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Severe mold contamination in a home (C) Daniel Friedman

Table of Kinds of Mold Growth Found on Building Surfaces
InspectAPedia®  -    

  • Photos and detailed list of mold genera/species most often found on specific building surfaces, materials, or contents
  • Which molds are most commonly found indoors?
  • What are the Most Common Indoor Molds Found on Building Surfaces?
  • Most common molds on drywall, paper, wood, plastic, metal, furniture, bedding, clothing, shoes, etc. in or on buildings
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 InspectAPedia.com/appointment.htm.

Here are a table and photographs of molds most commonly found on specific building surfaces or in/on building materials, furnishings, and other building contents. Our page top photo of a mold damaged home shows an area with many different surfaces, materials, and in some cases different genera/species of mold contamination.

Like bird-watching, knowing what molds are likely to be present, what they look like, and what they like to eat, in other words, knowing some mycology, can make a significant difference in what a building inspection for mold actually turns up. See MOLD FREQUENCY in BUILDINGS for a table of what mold genera/species are frequently found in indoor mold tests.

The difference between what molds are found in buildings and what molds commonly grow on various building surfaces is that most mold tests and mold reports involve samples collected by people who are not expert at recognizing and sampling mold in buildings. So easy-to-see molds are over-reported and hard-to-see molds are under-reported in consumer-generated mold tests and samples. This reporting error also confounds attempts to correlate mold related illness and sick building complaints with specific genera or species of indoor mold.

Simple "mold screening methods" which omit the inspection, and "test only" sampling methods, such as air and culture methods can produce very unreliable results when used quantitatively - as we discuss at IAQ Methods and at other articles at this website.

© Copyright 2010 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.

Table of Common Indoor Molds Found on Building Surfaces

We list here the most common mold genera/species that our field investigations have detected in the screening of more than 2000 buildings between 1986 and the present. We are conducting ongoing research on the presence of specific molds on building surfaces and materials. Comments, critique, and contributions are invited. Contact Us.

NOTICE: the molds we list as most-commonly found on building surfaces and materials in the table below are by no means the only genera/species that may appear in a specific build ling or case. Further, the mold genera/species that grows on a particular surface depends primarily on its growth conditions, in particular moisture level, and of course temperature, light exposure, and similar factors.

It is often the case that multiple mold genera/species are present on the same surface; some molds may be growing parasitically on others, and the particular mold found at a particular spot on a building surface may depend on the moisture level at that location.

Our investigations include extreme-mold cases in which a building had been subjected to severe water damage and left unattended for weeks or months, leading to extensive mold growth throughout the structure on many or nearly all surfaces. In those extremely-moldy buildings we collected tape samples of mold on each different type of surface or material in the building as well as collecting vacuum and air samples of mold to observe the dominant airborne molds in those environments.

Our OPINION is that the genera of Aspergillus ranks as a wide-lead first as most widely adapted to grow on the greatest number of different indoor building surfaces, with Penicillium sp. probably second. As we discuss at MOLD FREQUENCY in BUILDINGS, these two mold genera are probably under-reported by consumers who collect mold samples using test kits as well as many mold test consultants who naturally focus on the most visually obvious dark or "black" molds in buildings. Outdoors we most often find the king of molds, Cladosporium sp. on widespread building surfaces.

Table of Common Indoor Building Molds on Surfaces or In Materials
Building Surface or Material
Links Photographs of Mold on Various Materials found On or In Buildings
Mold Comments
Air duct mold,
metal un-lined ducts
fiberglass-lined air ducts
plastic flex-duct materials
metal flex duct materials
Cladosporium sp. / C. sphaerospermum Common in various duct systems especially where normal organic building dust and debris accumulate along with water downstream of condensate blow-off in the air handler or where condensation has occurred, or where external air duct leaks occurred into rooftop mounted ducts or where building ducts were exposed to flooding.
Aluminum siding & aluminum exterior trim mold - building exteriors Various Associated with damp, shaded locations; don't mistake algae or dirt for mold;
Appliances, painted or porcelain surfaces of refrigerators, etc. includes trivial non-risk mold quanties on refrigerators, and gross dangerous mold in mold-contaminated homes such as on this moldy range draft hood. Refrigerator gaskets: Cladosporium sp. / C. sphaerospermum

Presence of mold probably depends mostly on the presence of organic dust and debris such as food, grease, house dust or animal dander.

Very different molds grow on painted or porcelain appliance surfaces than those most often found on rubber or plastic parts.

Art works (joint project photo courtesy Ulrik Runeberg, Museo de Arte Contemporaneo de Puerto Rico), oil on canvas (others available) Cladosporium sp.; also Penicillium sp. & Aspergillus sp. especially on masonite substrates Varies widely by paint chemistry, substrate of fabric, hardboard, wood, and varies significantly between exposed surface and hidden surfaces. (Study projects with several art museum conservators include mold contamination, bleed-through from hardboard substrates, and paint failures on historic buildings and artifacts.
Asbestos pipe insulation, painted cloth covering Cladosporium sp. / C. sphaerospermum  
Asbestos floor tiles or vinyl asbestos tiles Rare unless coated with paint or organic debris;  
Attic surfaces - wood rafter framing, plywood roof sheathing, pine board roof sheathing, attic floors, attic insulation, attic stairs, contents stored in attics Cladosporium sp.; C. sphaerospermum;
Aureobasidium pullulans;
Ulocladium sp.;
Pithomyces sp.;
See Roof Sheathing, Framing-wood, Insulation; also see VENTILATION in BUILDINGS
Barns, common mold on barn framing (excluding moldy hay, straw, leather)    
Bathroom mold: bath tiles, bathroom tub caulk, porcelain fixtures, bath ceilings, wallpapered bathroom walls, hidden mold such as behind or under bathroom vanity cabinets   See Ceramic Tile mold
Beams, wooden girders in buildings, especially in wet or damp basements or crawl spaces Cladosporium sp.; C. sphaerospermum;
Aspergillus sp.;
Penicillium sp.;

For wet basements and crawl spaces, also see WATER ENTRY in BUILDINGS

For log homes with moisture and mold problems see LOG HOME Leak Diagnosis & Cure

And for buildings subject to flooding, see FLOOD Damage Assessment & Repairs

Bedding, pillow surfaces, sheets, fabrics  May vary by fabric fiber type, cotton vs. synthetic
Books, mold on books

Aspergillus sp. on cloth bindings

Cladosporium sp.; on exposed edges of paper, varying by organic dust level;

Varies significantly by binding type and glue, cloth, paper, etc.
Cabinets, kitchens or bath vanities, visible and hidden moldAspergillus sp.;
Penicillium sp.;
Varies by cabinet material, wood, pressboard, paint, and presence of kitchen grease or food particles; Also very significant variation between coated or finished surfaces and un-coated or un-finished surfaces such as cabinet backs.
See Green Mold for photos of green mold on indoor cabinets & furniture.
Cardboard boxes, mold on

Stachybotrys chartarum;

Aspergillus sp.;
Penicillium sp.;

Also harder cardboard or other paper boxes such as shoe boxes, cigar boxes. See See Green Mold for photos of very moldy cardboard box.
Carpeting, visible carpet mold and hidden mold in carpets and carpet padding. Note that mold contamination on carpeting is primarily where carpet has been wet, but may also vary by traffic location and debris tracked-in. Various molds and yeasts. Varies by carpet material, fiber type, and exposure to food, animal dander, other. See CARPET MOLD CONTAMINATION.
Cedar closet materials: wall boards, composite cedar sheathing Aspergillus sp.;
Penicillium sp.;

 
Ceramic tile, tile grout, tile caulk in baths and other areas Cladosporium sp.; C. sphaerospermum; more common where tile, grout, or caulk is left wet and has become coated with soap or other organic material - normally small in area & impact unless hidden leaks occurred behind tile or marble surfaces
Ceiling tiles, visible and hidden mold Aspergillus sp./A. versicolor;
Penicillium sp.;

Yeasts.
Varies by material used, plastic vs. paper surfaces, painted or not
Chipboard or pressboard used for cabinets, counters, furniture, or for shelving Aspergillus sp./A. versicolor;
Penicillium sp.;

Yeasts.
Trichoderma sp./T. viride..
 
Closet mold, visible and hidden mold commonly found in closets & pantries    
Clothing, visible and hidden moldAspergillus sp.;
Penicillium sp.;
Varies by fabric, natural vs. synthetic fiber, leather vs. cloth, exposure to food or other contaminants
Copper piping, mold growth on piping surfaces uncommon Mold growth may appear on painted copper surfaces or on organic dust and debris settled on copper surfaces;
Counter tops, kitchen or bath, plastic laminates. Aspergillus sp.;
Penicillium sp.;
on un-finished surfaces.
Plastic laminates. Mold growth on stone counter tops is rare and usually depends on the presence of biological contaminants such as food.
Dirt, crawl space surfaces, visible and hidden mold Various basidiomycetes; soil fungi; See Mold on Dirt Floors and see Crawlspace Mold Advice
Doors, hollow core luan or vinyl-coated, painted and un-painted surfaces, visible and hidden mold   We find that different mold genera/species grow on different hollow core surfaces where wood species vary, for example different molds will be found on the luan door face than on the pine door edges.
Doors, solid wood, pine, painted or clear-coated and unpainted, visible and hidden mold    
Drywall, gypsum board, visible and hidden mold - very common mold reservoir in buildings where drywall has been wet, exposed to flooding, or exposed to high humidity - don't forget to check wall cavities
Drywall gypsum board (such as Sheetrock™), not treated for mold resistance, visible and hidden mold

Stachybotrys chartarum - most wet area.

Cladosporium sphaerospermum,

Aspergillus sp., A. flavus.

Penicillium sp.;

Synonym: gypsum board. Significantly, mold growth may be rare or absent on un-painted joint compound at tape joints. Mold growth on drywall generally varies by genera/species at different heights from a wet floor as moisture level in the material varies. Mold growth on drywall may be interrupted at horizontal drywall joints. Mold growth on the exposed "room side" of drywall may be a different genera/species and also very different in quantity from mold growth found on wall-cavity side.

See See Hidden Mold in Wall Cavities

See SAMPLING DRYWALL for an example of three different molds on drywall at different moisture levels and heights from a wet floor.
See Black Mold  for photos of several different black molds on drywall.
See Red Mold for very moldy wall cavity side of drywall that showed no mold on the exposed or room side.
Also see SHEATHING, Gypsum board.

Many mold species, varying by moisture level in the drywall at different locations or distances from the moisture source (such as a wet floor in a basement or a laundry room)

Ducts, fiberglass-lined HVAC, visible and hidden mold

Cladosporium sp.; C. sphaerospermum;

Rare:
Aspergillus sp.;
Penicillium sp.;
Stachybotrys sp. on paper facing;

See Why does mold grow in fiberglass? for discussion of mold in HVAC ducts
Ducts, plastic lined HVAC, visible and hidden mold Rare. Depends on the presence of house dust (containing organic debris) and presence of moisture.
Doors, interior, hollow core, visible and hidden mold Aspergillus sp.;
Penicillium sp.;

Varies by wood species and coating. Hollow core luan doors show different mold genera/species on the luan surface from that found on the surface of solid pine used in door edges. Variations also among coatings: paint, stain, varnish, polyurethane.

See White Mold for photos of moldy solid and hollow core doors.

Doors, interior, solid pine, visible and hidden mold Aspergillus sp.;
Penicillium sp.;
Varies by coating.
Fiberglass, visible and hidden mold   see Insulation
Floor sheathing, OSB oriented strand board, visible and hidden mold

Cladosporium sp.; C. sphaerospermum;

Stemonitis sp.

See Brown Mold for photos of mold on OSB including stunning photos of Stemonitis sp. on a bathroom floor.
Floor sheathing or subflooring, plywood, visible and hidden mold

Aureobasidium pullulans common in attics on roof sheathing;

Cladosporium sp., C. sphaerospermum, common on roof sheathing;

Less common:
Taeoniella sp., T. rudus, on plywood subfloor exposed to leaks such as at sliding entry doors.

See Black Mold  for photos of Taeoniella sp., T. rudus, and other dark molds on plywood.

See Green Mold for photos of green mold on plywood subfloor over a wet crawl space.

Floor sheathing, pine tongue & groove, visible and hidden mold

Aspergillus sp.;
Penicillium sp.;

Trichoderma sp., T. viride (green), and T. harzianum

 
Flooring, vinyl tiles or sheet vinyl, visible and hidden mold    
Flooring, wood strip, visible and hidden mold    
Framing lumber, wall studs, ceiling joists, roof rafters, un-treated lumber not painted, visible and hidden mold

Ceratocystis/Ophistoma black mold group - see Cosmetic Mold

Cladosporium sp. / C. sphaerospermum;

Less common:

Aureobasidium pullulans; (more common on plywood sheathing)
Aspergillus sp.;
Penicillium sp.;

Trichoderma sp.;

May vary by wood species;
Varies by treated vs. un-treated lumber;
Varies by coated or un-coated lumber;
We find parasitic mold growth on top of cosmetic mold growth on some lumber, both un-treated and treated.

See Meruliporia Mold Photographs for a mold that causes structural damage.

Framing lumber, treated wood, visible and hidden mold

Ceratocystis/Ophistoma black mold group - see Cosmetic Mold

Aspergillus sp. and Penicillium sp. have been found growing parasitically on cosmetic molds on lumber, particularly common on treated lumber.

Cladosporium sp.;

Wood treated for insect or rot resistance, may vary depending on treatment chemicals.
Furniture, indoor wood, visible such as this Aspergillus sp. on a pine desk, and hidden mold

Cladosporium sp.;
Stachybotrys sp.;

Penicillium sp.;
Aspergillus sp;

Depends on wood species, wood coating; Check un-coated surfaces such as under bureau drawers and the under-side of chip board or particle board furniture such as game tables and pool tables. See Green Mold for photos of green mold on indoor cabinets & furniture.
Furniture upholstery, visible and hidden moldCladosporium sp.;
Stachybotrys sp.;
Aspergillus sp;
In addition to surface mold, mold growth inside of upholstered furniture may be present and may be detected by vacuum methods. See Black Mold  for photos of moldy upholstered furniture.
Glass surfaces indoors, visible and hidden mold Cladosporium sp.; Depends on deposition of organic debris;
Hardboard products such as Masonite, used for pegboard, paneling, or for works of art as a painting substrate    
Homasote & other fiberboard insulating board and sheathing products, mold, visible and hidden Aspergillus sp.;

Uncommon, found in flooded homes subject to extreme mold growth

lso see
SHEATHING Homasote & Other Board

HVAC equipment: air conditioner or heating system air handlers and blowers, especially where organic house dust and debris accumulate Cladosporium sp.;  
Insulation, asbestos pipe, visible and hidden mold Stachybotrys sp.;
Aspergillus sp.;
Mold growth depends on paint coating, fabric fibers (cotton wrap), and moisture exposure. See See Black Mold  for photos of mold on asbestos pipe insulation.
Insulating boards, styrofoam, urethane foam, others, visible and hidden mold    
Insulation, cellulose, visible and hidden mold None of our field samples have detected mold contamination in this material. We postulate that the fire retardant chemicals used on blown-in or loose-fill cellulose building insulation retard mold growth. The life expectancy of this mold resistance may be affected by time or by exposure to water. See Cellulose loose fill insulation
Insulation, fiberglass,in the fiberglass visible and hidden mold including both and on insulation kraft paper subject to wet conditions Penicillium/Aspergillus sp. inside of fiberglass insulation in floors, walls, attics, cathedral ceilings where leaks have occurred

Significant levels of mold contamination may be present but not visible to the naked eye, in insulation that has been wet or exposed to high moisture, or exposed to high levels of airborne mold from building demolition. Special insulation vacuum test methods are used.

Additional mold genera/species appear on foil or kraft-paper insulation facing.

See FIBERGLASS INSULATION MOLD

Insulation, foam board, visible and hidden mold Cladosporium sphaerospermum; Mold growth on closed-cell foam insulating board is invariably surface-only and appears to depend on the presence of organic dust or debris. May vary by type of foam and by foam board coatings such as foil or paper. See Foam Board Insulation
Insulation, sprayed icynene, visible and hidden mold We have not detected mold growth on this material Mold growth may be possible on icynene foam depending on its exposure to airborne organic dust and debris. See Mold in Foam Insulation
Leather clothing, shoes, leather furniture, visible and hidden mold Aspergillus sp.;  
Lumber, framing, visible and hidden mold, including cosmetic mold arriving on lumber from the lumber supplier or on lumber used in new construction    
Mattresses, not covered by other materials, visible and hidden mold  May vary by mattress cover fabric type, cotton vs. synthetic mix; mold growth inside of mattresses may be present and may be detected by vacuum methods.
Metal stud walls & metal stud wall cavities, visible and hidden mold Typical molds found on drywall or paneling;  
Metal surfaces, e.g. stainless steel kitchen sink, visible and hidden mold  Mold growth probably depends on the presence of food or other organic dust and debris
Mobile homes, visible and hidden mold in various locations associated with most common moisture and leak risks on these structures: wall cavities below windows, floors, subflooring, crawl area insulation, roof cavities   See MOBILE HOMES, DOUBLEWIDES, TRAILERS
Modular homes, visible and hidden mold in cavities and locations peculiar to modular home construction methods and due to leaks during transport of modular home units in wet weather   See MODULAR HOME CONSTRUCTION and see PANELIZED CONSTRUCTION & KIT HOMES
OSB, oriented strand board sheathing for roofs, walls, floors, subfloors, visible and hidden mold Stemonitis sp., Aspergillus sp., Ulocladium sp., Cladosporium sp., Pithomyces sp., Basidiomycetes, on occasion, Meruliporia incrassata. Photo of very moldy OSB subfloor from basement side
Also see SHEATHING, OSB.
Painted surfaces, wood, visible and hidden mold; painted masonry including brick & masonry block as well as poured concrete foundationsAspergillus sp.;
Penicillium sp.;
Yeasts;
Mold genera/species may vary by paint chemistry. See Green Mold and Red Mold.
Paneling mold, visible and hidden mold Aspergillus sp.;
Penicillium sp.;
Yeasts;

Varies by type of paneling, wood species, paneling coating, painted paneling, vinyl-covered paneling, and wood paneling.

See Hidden Mold Behind Paneling
See Red Mold for photos of moldy paneling.
See White Mold for photos of moldy solid pine paneling and wainscot.
See USING LIGHT TO FIND MOLD for tips on spotting hard-to-see light colored mold on wall paneling and similar surfaces.

Papers, files, file folders, newsprint, visible and hidden mold

In order from most-wet to less-wet:

Stachybotrys chartarum/ Stachybotrys sp.; less often, Memnoniella sp.;

Cladosporium sp./ C. sphaerospermum;

Aspergillus sp. / A. flavus, A. versicolor

 

Mold genera/species probably varies by paper chemistry, newsprint vs. cardboard, clay-coated vs un-coated papers, rag content

See SAMPLING DRYWALL

Pergo type laminated flooring products, visible and hidden mold Uncommon. Flooring that has been flooded needs to be removed where water has passed below.
Pine boards, solid pine wood used for trim, paneling, flooring, or subflooring with variation with subflooring age and exposure to moisture, and between painted or coated-sealed sides and un-finished (usually wall cavity) side, visible and hidden mold

Aspergillus sp. / A. flavus, A. versicolor

Trichoderma sp.;

Cladosporium sp.;

 
Plaster walls, ceilings, raw plaster & painted plaster, visible and hidden mold    
Plastic ceiling & wall covering materials   In areas subject to flooding & extreme mold growth conditions
Plywood, building roof sheathing, wall sheathing, plywood subflooring, furniture backs, bottoms, counters, cabinets, visible and hidden mold

Taeoniella sp., T. rudus, on plywood subfloor exposed to leaks such as at sliding entry doors.

Aureobasidium pullulans common in attics on roof sheathing;

Cladosporium sp., C. sphaerospermum, common on roof sheathing;

Varies depending on presence/absence of coating (e.g. painted plywood), and by level of moisture encountered.

Also see SHEATHING, Plywood

Porcelain surfaces, visible and hidden mold Cladosporium sp.; Mold growth probably depends on presence of organic dust and debris
Roof sheathing, OSB oriented strand board, visible and hidden mold Cladosporium sphaerospermum;
Aureobasidium pullulans;
 
Roof sheathing, pine boards, T&G, visible and hidden mold Aspergillus sp.;
Penicillium sp.;

Trichoderma sp., T. viride (green), and T. harzianum
Found in poorly vented and leaky attics of older homes; found in some attic knee wall areas on roof and floor sheathing;
See White Mold for photos of moldy tongue and groove roof sheathing.
Roof sheathing, plywood, un-treated, visible and hidden mold. Also see OSB sheathing discussed above.

Cladosporium sphaerospermum;
Aureobasidium pullulans;

Less common:
Aspergillus sp.
Penicillium sp.

Mold growth depends on moisture exposure from leaks and inadequate attic ventilation; See Brown Mold for photos of mold on plywood.
Shoes, cloth, vinyl, leather, visible and hidden mold Aspergillus sp.
Penicillium sp.
 
Stainless steel surfaces, visible and hidden mold uncommon Appears on these surfaces when also contaminated with soap, organic debris, and in extremely moldy conditions in buildings
Stereo speakers, visible and hidden mold on wood or cloth surfaces, also on paper materials such as speaker cones Aspergillus sp.;
Penicillium sp.;

Basidiomycetes;
Mold growth varies by material: cloth, wood, vinyl, metal
Subfloors in buildings, visible and hidden mold   See Hidden Mold in Flooring & Subflooring
Tile, asphalt flooring, visible and hidden mold We rarely find mold growth on this material except when the surface includes organic debris or dust.  
Tile, ceramic, bathroom, kitchen walls, visible and hidden mold Cladosporium sp.; Mold growth on ceramic surfaces depends primarily on the presence of organic debris such as soap film, skin cells, house dust.
Tile caulk, bathroom, kitchen walls, visible and hidden mold Cladosporium sp.;  
Tile grout, bathroom, kitchen walls, visible and hidden mold Cladosporium sphaerospermum;  
Tile, vinyl flooring, visible and hidden mold    
Trim, interior vinyl   typically on or in glue or organic debris on these surfaces
Trim, interior wood, visible and hidden mold including wood rotting fungus and even sprouting mushrooms indoors where wet conditions are common Aspergillus sp.;
Penicillium sp.;
Yeasts;
rare: Meruliporia incrassata
Varies by wood species, coating (paint, stain), and exposed vs. hidden surface.
Also see Also see ROT, FUNGUS, TERMITES.
Vinyl sheet flooring, visible and hidden mold; vinyl exterior siding Cladosporium sp.; Varies between upper surface and underside, flooring materials, paper, glue or adhesive, and presence of organic debris
Don't mistake algae on vinyl exterior siding for mold;
Wallpaper, visible and hidden wallpaper mold Stachybotrys chartarum, especially on hidden surface where leaks have occurred or in baths. See Black Mold  for photos of S. chartarum behind wallpaper.

Varies by age, wallpaper colors, pigments, dyes, and adhesive; some antique green wallpaper pigments interact with some molds to release arsenic.

Varies by material, paper, vinyl, fabric

Varies by coating, foil, paint, vinyl, plastic.

Varies by surface, room-side vs. wall-side of wallpaper may be completely different, or present only on the hidden side of wallpaper.

Wall sheathing, fiberboard, Homasote™ (also used as insulating board inside of building foundations), visible and hidden mold

Aspergillus sp;
Cladosporium. sp.;
Penicillium sp.;

Homasote™ and similar soft fiberboard materials are made of paper or softwood fibers. We have found significant mold growth only when the material was subjected to very wet conditions for a protracted period in basements or wall cavities.
See Hidden Mold in Wall Cavities

Wall sheathing, plywood, visible and hidden mold

Cladosporium. sp.;
Aureobasidium pullulans;

See Hidden Mold in Wall Cavities
Wall sheathing, OSB, visible and hidden mold Cladosporium. sp./C. sphaerospermum;
Aureobasidium pullulans;
See Brown Mold for photos of mold on basement OSB wall sheathing.
See Hidden Mold in Wall Cavities
Water heaters & other painted or porcelain coated steel jacketed appliances, metal surfaces Cladosporium. sp./C. sphaerospermum;  
Windows, interior side, visible and hidden mold Cladosporium sphaerospermum often found on window muntins subjected to water from condensation; many molds are deterred from window growth by exposure to light and UV. Varies by window material, wood, vinyl, metal, and by coating, paint, stain, un-finished.
Wood building sheathing, roof or exterior wall, visible and hidden mold.  

See Roof Sheathing
See Framing Lumber
See Hidden Mold Between Framing & Sheathing
See Wall Sheathing. See Meruliporia Mold Photographs and see Yellow Mold for a mold that causes structural damage. Also see ROT, FUNGUS, TERMITES

Wood framing lumber   See Lumber; Also see ROT, FUNGUS, TERMITES and see ROT, TIMBER FRAME
     

Notes to Table

1. We have been using special methods to test fiberglass building insulation for Penicillium/Aspergillus sp. in areas where the insulation has been wet or where insulation has been exposed to active mold growth such as over a wet crawl space or a moldy basement.

3. Some of the molds listed in this table, even though found indoors, are unlikely to be indicative of a growing mold reservoir of that genera/species. For example, we often find Cladosporium herbarium and certain Basidiomycetes such as Ganoderma sp./G. applanatum/G. tsuge in indoor air samples but we have not found these genera/species growing on building materials. Rather they enter in outdoor air.

In conclusion, this interesting table needs additional research with data provided by expert building investigators rather than self-collected data by individuals who spot first and sample first dark molds on building surfaces. Readers should see How to Look For Mold.

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