Attic – ventilation and air movement

Attic mold

Mold in attic areas can be challenging at times in regards to determining the exact cause and source of mold growth. However, there are some common conditions that we routinely find during our Mold Investigations that contribute to mold growth in attics.

Roof Leaks

Penetrations in roof systems are common sources of water intrusion into attic spaces. Improper flashing, deteriorated rubber boot flashing, missing or improperly installed flashing around chimneys or other penetration points, and inadequate roof repairs are common causes of roof leaks. Also, water seepage occurs when the roof is beyond the end of its life span and failing. Water damage and mold growth is a common result of roof leaking conditions. Annual inspection of your roof by a roofing specialist and routine maintenance can prevent leaks in the roof system, reducing the likelihood of mold growth in your attic.

Inadequate Roof Ventilation

The lack of proper roof ventilation is a conducive condition to mold growth in attics. Without adequate ventilation, moisture laden air remains in the attic area, often times causing elevated moisture conditions at the roof framing and roof sheathing. During cold winter months, condensation can occur on the cold roof sheathing, creating elevated moisture conditions.
Another common cause of inadequate ventilation is when insulation is blown into the attic and care is not taken to prevent the insulation from blocking the soffit vents. Soffit vents are critical in a passive ventilation system in order to move the air from the lower portion of the attic (intake soffit vents) to the upper roof vents (exhaust vents). Adding additional ventilation ports or a powered roof vent can oftentimes improve and correct inadequate roof ventilation conditions.

Bath & Kitchen Exhaust fans vented into the attic

Exhaust fans should be vented directly to the exterior of the home. However, this often is not the case. When the exhaust fan is missing its exhaust duct or the duct has become separated, that exhaust air is vented directly into the attic space, oftentimes contributing to microbial growth.

Missing or inadequate attic insulation

Attic insulation not only is important in energy conservation, but proper insulation levels can also reduce the chance of mold growth in attics. As air travels up through the structure, insulation provides a barrier to slow the rate of conditioned air loss into the attic area. When an attic has missing insulation, the air movement increases significantly and that warm air can cause condensation conditions on cold roof sheathing. The moisture conditions resulting from such condensation is a catalyst for mold growth. Check your insulation and make sure that you have good and even coverage throughout the entire attic, especially at the lower North side areas.

Gaps or openings in ceilings

Unsealed openings in ceilings, around exhaust fans, can lights, speakers, etc. allow warm conditioned air to escape into the attic area. Sealing all penetrations in the ceiling can be an important preventative step in reducing mold growth in attics.

Finally, we frequently get asked, why is mold in an attic a big deal? While it is true that attic areas are not generally considered living spaces and air communication from upper attic areas to the living space below is relatively uncommon (in most normal situations), attic mold should still be a concern. Why? Because it is possible that if negative pressure conditions exist or occur in the home, air containing mold spores could potentially be drawn from that attic area into the living space. In addition, attic mold is usually an indication of other defects or conditions that could lead to costly repairs down the road. Such as water damage, Mold contamination in the finished living areas, wood destroying organisms and other moisture related conditions. Now go check your attic and if you see unusual staining or mold-like conditions, call a mold professional for a full assessment and appropriate testing.

by Craig Cooper, Mold Inspection Sciences

Mold Remediation Containment

Mold remediation HEPA Filtered Negative Air Machine

One of the main intents of an initial mold inspection is to identify whether or not you have a mold problem. This can obviously lead to one of two outcomes: 1) You do not have a mold problem and your concerns were alleviated through a thorough mold inspection and/or testing, or 2) You do have a mold problem and proper mold remediation should be performed. I don’t know about you, but I would be hoping for option one. But, unfortunately, a lot of people end up in situation number two. The next step to properly address the situation is to enlist a certified, competent remediation contractor to perform mold remediation (removal of mold) in the affected area. This can be a pretty in depth process, but for the sake of this article (and the next two to follow) we shall break it down into three basic steps.

Part I – Containment of the affected area

When a remediation project is initiated, the first step is to set up containment (isolation) of the affected area. One of the concerns when indoor mold is present is the resulting airborne mold spores. Containment will help control the spread of these spores, while assisting the remediation contractor in returning the affected area to normal conditions. The act of removing or disturbing a mold source tends to distribute large quantities of mold spores into the air. If proper containment is not utilized, this can affect adjacent spaces to the work area and cause cross contamination.

The first step to setting up containment of the work area is installing a HEPA Filtered Negative Air machine. This is a fan that is set within the work area which pulls air from the area which is typically exhausted outside of the structure via flexible tubing or ducting. Doing this will begin to draw any airborne mold spores away from the airspace eventually creating a negative pressure environment, which we will be discuss later in this article.

Step two is to install physical barriers in the work area. This is most typically done with the use of heavy plastic. The main goal when creating this physical barrier is to completely isolate the work area from any adjacent, non-affected areas. For example, if mold is present in one room of your home and the adjacent areas have not been affected, the room must be isolated. Depending on the layout, the doorway would be completely sealed with plastic. All HVAC systems or shared airways between other rooms would be taped or covered in plastic. All electrical outlets and light fixtures would be covered. In essence, any area that could allow air communication between the work area and other non-affected areas should be properly sealed.

Once step one and two are completed, a negative pressure environment should be created. A negative pressure environment simply means that the air pressure within the work space is less than the air pressure in the areas surrounding that space. This is achieved when the volume of air being pulled out of the space (through the negative air machine) is greater than the volume of air being pulled into the space. As a result of this negative air pressure within the work space, any mold spores that become airborne through the remediation efforts are being controlled, preventing them from affecting the adjacent spaces and flushing them away from the indoor environment which is necessary when attempting to return the area to normal conditions.

Once these steps have been completed, the remediation contractor would then begin Part II of a basic mold remediation project. Stay tuned for what happens next…

by Brandon Apple, Mold Inspection Sciences

1. Will the mold make me and my family sick?
2. Do I actually have a mold problem, or is it just “mildew”?
3. If I have a mold problem, will it be expensive to diagnose or remedy?
4. Is all mold toxic?
5. Is all mold dangerous?
6. What type of company should I use to inspect and test my home?
7. How do I know who I can trust?
8. Who is qualified to inspect and test my home?
9. If I am a renter, who should pay for the mold inspection and testing?

Most of the questions above can be answered by a qualified, mold inspection and testing professional.  One of the first and the most important steps is to find a qualified mold inspection and testing company.  Here is what I suggest if you believe you may have a mold problem.

1. If you see visible mold-like growth or believe a room has a mold problem, avoid that room if you can.
2. Find a qualified company to inspect and test your home or workplace.*
3. Follow the recommendations of the company as stated in their inspection report and perform any mold remediation work that they recommend.

*How do you find a “qualified” company?

1. Ask friends and colleagues for recommendations.
2. Search the Internet.  Look for quality company websites that are informative and don’t use scare tactics.
3. A qualified company will a) have a good record with the Better Business Bureau, b) carry quality certifications from organizations like the American Council for Accredited Certification (ACAC), c) carry General Liability Insurance and Professional Liability Insurance (also known as Errors and Omissions insurance).  The latter is the most important and differentiates the true professional companies from “fly by night” organizations., d) have good reviews and testimonials from past clients, and e) utilize an independent, accredited lab for their sample analysis.
4. Ask to see a sample mold inspection report.  Does the company do good work?  Is the sample report complete, easy to read, and contain color photographs?
5. Look for referrals from The Indoor Air Quality Association (IAQA) or The Amercian Council for Accredited Certification (ACAC)
6. Does the company answer their phone?  Do they respond to web and email inquiries in a timely manner?
7. Is the person you speak to on the phone professional?  Are they patient and do they spend time to answer your questions?

Try not to feel overwhelmed.  Take it one step at a time.  The key is finding the right company to help you.

Here are a few places to go to perform research for mold related issues:

• www.iaqa.org
• www.epa.gov/mold
• www.planetmold.com
• http://allaboutmold.wiki.zoho.com/
• www.moldsci.com
• www.emlab.com

by Michael Bains, President, Mold Inspection Sciences

When selecting a mold inspection company, be sure to ask, at minimum, the following questions:

1.  Do you also provide mold remediation or cleaning services?

In my opinion, it is a conflict of interest to perform both the initial investigation/testing AND profit from the cleaning/remediation of mold. It is in your best interest to use an unbiased and neutral third-party for your initial investigation and testing.  The bottom line is: your mold inspector should not profit from the discovery of mold.

2.   Can you provide me with a past client referral list or client testimonials? 

Quality companies value hearing back from their clients and they should have a long list of satisfied customers.  Many even obtain personal statements from past clients who endorse their services.  If the company you are considering cannot or will not provide you with past client testimonials, then consider continuing your search. 

3.    Are you a member in good standing with the BBB (Better Business Bureau)?

The BBB can be a great resource to locate quality, ethical and honest mold companies.  Look for companies that have no complaints and a solid rating.

4.   Are You Certified?

Most states do not require any formal certification or licensing to perform mold investigations and testing.  However, there are organizations that provide independent certifications for mold investigation and sampling. The ACAC is the best of those organizations.  The ACAC requires a minimum number of years of field experience, successfully passing a stringent certification exam, and obtaining continuing education credits annually.  Make sure your mold professional is certified by a credible organization.

5.    And finally, do you carry Professional Liability Insurance (Errors and Omissions insurance, commonly called E&O insurance)? 

Most quality companies carry general liability (GL) insurance.  However, E&O insurance is expensive and cost prohibitive for most mold inspection firms.   The vast majority of mold inspectors do not carry this form of insurance that provides you with a higher level of protection.

Best of luck with your search for a quality mold inspection company.  I hope these questions help.

by Craig Cooper, Mold Inspection Sciences

To properly asses the indoor conditions, we must first collect an outside control, or baseline sample. This is necessary because we always have to remember that airborne mold spores are everywhere, so even a home that does not have a mold “problem” will have some mold spores within the air. For a sample to be considered “normal” it should be somewhat consistent with the outside control sample taken that at that same day and time. In general indoor spore counts should be roughly 75% of the outdoor counts and usually proportionately similar in terms of spore types.

We do get asked all the time though “well, why can’t we just use averages from previous samples to determine a baseline?” Great question, and at first glance it does seem like a reasonable method, but in reality it just doesn’t work that way. Averages are used to some degree in the analysis of air samples, but an average is just that, an average. The spore types and concentrations in our environment can swing drastically due to multiple factors that influence our environment. Mold is a living organism, and therefore it reacts to its environment conditions. So, if it has been wet and rainy out and the mold sources are, let’s say happy, then they may not be actively sporelating and releasing mold spores into the air. On the flip side of that, when conditions are dry, mold sources typically begin sporelating in an effort to spread out and find additional water and/or food sources. On windy days, we sometimes see very high spore concentrations. And when there is snow on the ground, we will typically see very low spore concentrations.

As a result of all of these influencing factors, it becomes apparent that averages just do not give us enough information to properly assess indoor airborne mold conditions. To fully understand if there is a mold “problem” within a home, it is important to have as much information as possible. And a big piece of information that helps us do that, is analysis of airborne mold spore concentrations as compared to an outside control sample. If you believe you have a mold problem, consider engaging a competent and certified mold investigation specialist to perform a thorough mold investigation and proper mold sampling.

by Brandon Apple, Mold Inspection Sciences

Training is vocational schooling. When a student completes a training course, he/she earns a training certificate or diploma. The student owns the training certificate and can add it to his/her curriculum vitae. No further requirements are necessary.

Certifications are affidavits of industry knowledge – knowledge beyond a course curriculum. When an individual demonstrates knowledge, he/she earns a certification designation. The individual does not own the designation, but may renew it after meeting its requirements.

Accredited Certifications are professional credentials qualified and recognized by one of three independent organizations. Certification programs accredited by the Council of Engineering and Scientific Specialty Boards (CESB) must require verifiable field experience. ACAC certifications are accredited by the CESB.

Among other items, the ACAC mold certifications require:

• Minimum years of verifiable field experience;
• Difficult certification exams,
• ACAC unanimous board approval; and
• Re-certification every two years with a minimum of 40 continuing education credits

When looking to hire a professional mold inspector, look for a company and inspectors that have reputable licenses, certifications, and ones that belong to industry leading organizations like the Indoor Air Quality Association (IAQA).

by Michael Bains, President, Mold Inspection Sciences

The majority of our mold and moisture investigations are considered “non-invasive”.  This means that our inspectors do not cut open walls and ceilings, we don’t remove bathroom or kitchen fixtures, nor do we lift carpeting or flooring materials.  There are two primary reasons for this approach.  Number one, if there is hidden mold, we don’t want to cause airborne mold spore contamination by exposing and disturbing the mold.  Number two, performing invasive exploration can cause damage (intentional or unintentional) to a home.  But, sometimes to fully understand a mold problem, or to be able to fully remedy a mold problem, invasive exploration is necessary.  So, who should do it?

The best person to perform invasive exploration for mold is a mold remediation professional.  They have the tools and expertise to place a testing area under containment using specific engineering controls.  This containment will prevent the spread of airborne mold spores should mold be found during the exploration.

We will make the recommendation for invasive exploration for mold when we believe hidden mold is possible.  For example, if during a typical mold inspection at a personal residence, we find an actively wet wall in a bathroom.  We will recommend ambient mold air sampling and sometimes a wall cavity sample.  If both of those samples are negative, we will recommend that the wall be opened (invasive exploration for mold).  Since the wall is wet and sealed from the ambient air in the bathroom, it is possible that there is hidden mold in the wall even though the air sample was normal or negative.  Should mold be found in the wall during the exploration, it will need to be professionally removed.  If no mold is found, the source of water will need to be repaired, but no professional mold remediation is required.

Invasive exploration is also an integral part of professional mold remediation.  If for example, we definitively discover a mold problem under a kitchen sink, we will recommend invasive testing under, beside, behind, and below that cabinet to look for mold that we cannot see in our visual investigation.  This invasive exploration will continue to approximately 18 inches beyond the last visible mold growth and water damage.

Invasive exploration for mold is another important tool used in professional mold investigations.  It is generally used to collect secondary data and is not always required as part of a professional mold inspection.

by Michael Bains, President, Mold Inspection Sciences