Reporting on mold in crawl space

[Russell Truluck]

Does anyone have any good comments (wording) conerning reporting on "typical" mold in the crawl space on floor joists in the south?

[mnahrgang]

Observed a "mold like substance" in the crawl space (See Picture this section). Reccomend testing and remediation by a certified mold specialist.

[Bruce A. King]

- Floor Structure - inspected: yes
All framing and components are not visible due to ducts and insulation.
Floor joist type: standard wood framing construction.
Some mold-like substance on floor joists is common. Many times it is present before or during construction. When an unusual amount is noticed, recommendations are made in the summary section.

[Joe Funderburk, CMI]

Depending on the moisture content,

"Ambient moisture content greater than 20% was measured in the wood structures. No decay as a result of high humidity was observed, but light fungi growth did exist. Wood will decay at moisture levels > 28% and will support fungi growth at levels in the low-20s. It is recommended that a qualified individual take appropriate measures to eliminate the environment conducive to fungi growth. The services of a crawl space specialist and/or mold specialist should be considered to achieve the desired results. Options to reduce the moisture levels include, but are not limited to, elimination of water intrusion into the crawl space, increasing ventilation, installation of a vapor barrier, increasing the amount of vapor barrier, or installation of a humidistat controlled fan. Here's useful information from the EPA about fungi: http://www.epa.gov/mold/moldresources.html."

or

"There is a high moisture content in the wood structures inside the crawl space (28%+ moisture was measured in some areas). Wood will decay at moisture levels > 28% and will support fungi growth at levels in the low-20s. Moderate to heavy fungi was observed in many areas of the floor joists. Because of the issues with high moisture content in the wood structures that result in fungi growth, it is recommended that a qualified individual: 1) take appropriate measures to eliminate the environment conducive to fungi growth, 2) eliminate the environment that will cause the wood to decay. The services of a mold specialist and/or a crawl space specialist should be considered to achieve the desired results. Options to reduce the moisture levels include, but are not limited to, elimination of water intrusion into the crawl space, increasing ventilation, installation of a vapor barrier, increasing the size of the vapor barrier, or installation of a humidistat controlled fan. Here's useful information from the EPA about fungi: http://www.epa.gov/mold/moldresources.html"

or

"Moisture content in wood structures was measured at < 20%, but it could be much higher in the humid summer months. No decay as a result of humidity was observed, but a small amount of fungi was noted on floor framing. Wood will decay at moisture levels > 28% and will support fungi growth at levels in the low-20s. Options to reduce the moisture levels include, but are not limited to, opening foundation vents, increasing ventilation, installation of a vapor barrier or increasing the amount of a vapor barrier, or installation of a humidistat controlled fan. We recommend at a minimum that you monitor the conditions in the crawl space during the humid summer months and take the appropriate actions if fungi levels are not reduced. The services of a mold or crawl space specialist may be considered to achieve the desired result."

[James H. Bushart]

I have found the best benign description of mold to be "an organic substance that would be consistent with mold" followed by the recommendation for sampling and evaluation.

[wsiegel]

Let me ask you guys a question. Why are you so concerned with mold in a non living space area. I can underdstand the moisture problem and address that. You may even want to test inside the home to see if there could be a related problem. Unless you are promoting the "mold is gold" attitude, fungi in a non living area is usually not remediated. Stop the moisture and you stop the mold.

[Joe Funderburk, CMI]

I never recommend remediation. As I'm not a certified mold specialist, it's not my job to recommend remediation.

I do report the presence of mold (I prefer to say fungi) simply because some people freak out over it and I don't want to be on the witness stand trying to explain why mold in a non-living space is not a problem.

[Bruce A. King]

On many homes around here the crawlspace is connected to the living space via air return leaks in the crawlspace around the hvac equipment.

I have found many with 1 to 2 inch gaps at the large air return duct on the crawl unit. Two of these were not visible without a difficult crawl to the back of the unit and from only one angle.

Regular cheap duct tape sticks to everything except ducts.

[Brian A. MacNeish]

Originally Posted by jfunderburk

I do report the presence of mold (I prefer to say fungi) simply because some people freak out over it and I don't want to be on the witness stand trying to explain why mold in a non-living space is not a problem.

wseigel said: "Unless you are promoting the "mold is gold" attitude, fungi in a non living area is usually not remediated. Stop the moisture and you stop the mold (ed.-yes)"

Any large amount of mould should be remediated if it is any way connected to the living space, especially if people with allergies, etc. are to be moving in and living there.

The crawl space, although not a living area, is the most intimately connected area- more so than an attached garage or the attic - since there may be return air ducting under negative pressures running through it. (See previous post by bking) There will be many other hidden holes/gaps (wiring/plumbing/gas piping/ducting) that will allow air carrying volatile organic compunds (VOC's) given off by some fungi or fine, light fungi decompostion dust particles to enter the living space.

The upward movement of air is driven/aided by the "stack" or chimney" effect (light, bouyant air rising upward and leaving holes or open windows at the top of the house and is replaced by air coming in at the lower levels of the house of which the the crawlspace is one). Use of any larger exhausting bath fans, range hoods, downdraft stove fans or whole house cooling, attic ceiling mounted fans will cause negative pressures in the house and tend to draw more air from the crawlspace, not a desirable action when mould is resident there.

[David Nice]

Don't use the word "mold" report it as potential bioligical material.