, Photos

Suspended ceiling with leak stains (C) Daniel Friedman

Suspended ceilings or suspended ceiling tiles became popular in North America in the 1960s, and can be made of fiber board or fiberglass, for example. Some have a plastic coating.

Details about suspended ceilings or drop panel ceilings are found at

CEILINGS, DROP or SUSPENDED PANEL

Metal Ceilings - Properties, Photos

Metal ceiling (C) Daniel Friedman

Metal ceilings were typically tin and most often were installed in kitchens, during the late 1800s and early 1900s. Their design was often a decorative square pattern intended to simulate ornate plaster ceilings. This was a fairly durable ceiling system and in some areas has become fashionable again. The metal is normally painted.

The metal ceiling in our photo (left) is an antique metal ceiling installed in a New York City restaurant. You can see in the left of the photo that a wooden beam was also wrapped in decorative embossed metal.

This link to a different metal ceiling photo shows a typical example of metal ceiling components that are rusting through from leaks above.

Don't be fooled. There are also some metal ceiling lookalike products that are actually drop-in panels, typically 2' x 2' or 2' or larger, that are actually a suspended ceiling system. It's easy to spot a metal panel suspended ceiling by looking more closely for its supporting grid.

Stucco/Textured Interior Wall Finishes

Interior stucco is essentially plaster, and is typically installed in a two or three coat process. The finish is often sculpted or worked to provide a decorative appearance. The texturing is done with trowels, sponges, brushes, or other tools to give the desired effect.

See these stucco articles for details: STUCCO WALL METHODS & INSTALLATION, and STUCCO OVER FOAM INSULATION (on exteriors), and STUCCO PAINT FAILURES (on building exterior or interior walls).

Common Interior Ceiling Finish Problems

Water Damaged or Stained Interior Ceilings

As we also discuss at WALL FINISHES INTERIOR, water damage is one of the most common problems on interior finishes. Common water sources that show up as ceiling leaks or leak stains include roof leaks, flashing leaks, ice damming, window and skylight leaks, plumbing leaks, leaks from hot water heating systems, and condensation.

Water damage in or on a ceiling may also result from such things room humidifiers or dehumidifiers, and other sources of indoor water or high moisture levels, but the most common source of water damage to ceilings is of course leaks from above.

Closet ceiling leak stain (C) D Friedman, L.D. The photo [at left] of water stains on a closet ceiling is discussed along with diagnostic suggestions at Q&A on Building Interiors: Leaks, Stains, Damage, Repairs

When looking into ceiling leak stains, you want to find

  1. the source of the water,
  2. whether the problem is still active,
  3. whether there is any concealed damage
  4. the cost to correct the water problem if needed, e) and the cost to repair the damaged building materials.

While water damage often looks more serious than it is, a stain such as the one in our photo (above left) might in fact be hiding a larger mold problem or rot or insect damage that were caused by a long-term leak into the structure.

On the other hand, short term exposure to water will not harm many building materials. [For an exception see CARPET MOLD CONTAMINATION]

Ceiling (or wall) plaster and drywall however, are easily damaged by water. Stains appear quickly and persist after the problem is solved. The material that can be easily seen is the first material to deteriorate. Mold can develop on the front or back surface of plaster or drywall if it is chronically wet. Mold will not disappear but will go dormant if the moisture source is removed.

Both plaster and drywall ceilings that have been damaged can be readily patched where small damaged areas are noted. But as we discuss at Q&A on Building Interiors: Leaks, Stains, Damage, Repairs, if there is evidence that a long term leak has been going on, further investigation - a look into the ceiling or wall cavity - may be justified, and if a large mold contamination is found (much more likely on drywall than on plaster) a cleanup is needed.

Drywalling over old plaster or drywall is sometimes done where large areas are damaged.

Watch out: do not just drywall over building ceilings or walls where there has been a long history of leakage or where there is a serious mold problem. Doing so risks covering up a more serious problem that can lead to the need to remove the drywall, clean and fix conditions in the ceiling or wall, and then put it back - doubling the cost of the job.

If you are considering drywalling over an old ceiling or wall where there is evidence of leakage or mold, make a few test cuts into the worst or most-suspect areas to look into the building cavities for damage before proceeding.

See complete details about building water entry beginning at WATER ENTRY in buildings.

For a complete guide to diagnosing stains on building interiors see STAIN DIAGNOSIS on BUILDING INTERIORS.

Chinese Drywall Outgassing Hazards at Building Ceilings (or Walls)

A/C coil corrosion - Chinese Drywall - US CPSC

Details are found at at CHINESE DRYWALL HAZARDS, This article describes a corrosive and smelly sulphur outgassing problem that occurs in certain homes built or renovated since 2001. Excerpts are below.

The image of corrosion on a cooling coil that was blamed on Chinese drywall outgassing is provided by the U.S. CPSC.

 

Cracks or Sags in Plaster or Drywall Interior Ceilings, Diagnosis & Repair

Plaster lath board (C) Daniel Friedman

Large sections of ceilings may become loose where plaster has lost many of its keys due to vibration and wear and tear. Where there is danger of plaster falling, this should be corrected promptly. People can be seriously hurt by plaster falling, especially from a ceiling.

A sagging ceiling might indicate that the plaster or drywall is about to fall.

Most interior ceiling or wall cracks are cosmetic. In those cases, patching and monitoring the crack for recurrent or ongoing movement makes sense. Where cracks are accompanied by sagging, at least partial ceiling replacement may be necessary.

Details are at PLASTER, LOOSE FALL HAZARDS where we illustrate loose plaster and report a case of a catastrophic plaster ceiling collapse.

Sagging plaster ceilings (in our photo above and in Carson Dunlop Associates' sketches below, are traced to broken plaster keys - the protruding plaster that projected through the original plaster wood or metal lath and formed a "key" that held the plaster in place.

Mold on Interior Ceiling Surfaces

Where there is a large (more than 30 sq.ft.) reservoir of contiguous indoor mold, such as is shown on our moldy ceiling photo below, there are almost certainly health hazards for building occupants. But as we discuss at Q&A on Building Interiors: Leaks, Stains, Damage, Repairs, small moldy areas may be of no significant health concern and can be cleaned or removed by most homeowners or a handyman who follow simple basic precautions.

white mold on pine paneling is hard to see unless illuminaged correctly

We emphasize in all of our notes on indoor mold inspection and testing that a competent inspection for mold contamination begins outside, and should include the entire structure.

An inspection should consider not just current leaks, but stains or construction details making leaks likely, the history of building leaks or moisture problems, or building conditions or features that make water or moisture problems likely in certain areas. These observations aid in deciding whether or not the risk of a hidden mold problem justifies more in-depth invasive inspection and testing.

But in our photograph (above-left), no inspection is necessary to know that a professional mold cleanup is needed at this building. Nevertheless, an independent (no conflicts of interest) expert who has no connection with the mold cleaning company, can define the necessary scope of work and can assist later in confirming that the cause as well as the effect of conditions that led to this moldy ceiling have been adequately addressed.

At USING LIGHT TO FIND MOLD we provide a detailed example and procedures for using lighting to find mold on surfaces where mold may be present but where it is not immediately obvious.

Roof Truss Uplift and Cracks or Ceiling Nail Pops: Details of Truss Uplift Cause and Cure of Interior Wall/Ceiling Gaps or Cracks

Here we provide a definition of roof truss uplift, we explain why truss uplift occurs, where truss uplift cracks will appear, and how roof truss uplift cracking can be avoided or corrected.

According to Carson Dunlop Associates,

This cosmetic problem in homes in cold climates with roof trusses may result in significant cracks between interior walls and ceilings, or between interior walls and floors. The cause is upward bowing of the roof trusses to which the ceilings are attached.

The ceiling/wall juncture cracks typically open in the winter and close in the summer. These ceiling cracks can be very alarming, but are not a structural issue.

As we also discuss at WALL FINISHES INTERIOR, roof truss uplift is a well-understood cause of cracks at the wall/ceiling juncture at building walls located under the center (usually) of certain roof trusses.

Truss uplift explanation (C) Carson Dunlop Associates

Roof truss uplift occurs when the bottom chord of the truss is exposed to significantly different moisture or temperature conditions than the rest of the roof truss.

For example if the bottom of the truss is buried in insulation while the remainder is in the open attic air, this condition can occur.

Builders avoid truss uplift cracking or ceiling nail pops by using special truss uplift clips to connect the ceiling and wall drywall while avoiding nailing or screwing the ceiling to the bottom of the trusses within 24" of the building walls.

[See the roof truss uplift remedial action sketch just below.]

Why does truss uplift appear at interior partitions in the center of a building?

The differences in temperature and perhaps humidity that we just described can cause the roof truss to arch upwards at its center, often seasonally as attic temperatures and moisture conditions vary. Because the truss ends are secured to building exterior walls - a location that resists outward thrust, as the truss bottom chord wants to expand along its length, the force pushes it upwards into the attic space.

Truss uplift explanation (C) Carson Dunlop Associates

Therefore roof truss uplift is most likely to be observed at the ceiling-wall juncture of central interior wall partitions that run at right angles to the direction of the roof trusses, or in other words, interior partitions that are parallel to the house front and rear eaves.

Tthat's where truss uplift cracks may occur (typically in the center of the truss).

The drawings of roof truss uplift and corrective measures for truss uplift shown here are provided courtesy of Carson Dunlop Associates and appears in their Illustrated Home.

Questions & Answers regarding this article

Questions & answers about troubleshooting & fixing cracks, sags, loose plaster, & other interior ceiling problems.

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Technical Reviewers & References

  • InspectAPedia.com® - Daniel Friedman - Publisher & Editor.
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  • Additional technical contributors & reference sources for this article are listed below.

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.

CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
CEILING FINISHES INTERIOR
CEILINGS, DROP or SUSPENDED PANEL
CEILINGS, PLASTER TYPES
CEILINGS, PLASTER, LOOSE HAZARDS
CHINESE DRYWALL HAZARDS

  • Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
  • Plastering Skills, F. Van Den Branden, Thomas L. Hartsell, Amer Technical Pub (July 1, 1985), ISBN-10: 0826906575, ISBN-13: 978-0826906571 [purchase at Amazon.com]

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

  • Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
  • Home Reference Book - Carson Dunlop The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 2010, $69.00 U.S., is available from Carson Dunlop. The Home Reference Book is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. InspectAPedia.com ® author/editor Daniel Friedman is a contributing author. Field inspection worksheets are included at the back of the volume.
  • America's Favorite Homes, mail-order catalogues as a guide to popular early 20th-century houses, Robert Schweitzer, Michael W.R. Davis, 1990, Wayne State University Press ISBN 0814320066 (may be available from Wayne State University Press)
  • American Plywood Association, APA, "Portland Manufacturing Company, No. 1, a series of monographs on the history of plywood manufacturing",Plywood Pioneers Association, 31 March, 1967, www.apawood.org
  • Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
  • Asbestos: How to find and recognize asbestos in buildings - visual inspection methods, list of common asbestos-containing materials
  • ASHRAE resource on dew point and wall condensation - see the ASHRAE Fundamentals Handbook, available in many libraries. The following three ASHRAE Handbooks are also available at the InspectAPedia bookstore in the third page of our Insulate-Ventilate section:
    • 2005 ASHRAE Handbook : Fundamentals : Inch-Pound Edition (2005 ASHRAE HANDBOOK : Fundamentals : I-P Edition) (Hardcover), Thomas H. Kuehn (Contributor), R. J. Couvillion (Contributor), John W. Coleman (Contributor), Narasipur Suryanarayana (Contributor), Zahid Ayub (Contributor), Robert Parsons (Author), ISBN-10: 1931862702 or ISBN-13: 978-1931862707
    • 2004 ASHRAE Handbook : Heating, Ventilating, and Air-Conditioning: Systems and Equipment : Inch-Pound Edition (2004 ASHRAE Handbook : HVAC Systems and Equipment : I-P Edition) (Hardcover)
      by American Society of Heating, ISBN-10: 1931862478 or ISBN-13: 978-1931862479
      "2004 ASHRAE Handbook - HVAC Systems and Equipment The 2004 ASHRAE HandbookHVAC Systems and Equipment discusses various common systems and the equipment (components or assemblies) that comprise them, and describes features and differences. This information helps system designers and operators in selecting and using equipment. Major sections include Air-Conditioning and Heating Systems (chapters on system analysis and selection, air distribution, in-room terminal systems, centralized and decentralized systems, heat pumps, panel heating and cooling, cogeneration and engine-driven systems, heat recovery, steam and hydronic systems, district systems, small forced-air systems, infrared radiant heating, and water heating); Air-Handling Equipment (chapters on duct construction, air distribution, fans, coils, evaporative air-coolers, humidifiers, mechanical and desiccant dehumidification, air cleaners, industrial gas cleaning and air pollution control); Heating Equipment (chapters on automatic fuel-burning equipment, boilers, furnaces, in-space heaters, chimneys and flue vent systems, unit heaters, makeup air units, radiators, and solar equipment); General Components (chapters on compressors, condensers, cooling towers, liquid coolers, liquid-chilling systems, centrifugal pumps, motors and drives, pipes and fittings, valves, heat exchangers, and energy recovery equipment); and Unitary Equipment (chapters on air conditioners and heat pumps, room air conditioners and packaged terminal equipment, and a new chapter on mechanical dehumidifiers and heat pipes)."
    • 1996 Ashrae Handbook Heating, Ventilating, and Air-Conditioning Systems and Equipment: Inch-Pound Edition (Hardcover), ISBN-10: 1883413346 or ISBN-13: 978-1883413347 ,
      "The 1996 HVAC Systems and Equipment Handbook is the result of ASHRAE's continuing effort to update, expand and reorganize the Handbook Series. Over a third of the book has been revised and augmented with new chapters on hydronic heating and cooling systems design; fans; unit ventilator; unit heaters; and makeup air units. Extensive changes have been added to chapters on panel heating and cooling; cogeneration systems and engine and turbine drives; applied heat pump and heat recovery systems; humidifiers; desiccant dehumidification and pressure drying equipment, air-heating coils; chimney, gas vent, fireplace systems; cooling towers; centrifugal pumps; and air-to-air energy recovery. Separate I-P and SI editions."
    • Principles of Heating, Ventilating, And Air Conditioning: A textbook with Design Data Based on 2005 AShrae Handbook - Fundamentals (Hardcover), Harry J., Jr. Sauer (Author), Ronald H. Howell, ISBN-10: 1931862923 or ISBN-13: 978-1931862929
    • 1993 ASHRAE Handbook Fundamentals (Hardcover), ISBN-10: 0910110964 or ISBN-13: 978-091011096
  • Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
  • Brick nogging used as soundproofing is mentioned in this article on Popular Forest
  • Brick Nogging, Historical Investigation and Contemporary Repair, Construction Specifier, April 2006. Historical use of brick in timber-framed buildings, drawing on the investigations of the Kent Tavern in Calais, VT. "Brick nogging is a European method of construction which was brought to the new world in the early-nineteenth century. It was a common construction method that employed masonry as infill between the vertical uprights of wood framing." -- quoting the web article review.
  • Photo of very rough in-wall brick nogging at an architects website
  • Building Research Council, BRC, nee Small Homes Council, SHC, School of Architecture, University of Illinois at Urbana-Champaign, brc.arch.uiuc.edu. "The Small Homes Council (our original name) was organized in 1944 during the war at the request of the President of the University of Illinois to consider the role of the university in meeting the demand for housing in the United States. Soldiers would be coming home after the war and would be needing good low-cost housing. ...  In 1993, the Council became part of the School of Architecture, and since then has been known as the School of Architecture-Building Research Council. ... The Council's researchers answered many critical questions that would affect the quality of the nation's housing stock.
    • How could homes be designed and built more efficiently?
    • What kinds of construction and production techniques worked well and which did not?
    • How did people use different kinds of spaces in their homes?
    • What roles did community planning, zoning, and interior design play in how neighborhoods work
  • "An Example of Colonial Paneling", Norman Morrison Isham, The Metropolitan Museum of Art Bulletin, Vol. 6, No. 5 (May, 1911), pp. 112-116, available by JSTOR.
  • Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
  • Gypsum Construction Guide, National Gypsum Corporation
  • Gypsum Construction Handbook [purchase at Amazon.com] H17, Technical Folder SA920 and PM2, PM3 and PM4, United States Gypsum Company, 125 South Franklin ST., PO Box 806278, Chicago, IL 60680-4124,
  • Humidity: What indoor humidity should we maintain in order to avoid a mold problem?
  • 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
  • Insulation Types, table of common building insulation properties from U.S. DOE. Readers should see INSULATION R-Values & Properties our own table of insulation properties that includes links to articles describing each insulation material in more detail.
  • Lath & Plaster Systems, 092300/NGC, National Gypsum Lath and Plaster Systems, National Gypsum Corporation, 800-628-4662 describing National Gypsum's Kal-Kore brand plaster base
  • Metal Lath Specifications, Specification for metal lath and accessories, Lath and Plaster from Amico, a lath and plaster accessory producer.
  • Mobile Home Inspections common defects unique to factory built housing, inspection methods
  • The National Institute of Standards and Technology, NIST (nee National Bureau of Standards NBS) is a US government agency - see www.nist.gov
    • "A Parametric Study of Wall Moisture Contents Using a Revised Variable Indoor Relative Humidity Version of the "Moist" Transient Heat and Moisture Transfer Model [copy on file as/interiors/MOIST_Model_NIST_b95074.pdf ] - ", George Tsongas, Doug Burch, Carolyn Roos, Malcom Cunningham; this paper describes software and the prediction of wall moisture contents. - PDF Document from NIS
  • Nogging: See this photo of exposed bricks on a building exterior on a building exterior in Canada. [Thanks to Carson Dunlop, Toronto - see References below].
  • Pergo AB, division of Perstorp AB, is a Swedish manufacturer or modern laminate flooring products. Information about the U.S. company can be found at http://www.pergo.com where we obtained historical data used in our discussion of the age of flooring materials in buildings.
  • Piquet Wall Construction: See this photo of piquet wall construction - involving timber-framed wall construction with long top girts, diagonal timber bracing, and small diameter logs placed vertically along with concrete chinking to fill in the wall plane.
  • Plank House Construction: weblog from plankhouse.wordpress.com/2009/01/25/plank-house-construction/ and where plank houses were built by native Americans, see
    Large 1:6 Scale Plank House Construction / P8094228, Photographer: Mike Meuser
    06/12/2007 documented at yurokplankhouse.com where scale model Museum quality Yurok Plank Houses are being sold to raise money for the Blue Creek - Ah Pah Traditional Yurok Village project.
  • Plastering, PM 5, Product & Systems Technology, US Gypsum, May 1998, web search 10.5.2010, original source: http://www.usg.com/rc/technical-articles/plaster/
    plastering-technical-guide-veneer-plaster-joint-reinforcement-systems-en-PM5.pdf
    United States Gypsum Company, 125 South Franklin ST., PO Box 806278, Chicago, IL 60680-4124,
    Paraphrasing from this document: USG uses the term shadowing in this document in describing the visual effect over gypsum board joints caused by the lower moisture absorption rate (take-up) and lower capacity than gypsum base face paper. Shadowing at joints occurs where veneer plaster is applied over tape joints, requiring a second coat to completely hide the tape, providing a visually uniform surface. USG Advises: "This [second] cover coat must be allowed to harden and dry before plaster application is started.
  • Plastering Skills, F. Van Den Branden, Thomas L. Hartsell, Amer Technical Pub (July 1, 1985), ISBN-10: 0826906575, ISBN-13: 978-0826906571 [purchase at Amazon.com]
  • Rubblestone Wall Filler: See this Lartigue House using exterior-exposed rubblestone filler between vertical timbers of a post and beam-framed Canadian building.
  • How to Clean Moldy Wood Framing & Sheathing How to clean/seal mold from/on exposed lumber or plywood subfloor or roof sheathing indoors - some suggestions based on our field and laboratory research
  • Lighting, proper use of: proper aiming of a good flashlight can disclose hard to see but toxic light or white mold colonies on walls.
  • Manufactured & Modular Homes: Modular Building Systems Association, MBSA, modularhousing.com, is a trade association promoting and providing links to contact modular builders in North America. Also see the Manufactured Home Owners Association, MHOAA, at www.mhoaa.us. The Manufactured Home Owners Association of America is a National Organization dedicated to the protection of the rights of all people living in Manufactured Housing in the United States.
  • How to Find and Test For Mold in buildings A "how to" photo and text primer on finding and choosing the right spots to test for mold in buildings
  • Mold-Resistant Building Practices, advice from an expert on how to prevent mold after a building flood and how to prevent mold growth in buildings by selection of building materials and by anti-mold construction details.
  • "Weather-Resistive Barriers [copy on file as /interiors/Weather_Resistant_Barriers_DOE.pdf ] - ", how to select and install housewrap and other types of weather resistive barriers, U.S. DOE
  • Weaver: Beaver Board and Upson Board: Beaver Board and Upson Board: History and Conservation of Early Wallboard, Shelby Weaver, APT Bulletin, Vol. 28, No. 2/3 (1997), pp. 71-78, Association for Preservation Technology International (APT), available online at JSTOR.
  • What Style Is It?: A Guide to American Architecture, Rev., John C. Poppeliers, S. Allen Chambers, Wiley; Rev Sub edition (October 6, 2003), ISBN-10: 0471250368, ISBN-13: 978-0471250364
  • ...

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