If you see mold or smell mold you pretty much have mold.
Most molds are black in color.

Testing for mold can be a waste of money and time. The key to the mold is determining the cause. Marko E. Vovk is a CIE (Certified Indoor Environmentalist) and a BSE (Building Science Engineer) who specializes in moisture mapping, moisture surveys, and forensic moisture evaluations. Marko E. Vovk is also the Co-Author ofTHE ILLUSTRATED MOLD HANDBOOK. Please refer to the moisture mapping section of this web site for additional information.


Moisture Mapping Investigation Fungal Sampling
IAQ APP Aggressive Particle Profiling
Thermography Expert Witness
Psychrometrics Dew Point Projections
Odor Testing Building Science
Indoor Air Consultations Residential Forensics
Mold Laboratory Analysis Microbial Assessments
Digital Imaging Mold Investigations
HVAC Diagnostics Combustion Analysis


Introduction to Molds
Molds are simple, microscopic organisms, present virtually everywhere, indoors and outdoors. (You cannot kill all molds.) Molds, along with mushrooms and yeasts, are fungi and are needed to break down dead material and recycle nutrients in the environment. For molds to grow and reproduce, they need only a food source – any organic material, such as leaves, wood, paper, windows, boxes luggage or dirt and moisture. The paint or dust on your basement walls is all mold needs to grow. Because molds grow by digesting the organic material, they gradually destroy whatever they grow on. Sometimes, new molds grow on old mold colonies. Our Cleveland microscapist has taken photos of mold growing on a live dust mite. (A microscopic dust mite can be seen in the book “The Illustrated Mold Handbook written by co-author Marko E. Vovk.) Mold growth on surfaces can often be seen in the form of discoloration, frequently green, gray, brown, or black but also white and other colors.
Molds release many microscopic spores, which travel through the air. When excessive moisture or water accumulates indoors, mold growth will often occur, particularly if the moisture problem remains undiscovered or un-addressed. There is no practical way to eliminate all molds and mold spores in the indoor environment. The way to control indoor mold growth is to control moisture.
Basic Mold Cleanup
The key to mold control is moisture control. It is important to dry water damaged areas and items within 24-48 hours to prevent mold growth. If mold is a problem in your home, clean up the mold and get rid of the excess water or moisture. Fix leaky plumbing or other sources of water. Wash mold off hard surfaces with detergent and water, and dry completely. Absorbent materials (such as ceiling tiles and carpet) that become moldy may have to be replaced.

Downloads provided in PDF version on the page.

Ten Things You Should Know About Mold

  1. Potential health effects and symptoms associated with mold exposures include allergic reactions, asthma, and other respiratory complaints.
  2. There is no practical way to eliminate all molds and mold spores in the indoor environment. The way to control indoor mold growth is to control moisture.
  3. If mold is a problem in your home or school, you must clean up the mold and eliminate sources of moisture.
  4. Fix the source of the water problem or leak to prevent mold growth.
  5. Reduce indoor humidity (to 20-40%) to decrease mold growth by: venting bathrooms, dryers, and other moisture-generating sources to the outside; using air conditioners and de-humidifiers; increasing ventilation; and using exhaust fans whenever cooking, dishwashing, and cleaning.
  6. Clean and dry any damp or wet building materials and furnishings within 24-48 hours to prevent mold growth.
  7. Clean mold off hard surfaces with water and detergent, and dry completely. Absorbent materials such as ceiling tiles, that are moldy, may need to be replaced.
  8. Prevent condensation: Reduce the potential for condensation on cold surfaces (i.e. windows, piping, exterior walls, roof, or floors) by adding insulation.
    In areas where there is a perpetual moisture problem, i.e. by drinking fountains, by classroom sinks, or on concrete floors with leaks or frequent condensation, do not install carpeting.

Moisture Control

Water in your home can come from many sources. Water can enter your home by leaking or by infiltrating through basement floors. Showers or even cooking can add moisture to the air in your home. The amount of moisture that the air in your home can hold depends on the temperature of the air. As the temperature goes down, the air is able to hold less moisture. This is why, in cold weather, moisture condenses on cold surfaces. For example, drops of water form on the inside of a window. This moisture can encourage biological pollutants to grow. Please refer to our MOISTURE section for additional information pertaining to humidity, dew points, and forensic moisture mapping.

There are many ways to control moisture in your home:

  • Fix leaks and all moisture infiltration conditions. If water is entering the house from the outside, your options range from simple landscaping to extensive excavation and waterproofing. (The ground should slope away from the house. Generally, one inch drop per foot of slope.) Water in the basement can result from the lack of gutters or a water flow toward the house. Water leaks in pipes or around tubs and sinks can provide a place for biological pollutants to grow.
  • Put a plastic cover (vapor barrier) over soil in crawlspaces to prevent moisture from coming in from the ground. Crawl spaces should be conditioned and not vented to the exterior.
  • Use exhaust fans in bathrooms and kitchens to remove moisture to the outside. Vent your clothes dryer to the outside.
  • Turn off certain appliances (such as humidifiers, ventless heaters, ventless fireplaces, negative air machines, or kerosene heaters) if you notice moisture on windows and other surfaces.
  • FURNACE HUMIDIFIERS CAN RUIN YOUR HOME AND CAUSE MOLD TO PROLIFERATE. (Furnace humidifiers make mold remediation companies rich.)
  • Use dehumidifiers and air conditioners to reduce moisture in the air, but be sure that the appliances themselves do not become sources of biological pollutants.
  • Balance your heating system and seal all return air ducts.
  • Seal your sump pump pits with covers that are 100% sealed.
  • Do not install exfiltration negative air machines that claim to purify your homes air. (Most of these come from Canada. The Canadians are ripping us off with these glorified non-condensing dehumidifiers. These things can also create negative pressure and cause carbon monoxide problems.)
  • Do not allow HVAC systems to draw return air from the basement.
  • Do not use attic fans unless they are properly installed.
  • Do not vent dryer vents into attics, garages, or crawl spaces.
  • Raise the temperature of cold surfaces where moisture condenses. Use insulation or storm windows. (A storm window installed on the inside works better than one installed on the outside.) Open doors between rooms (especially doors to closets which may be colder than the rooms) to increase circulation. Circulation carries heat to the cold surfaces. Increase air circulation by using fans and by moving furniture from wall corners to promote air and heat circulation. Be sure that your house has a source of fresh air and can expel excessive moisture from the home.
  • Perform combustion analysis on all gas-fired systems to make sure that proper draft and combustion exists.
  • Make sure the fireplace, hot water heater, and furnace are not spilling or back drafting.
  • Pay special attention to carpet on concrete floors. Carpet can absorb moisture and serve as a place for biological pollutants to grow. Use area rugs, which can be taken up and washed often. In certain climates, if carpet is to be installed over a concrete floor, it may be necessary to use a vapor barrier (plastic sheeting) over the concrete and cover that with sub-flooring (insulation covered with plywood) to prevent a moisture problem.
  • Moisture problems and their solutions differ from one climate to another. The Northeast is cold and wet; the Southwest is hot and dry; the South is hot and wet; and the Western Mountain states are cold and dry. All of these regions can have moisture problems. For example, evaporative coolers used in the Southwest can encourage the growth of biological pollutants. In other hot regions, the use of air conditioners, which cool the air too quickly, may prevent the air conditioners from running long enough to remove excess moisture from the air. The types of construction and westernization for the different climates can lead to different problems and solutions.
  • Avoid double vapor barriers in attics.
  • Avoid vinyl wallpaper on exterior walls.
  • Avoid using vapor barriers on finished foundation walls.
  • Install drainage space, drainage plane, air vents, and weep holes in all brick installations.
  • Avoid installing sprinkler heads next to foundations.
  • Avoid using recessed or can lights in cathedral ceilings.
  • Avoid installing vapor barriers being drywall during construction.
  • Wood siding should be back primed and installed on firing strips.
  • EIFS requires a double drainage place prior to installation.
  • Frog, lily, or fishponds next to foundations are a bad idea. These same people put lawn ornaments in their front yards.
  • Swimming pools and hot tubs are for outdoors.
  • Keep the indoor plant life to reasonable numbers, like 5-7 total plants for the home.
  • Long showers on cold winter days will cause condensation conditions in your home.




The following are several sample report samples in PDF format that you can open or even download for later reading.
EPA Brief Guide to Mold / 270 KB / 20 PAGES
Click to view online. Right -click to Save-As
Click to view online. Right -click to Save-As
New York City Remediation for Mold / 122 KB / 20 Pages
Click to view online. Right -click to Save-As
Marko’s Mold Remediation long version / 474 KB / 40 Pages
Click to view online. Right -click to Save-As
Marko’s Mold has always been their guidelines / 19 KB / 1 Page
Click to view online. Right -click to Save-As
MARKO Sample Mold Report for ice dams / No mold samples taken / 10 pages
Click to view online. Right -click to Save-As
MARKO Sample Mold Report moisture in crawl space causes attic mold / Several mold samples taken / 10 pages
Click to view online. Right -click to Save-As
MARKO Sample Mold Report caused by sump pump / No mold samples taken / 10 pages
Click to view online. Right -click to Save-As
Sample Mold Mini Inspection Report / Three pages
Click to view online. Right -click to Save-As
Controlling Moisture Guide / 161 KB / 8 pages
Click to view online. Right -click to Save-As
  The above documents are in Adobe PDF format.
If you don’t have the Acrobat Reader you candownload free from Adobe.


Moisture on Windows


Your humidistat is set too high if excessive moisture collects on windows and other cold surfaces. Excess humidity for a prolonged time can damage walls, especially when outdoor air temperatures are very low. Excess moisture condenses on window glass because the glass is cold. Other sources of excess moisture besides overuse of a humidifier may be long showers, running water for other uses, boiling or steaming in cooking, plants, and drying clothes indoors. A tight, energy efficient house holds more moisture inside. You may need to run a kitchen or bath ventilating fan occasionally, or open a window briefly.
The American Society of Heating and Air Conditioning Engineers (ASHRAE) recommends these maximum indoor humidity levels.
Outdoor Recommended Indoor Temperature Relative Humidity

+20 F. 35% max
+10 F. 30% max
0 F. 25% max
-10 F. 20% max
-20 F. 15% max

TIP: We recommend all homes have a basement dehumidifier.
TIP: Unplug your humidifier; do not use ventless fireplaces or ventless heating units.
Tip: Balance your heating system and seal your sump pump pits.
For more information on moisture control, please go to the BUILDING SCIENCE section of this web site.

Can mold be toxic? Some molds can produce toxic substances called mycotoxins. Airborne mycotoxins have not been shown to cause health problems to occupants in residential or commercial buildings. The health effects of breathing mycotoxins are not well understood and are currently under study.

High or chronic airborne exposures, typically associated with certain occupations like agricultural work, have been associated with illnesses, although these are rare. More is known about eating mycotoxins (from humans and animals consuming moldy foods or feed) and the resulting health effects than is known about breathing mycotoxins.
What is “black mold”? The news media often refer to “black mold” or “toxic black mold”. It has usually been associated with the mold Stachybotrys chartarum, a type of greenish-black mold commonly associated with heavy water damage. Known health effects are similar to other common molds. It has been inconclusively associated with more severe health effects in some people. While there are only a few molds that are truly black, many can appear black. Not all molds that appear to be black are Stachybotrys.

MARKO E. VOVK calls black mold the “THE HOLLYWOOD MOLD”. Why are we concerned about mold? Small amounts of mold growth in workplaces or homes (such as mildew on a shower curtain) or workplaces are not a major concern, but no mold should be permitted to grow and multiply indoors. When molds are present in large quantities, they may cause nuisance odors and health problems for some people. Mold can damage building materials, finishes, and home furnishings. Some molds can cause structural damage to wood.

How do molds affect people? Most people will have no reaction at all when exposed to molds. Allergic reactions, similar to common pollen or animal allergies, are the most common health effects for individuals sensitive to molds. Flu-like symptoms and skin rash may occur. Molds may also aggravate asthma. Fungal infections from building-associated molds may occur in people with serious immune disease but this is very rare. Most symptoms are temporary and eliminated by correcting the mold problem in the home.

Who is affected by exposure to mold? For those who are affected by mold exposure, there can be a wide variation in how they react. People who may be affected more severely and quickly than others may include:
• Infants and children
• Elderly people
• Pregnant women
• Individuals with respiratory conditions or allergies and asthma
• Persons with weakened immune systems, e.g. people with HIV infection, chemotherapy patients, or organ or bone marrow transplant recipients, autoimmune diseases.

Those with special health concerns should consult their doctor if they are concerned about mold exposure. The symptoms that may seem to occur from mold exposure can also be due to other causes such as bacterial or viral infections, or other allergies.
What should I do if I see or smell mold in my home? The most important step in solving a mold problem is to identify and fix the moisture sources that caused the mold growth. For small mold problems, use detergent and water to wash mold off hard surfaces and dry completely. Porous or absorbent materials (such as ceiling tiles, wallboard, and carpeting) that become moldy should be replaced. If you do not see mold growth, but notice a musty odor, mold may be growing behind water-damaged materials, such as walls, carpeting, or wallpaper. Persons cleaning mold should wear gloves, eye protection and a dust mask or respirator to protect against breathing airborne spores. N95 dust mask or respirator may be purchased in hardware stores. If you have health concerns, you should consult your doctor before doing any mold cleanup.

Should I test my home for mold? Probably not. It should not be your first step. Your first step should be to have your home inspected for moisture, humidity, and building science conditions. Marko E. Vovk is a building science engineer who specializes in forensic moisture investigations.

Please refer to the MOISTURE TESTING section of this web site for additional information. Testing for mold is expensive, and you should have a clear reason for doing so. In most cases, it is not economically practical or useful to test for mold growth on surfaces or for airborne spores in the home. Testing also tells you little about where mold is located and how to clean it up. In addition, there are no standards for “acceptable” levels of mold in buildings, so when testing is done, it is usually to compare the levels and types of mold spores found inside the home with those found outside the home. If you know you have a mold problem, it is more important to spend time and resources to get rid of the mold and solve the moisture problem causing the moldy conditions rather than to test for the mold problem.


fungal reservoir
Mold growing
fungal amplification
Mold growth in one spot
Mold all over
fungal or microbial proliferation
Mold report
microbial essay
Mold report
Nasty stuff Bio-Growth
OH MY GOODNESS a lot of BioGrowth
Mold in vacant home VBS Vacant Building Syndrome or VHS Vacant Home Syndrome
Inside the wall interstitial
Black Mold toxigenic fungal reservoirs (Strictly for Hollywood people)
Sick from Mold hypersensitivity, immune compromised, sensitize, etc.
Mold test bulk swab, tape lift, slide
Mold test air spore trap, viable test, non-viable test, Air-O-Cell,
Anderson Impact Plate
Dust testing APP aggressive particle profiling, laser particle testing
Bubbling Paint stalagtosac
Its raining in my attic
hydrick buffer capacity has exceeded and condensation is occurring