Additional Mold Information

Selected Microbial References

Fungal Sample Data Discussion

Mold Remediation Procedures

Review Criteria for Successful Mold Remediation

Mold Why Now?

My simple answer is --- Why not? Mold is an opportunistic degrader of organic materials. Get it wet and mold will likely grow. There are well over 100,000 species and strains of mold; many are very specialized and adept at living and reproducing under difficult conditions. Put sensitive people near it and they can get ill. And they can always get a lawyer if they feel some one else is at fault.

What’s Changed? Why Now? Here’s a quick list of thirty odd items that have changed in the last 25 years. Some relate to building construction and some to human behavior.

1. Better documentation of mold caused illnesses, better public awareness of the issues
2. 1990's Flooding in the Midwest and Texas and the resulting mold problems
3. People spend more time indoors now than ever before, increasing exposure time
4. Many people have compromised immune systems and our general population is older
5. Buildings are constructed with less ventilation for energy conservation
6. Houses now have considerably more plumbing and water sources to leak; 2 to 5 baths
7. Air conditioning houses are closed up in the summer and winter
8. More lawn irrigation systems now than in the past; moss growing on north side of houses
9. Building on the flood plain 1 foot above water table, building on filled in wetlands
10. Home owners often have no idea how to maintain their property; less handy now for repairs
11. Poor quality building materials, often failing and resulting in water leaks
12. Fly by night contractors, poor quality construction and lack of good oversight,
13. House money going into fancy looks and not quality construction; i.e., $6,000 jet tubs
14. Landscaping not completed to proper grade and drainage
15. Landscaping planters and borders directly adjacent to buildings holding rain and lawn water
16. Lawns that are way over watered
17. Using recycled or low quality (often moldy) building materials, such as wet moldy wood
18. The housing stock is growing older and older and is in need of important repairs
19. Building houses with 6 inch roof overhangs, roof drainage is next to the foundation
20. Cheaper aluminum windows used for years that sweat and get mildew growth
21. Fancy roof lines with more ridges, cuts and flashing for looks, more likely to leak
22. Plumbing quality has decreased and more pinhole leaks appear to be occurring
23. Icemakers that leak and go undetected for long periods of time
24. Higher insurance deductibles, owners trying to fix the water damage and not filing a claim
25. Flooding and mold disclosure now required on the building seller disclosure statements
26. Recent big law suit settlements and people know they can get repair response from landlord
27. Crawl spaces lack ventilation, incomplete vapor barriers, and seldom get inspected
28. Prior to 1999, Insurers had been making money on their investments, limited house review
29. Vapor barriers in crawl spaces are not complete and are often moved during crawl work
30. Period of high carpet use, carpet holds spores, carpet used in bathrooms and laundry
31. Rapid communication via the news media and Internet

Got Mold Problems?

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Mold can be a health hazard to many people and certainly a concern if identified during the real estate transaction. We want to make sure the deal closes and your clients can feel safe in their new home or office. We are qualified and experienced professionals who do it right.

Mold and Buildings Don't Mix

Concern about indoor exposure to mold has been increasing as the public become aware that exposure to mold can cause a variety of health effects including allergic reactions.

Mold can be found anywhere. Mold can grow on virtually any organic substance, as long as moisture and oxygen are present. There are molds that grow on wood, paper, carpet, foods, and insulation. When excessive moisture accumulates in buildings or on building materials, mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed.

There is a lack of agreement between researchers about what constitutes a "problem situation" and an overall lack of industry experience in interpreting microgiological laboratory data. Therefore, it is critical that the indoor air consultant be able to combine experience and knowledge of microbiology to evaluate laboratory results of samples collected from interior locations.

Initial Evaluation
The intial evaluation of a suspect mold problem requires a thorough review of the building including the HVAC system, suspect leaks, building materials, landscaping and suspect mold impacted areas. It is important to have a good understanding of occupant health issues and symptoms.

A typical air sampling strategy includes an outside air sample, a non-compliant area sample, and a complaint area sample. Air samples are analyzed for both viable fungus and total spores (non-viable). Surface samples will help identify specific genera in mold reserviors.

Data interpretation is complex and should only be done by trained professionals.

Mold Remediation
Every project is different, however, rapid response and repair of the water or humidity problem is critical. Non-porous surfaces can be cleaned and disenfected. Porous materials contaminated with mold must be replaced. Disinfection is not a substitute for removal of porous material as dead fungi remain allergenic and toxigenic.

Because of the health effects associated with elevated concentration of microorgranisms, remediation should be performed by competent individuals familiar with the precautionary measures required.

Post Remediation
Summit Environmental recommends that post remediation verification inspections be conducted. A thorough visual inspection of the area is completed along with surface and air sampling for microbial contaminants. The information will assist to document proper clean-up.

Twenty Actions for a Healthier Crawl Space

Crawl spaces are generally where the building meets the earth and are seldom given the attention they need. They are usually managed as “out of sight, out of mind”. Unfortunately, by the time Summit Environmental, Inc. is contacted, a problem has been identified and the crawl space is “unhealthy” or has become a mold amplification site. Crawl spaces will never be free of mold and bacteria, because they are ubiquitous to the earth; however, mold concentrations should be as low as possible.

A building owner’s objective should be to improve air quality in the crawl space as best practical. A crawl space generally has higher mold counts than the living area of the building. The issue of how high is too high is difficult to answer, even when specific types of mold are identified through sampling. Often quantitative microbial data is not available.

The following twenty items outline conditions or actions, which will improve the quality of the environmental air in the crawl space and in turn improve the air quality within the living envelope of the building:

I. Maintain good ventilation and low relative humidity. Make sure you have good ventilation and / or a dehumidifying system. Ventilation should consist of approximately one square foot of vent for every 150 square feet of crawl space. Make sure vents are not covered with foundation insulation.

II. Maintain a low (negative) pressure. A low (negative) pressure in the crawl space and a high (positive) pressure in the living area limits crawl space air from entering the living area.

III. Maintain a complete high quality vapor barrier over the soil. (See FHA requirements) Make sure no old wood scraps, paper, boxes, etc. are covered with the vapor barrier plastic and seal the edges and seams.

IV. Keep free of organic construction debris. No wood scrap, paper, boxes, etc.

V. Keep free of natural organic material. No roots, weeds, grasses, moss, etc.

VI. Keep free of insects and spiders. Spider webs can block vents and reduce ventilation and certain insects produce allergens and can damage wood.

VII. Keep free of mice, moles, rats, and other rodents. Mouse urine and feces create odors and can contribute to bacteria growth and rodents, in general, can cause physical damage.

VIII. Prevent animals from entering. Cats using a crawl space as a cat box can create a major mess.

IX. No standing water or muddy soil. There should be no outside water draining into the crawl space, gutter drain spouts, sprinklers, patio draining, etc. Water should always be directed away from the crawl space.

X. No supply water plumbing leaks. Leaking pipes, tubs, and shower pans all create major water problems in crawl spaces, including increased humidity, sub-floor rot, and increased mold and bacteria concentrations can also occur.

XI. No leaking drainage lines or toilets. Gray and black water releases into the crawl space are obviously a major problem and need immediate attention. Special clean up is needed for gray and black sewage releases.

XII. Contractors should clean up their debris and maintain the vapor barrier. Many crawl spaces have been compromised by plumbers, owners, and cable or telephone installers disrupting the vapor barrier and leaving wood cuttings and other trash.

XIII. Seal floor penetrations. Penetrations through the floor should be sealed to minimize air exchange between the house and the crawl space.

XIV. Keep HVAC system ducts sealed. Holes and cracks in ducts allow musty crawl space air into the HVAC system and decreases operating efficiency.

XV. No dead animals allowed. You would be surprised at the rodents, birds, frogs, etc., that are often found dead and decaying in crawl spaces.

XVI. No toxic insecticide / fungicide use. Do not use persistent toxic substances that can migrate into the house or HVAC system air.

XVII. Do not store household goods and cardboard boxes in the crawl space. Why keep anything of value in a damp musty crawl space.

XVIII. Keep planters and vegetation from holding moisture along the foundation. Some planter edging will hold or pond 2 to 3 inches of water along the foundation.

XIX. Surface grade should be sloped away from the foundation. Surface drainage should be at least a 6-inch drop per 10-foot distance.

XX. Monitor crawl space conditions at least twice a year. Inspect for insects, rodents, leaks, and check relative humidity on a regular basis; especially check after major rainstorm or a big snowmelt.

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