With heavy rainfall comes a tremendous amount of moisture. Leaks and condensation increase, temperatures and warm drying daylight decrease.
These are optimal conditions for mold growth, both interior and exterior. As exterior mold spores explode in number some of them are bound to settle in our indoor environments. Here’s an overview from the EPA on Mold growth in the home.
So what can you do to reduce to likelihood mold will take hold?
I have some tips to minimize the conditions conducive to mold growth and maximize you and your family’s health.
Mold needs 3 conditions for optimal growth:
- The Right temperature. Some mold species can grow at low (below 50 degrees F) and other species at high (above 90 degrees F), but most common mold species that grow indoors grow ideally at 55-85 degrees F. Unfortunately this is the optimal temperature for human comfort. So it is unlikely you can keep your home at a temperature that is inhospitable for mold growth. So we will not concentrate on that.
- An organic food source. Different species of mold like to eat different things, but they all need something organic to munch on. Many mold species love cellulose, i.e. wood and paper. These are the natural composters and when it rains these species start to eat up all the fallen branches and leaves in the forest, as well as our yards emitting millions of spores that make their way into our homes. Inside our homes molds like to eat wood. This is what “dry rot” is, fungi usually consisting of 2 species, Ascospores and Basidiospores. Other species like to eat paper, such as cardboard boxes, books, and paper backed wallboard, such as sheetrock. Pennicillium/Aspergillus and Stachybotrys (colloquially known as toxic black mold) are often found on wet or moist paper. Cladosporium, the species most often found growing on windowsills and in bathrooms, can eat a variety of Biofilms (household dust consisting of epithelial cells (dead skin cells) insect parts, pet dander, natural fibers such as cotton and linen, etc.). Some mold food sources we cannot easily remove from our home such as framing lumber and wallboard, but others we can, such as cardboard boxes.
- This is the big one and the one I will be giving tips on below. Mold needs moisture. There is a common saying in our business: “Mold is the symptom, moisture is the problem”. Mold growth either needs liquid water or high humidity. Liquid water can come from condensation on windowsills and in bathrooms, or from leaks, either internal or external. Without liquid water mold will not become active unless the humidity is high, usually 60-80% RH depending on the species. When the humidity is high enough, mold can become active and grow by absorbing moisture directly from the air.
Here are some tips to reduce both food sources and moisture in your home and thus reduce the likelihood and amount of mold that may grow inside your home:
Let’s start outside. When it rains water can easily enter what we call the “Building Envelope”. It is very important to make sure your site drainage system is clear from debris and working properly to move rain water away from your home, foundation, and crawlspace.
- Clean the roof of any leave or other debris.
- Clear gutters
- Make sure downspouts are in good repair, not clogged, and properly attached any extensions or the site drainage system.
- Make sure all property drains are clear of debris and flowing freely.
Check the “Building Envelope” for possible sites of water intrusion, i.e. leaks.
- Window and doorframes are spots where water can intrude. Check all door and window frame caulking for cracks and gaps and repair where necessary.
- Inspect the sealant around roof penetrations. Repair where necessary.
- Check building siding for cracks, peeling paint, holes, etc. Anywhere water may be able to get in.
After a heavy rain walk around the entire house and look for standing water, and clogged drains. Look inside the crawlspace and make sure there is no hidden flooding. Carefully check the inside of the house, take a close look at the ceilings, around windows and doors, and walls for small leaks. Because all big leaks start out as small leaks! Check under sinks and around tubs and toilets to make sure there are no plumbing leaks adding moisture to the interior of your home.
Assuming there are no leaks and your drainage system is working well, what other sources of moisture can address?
Inside a home the occupants can produce a tremendous amount of moisture. On average each human occupant expires (breathes) and perspires (sweats) about 2 POUNDS of water into the air a day. Pets can also add to this moisture source. During the winter we often close out windows, as it is cold out, and most residential heating systems have no way of bringing in fresh air or ventilating out moist, stale interior air. Thus interior humidity can often increase to levels above 60%, which is ideal for mold growth.
So what can we do about Mold Growth?
- Monitor interior humidity. Small, portable humidity monitors are available for around $10-15 and can be placed around the home. If RH (relative humidity) is consistently above 65%, action should be taken. Ideally, interior RH should be between 45-55% RH. Below 40% RH mucous membranes start to dry out and can cause occupant discomfort.
- Open windows when practicable to help flush out moisture and other interior contaminants. Even 1 hour a day can make a big difference, although 3-4 hours is recommended.
- Run ventilation fans in bathrooms and kitchens to help exhaust excess humidity from cooking and bathing. Run fans in bathrooms for at least 20 minutes after bathing. Timer switches can be installed on most bathroom exhaust fans and are highly recommended.
- Wipe excess condensation from windowsills. Inspect windowsills often. Do not keep curtains closed as this can trap moist, cool air and promote excessive condensation.
The above tips can help reduce moisture sources, what can do we do about reducing mold food sources?
- Do not keep books, papers, or cardboard boxes in moist areas such as attics, garages, basements or crawlspaces. Attic and crawlspaces should not be used as storage areas, but if you must store items in a garage or basement, we recommend sealed plastic bins.
- Keep areas mold likes to grow clean and dry. This means cleaning dust (biofilms) from windowsills, baseboards, and doorframes. Vacuum carpet regularly with a HEPA vacuum. The recommendation is to vacuum and sweep one day per week PER OCCUPANT, including pets!
- Check behind drapes and furniture for hidden condensation and biofilms. Allow airflow to reach these areas by opening drapes often and moving furniture a few inches from walls, especially exterior walls that can become colder and promote condensation.
Also, trust your nose, that musty smell is a sure indication of active mold growth. That musty smell is caused by microbial VOC’s, airborne chemicals that are a metabolic by-product of mold digestion.
If you think you have a hidden source of mold, call a professional Certified Microbial Investigator for a full mold inspection. Excessive interior mold can cause structural damage to your home and its contents, as well as allergic and respiratory reactions in some occupants. Take heed and be diligent, and you can survive this hopefully wet winter relatively mold-free.
Kitchen Mold Removal
Are you concerned that black mold could be lurking in your kitchen, perhaps hiding in the cupboards? Not only is it unattractive, it can also cause respiratory problems for your family. The following guide can help you locate, prevent and destroy any black mold that has taken up residence in your kitchen.
Where to find black mold in the kitchen?
Black mold tends to grow in dark, damp areas, which means it could be festering in a kitchen cabinet or cupboard for a long time before you uncover it. For this reason, it’s vital that you identify the areas in your kitchen that are going to be most prone to mold growth. This will give you the necessary knowledge so that you can find the problem before it gets too bad. Places to check include the following:
- Underneath the kitchen sink. Check the cabinet bottom and the back wall where the sink pipes enter for dampness or past signs of water damage, such as bubbling or peeling surfaces. Even if black mold isn’t visible, it could be growing on the underside of the sink cabinet or behind the wallboard.
- Under the refrigerator. A leak from a water line to the icemaker or simple condensation collection underneath the fridge could create the optimum environment for fungal growth. If your kitchen flooring looks like it has suffered water damage or if there is standing water and mildew present, black mold could also be growing under the floorboards. Also, check any cupboards near the fridge to make sure there is no moisture damage.
- Cabinets above or next to wall mounted microwaves or oven hoods. Another common trouble spot is behind the cabinets that border microwaves and hoods. This is because moisture and condensation from cooking can accumulate in these cupboard areas, especially if ventilation is insufficient.
Kitchen mold prevention
Since prevention is key to black mold management in the home, now that you know your kitchen’s trouble spots you are better able to stop it from growing in the first place.
Begin by checking underneath the sink on a regular basis and fixing leaks immediately. Keep the sink cupboard area clean and neat so you can empty it out for a quick leak check regularly. If you are like many people and use this cupboard area for cleaning supplies, place the supplies in a handled carrier so you can quickly pull everything out. A good time to check is after you have been using the sink, such as after dishwashing. If there is a leak, it is likely going to be damp if you just drained the sink.
As for the fridge, it’s good practice to pull it out and dust the rear coils every one to two months, anyway. Simply pencil this chore into your home maintenance calendar. You can then use this opportunity to check beneath the fridge for leaks and to make sure water lines are attached and not leaking.
Finally, inspect the area around and under the cabinets, microwave, and hood after you use the oven or microwave. If you find a lot of moisture or condensation, chances are that you need to add a stronger fan or better ventilation to the kitchen.
Kitchen mold removal
Black mold can be tenacious when it comes to removal. Although you can often remove the visible black mold by yourself, there is likely hidden mold that you cannot find for removal as easily. The basic removal process is as follows:
Step 1: Testing Testing is done if there is signs of moisture but no obvious visual signs of fungal growth. Testing may also be done if there is light visible growth, since the remediation firm will need to determine the extent of the growth.
Step 2: Seal the infested area The home is sealed. This means that the area that has mold, in this case the kitchen, is sealed off from the rest of the house so that black mold removal doesn’t send spores into other areas.
Step 3: Identification and replacement The cause of moisture is identified and fixed. Otherwise, the mold will simply return if there is still a moisture source. This may mean the removal and replacement of cabinets and wallboard so they cleaning can occur under them.
Last step: Removal and cleaning The actual removal and remediation begins. The crew will use a disinfecting and cleaning solution that removes and kills the fungus. Stains from the black mold may be present on cabinets, but these can usually be painted over and repaired.
Summertime traditionally brings family trips, school vacations, as well as plenty of hot uncomfortable weather. Those sunny days, however, often come with high humidity and afternoon thundershowers — ideal conditions for annoying and potentially toxic mold.
It’s a pervasive menace that is poised each summer to grow and thrive in your house. Left unattended, fast-growing mold can cause damage that will cost in the thousands of dollars to eradicate or, worse, pose a dangerous threat to the health of your entire family.
“No one knows how many homes have mold behind the walls, but the best estimate is about 70 percent,” said Richard E. Gots, a doctor and founder of the International Center for Toxicology and Medicine, a biomedical consulting firm.
Gots’s estimate refers to mold that is at an “elevated level” and therefore should be addressed if the conditions exist for the mold to take hold and grow.
The Environmental Protection Agency sets levels for acceptable radon levels as well as a threshold for lead in the house or water supply, and states regulate termite inspections and control compliance. Yet there are no federal or state regulations that dictate a safe level of mold for a residential property.
D.C. Council member Mary M. Cheh (D-Ward 3) has been campaigning for several years to pass legislation that would require residential property owners, including landlords, to disclose the presence of mold in their apartment, condo or house. This legislation is still pending.
According to the District’s housing code, the Department of Consumer Regulatory Affairs (DCRA) inspectors cannot cite a homeowner for mold because the city considers mold to be “an environmental problem,” rather than a housing or safety issue. Mold, of course, is notoriously difficult to detect, and what may look like dangerous mold can only be legitimately determined under a microscope by a competent inspector or lab. Additionally, most homeowner insurance policies will not cover damage from mold — they consider it a “preventable” condition.
In reality, mold is a fungus that can grow anywhere moisture is present. Mold spores thrive in warm temperatures (77 to 86 degree Fahrenheit) and wherever there are damp conditions. Mold spores are in the air we breathe, and they can grow on any surface. In a house, mold can be found in ceilings and walls, under sinks, in drywall, hidden behind wallpaper or baseboards, in the ductwork or even on furniture and clothes. It can also grow outdoors under wood piles or mulch, gutters or abandoned trash.
Mold in a house can lay dormant until it gets the needed heat and humidity to grow and multiply. Additionally, it needs a food source, such as dust, dirt or some other organic debris.
While not everyone will react to this growth in the same way, those sensitive to allergic or toxic mold can develop alarming symptoms upon merely entering a contaminated room. The result can be a serious — even life-threatening — illness if not treated in time.
If you suspect that you’ve been exposed to mold — or begin to experience dizziness, fatigue, nausea, shortness of breath or other symptoms of illness — contact a mold specialist and have your property inspected as soon as possible. Licensed professionals will test the air quality of your house and take samples of the visual mold, which will be sent to a qualified lab for evaluation.
The EPA provides helpful information in its publication “A Brief Guide to Mold, Moisture, and Your Home” at www.epa.gov/mold/moldguide.html . And the Centers for Disease Control and Prevention focuses on the health hazards of mold exposure and provides recommendations for removing mold exposure at www.cdc.gov/mold/dampness_facts.htm#note .
In addition to the traditional methods for eradicating mold (such as using chemicals or chlorine bleach and physically removing infected surfaces), there is a new, enzyme-based alternative. Previously used as a protective spray for fruits and vegetables, it is now available for home use.
Jenn Sherwood, manager of Green Home Solutions of Maryland, says that the enzyme spray is a cost-effective, time-saving and environmentally responsible way for homeowners to eradicate mold. The process uses a “fogger,” which emits a fine spray that is able to penetrate most porous surfaces (such as drywall) or even non-visible areas — behind walls or inside insulation. This method of eradicating mold often eliminates the need to remove and replace the existing material.
The EPA regards this spray as nontoxic to humans or pets and harmless to both surfaces and belongings in the home. The enzyme works by creating a bond with the mold spore, and then breaking it down from the inside. As a result, the mold is chemically altered into a particle that is no longer allergenic, toxigenic, or able to reproduce other spores. This treatment can cost from one-third to one-tenth less than the cost of traditional methods.
Given that your insurance company may not cover mold damage, it’s important to take immediate action.
Here are three easy steps to help prevent mold when you go on vacation:
●Check for areas where water could accumulate — such as around windows, doors, bathroom leaks, kitchen sinks and washing machines.
●Clean surfaces of oil, soap, dust and dirt. Those materials are a feeding ground for mold when moisture is present.
●Set the temperature inside the house in the low 70s, if possible. If you suspect humidity, set a dehumidifier to keep the moisture level below 60 percent. In your closet, place a hanging moisture absorber (such as Damp Rid) that will trap excess humidity and eliminate musty odors.
Sandy Gadow, a freelance writer and author of “The Complete Guide to Your Real Estate Closing,”
Prevent water damage and mold growth
Leaves, sticks, and debris can become a problem for your rain gutters. Rain gutters typically allow the removal of water away from your home or building. In this instance, the blockage within the rain gutter allowed water to overflow and deposit near the front door of the unit. If left untended, the backup within the gutter would allow the water to impact the structure and possibly cause water damage inside the home. Water damage and mold growth inside your home can be prevented by regular maintenance of the rain gutters during this El Nino rainy season.
Do your best to observe the signs of a failing rain gutter and prevent water damage:
- Loose or detached down spouts
- Bent or broken sections of the main gutter
- Excessive debris (including leaves and dirt)
- Improper slope and grading of the gutters
- Overflowing water
Norovirus (bacteria) has sickened 80 Boston College students who ate at a nearby Chipotle restaurant, state health officials said Tuesday.
“Initial testing conducted by the State Public Health has shown the presence of norovirus,” the health department said in a statement.
Although many of the students said they feared they’d been struck with the same E. coli bacteria that made 52 people in nine states sick this fall after eating at Chipotle restaurants, experts said the pattern of illness didn’t look like E. coli.
“Health officials in Boston believe this is likely a norovirus, which seems consistent with the pattern, in our estimation,” Chipotle spokesman Chris Arnold told NBC News.