What is mold?
Mold is a type of natural fungus that feeds on wood and other plant material. Mold spores commonly float around in the air but become a problem only when they start to grow where they are not wanted, feeding on materials in our homes.
What makes mold grow in my home?
Mold needs moisture to grow, and can live on almost any surface, such as wood, wallpaper, paint, carpet, sheet rock, or insulation. It grows best when there is extra moisture from a leaky roof, leaky pipes, high humidity, or flooding. There is no way to get rid of all mold spores from your home, but you can control mold growth by keeping your home dry.
Does mold affect my health?
Most types of mold do not harm healthy people, but people who have allergies or asthma may be more sensitive to mold. Sensitive people may experience skin rash, running nose, eye irritation, cough, nasal congestion, aggravation of asthma or difficulty breathing. People with an immune suppression or underlying lung disease, may be at increased risk for infections from mold.
A small number of molds produce toxins called mycotoxins. When people are exposed to high levels of mold mycotoxins they may suffer toxic effects, including fatigue, nausea, headaches, and irritation to the lungs and eyes. If you or your family members have health problems that you suspect are caused by exposure to mold, you should consult with your physician.
When is mold a problem?
You know you have mold when you smell the "musty" odor or see small black or white specks along areas such ceilings and walls. If you notice mold or know of water damaged areas in your home, it is time to take action to control its growth.
Mold is often found in areas where water has damaged building materials and furniture from flooding or plumbing leaks. Mold can also be found growing along walls where warm moist air condenses on cooler wall surfaces, such as inside cold exterior walls, behind dressers, headboards, and in closets where articles are stored against walls. Mold often grows in rooms with both high water usage and humidity, such as kitchens, bathrooms, laundry rooms, and basements.
Should I sample for mold?
You don't need to sample for mold because in most cases you can see it or smell it. Even a clean, dry house will have some mold spores, but not enough to cause health problems. If you smell mold it may be hidden behind wallpaper, in the walls or ceiling, or under the carpet. If you suspect you have hidden mold be very careful when you investigate, protect yourself from exposure in the same manner as you would for a clean-up.
How do I clean up mold?
Follow these steps to clean up a moldy area. It's important to act fast, as mold damages your home as it grows. Clean it up as soon as possible.
How can I control mold growth in my home?
Dry out the house and fix any moisture problems in your home:
Stop water leaks, repair leaky roofs and plumbing. Keep water away from concrete slabs and basement walls.
Open windows and doors to increase air flow in your home, especially along the inside of exterior walls. Use a fan if there are no windows available.
Make sure that warm air flows into all areas of the home. Move large objects a few inches away from the inside of exterior walls to increase air circulation.
Install and use exhaust fans in bathrooms, kitchens, and laundry rooms.
Ventilate and insulate attic and crawl spaces. Use heavy plastic to cover earth floors in crawl spaces.
Clean and dry water damaged carpets, clothing, bedding, and upholstered furniture within 24 to 48 hours, or consider removing and replacing damaged furnishings.
Vacuum and clean your home regularly to remove mold spores.
Check around your windows for signs of condensation and water droplets. Wipe them up right away so mold can’t start to grow.
Renters and landlords can both help prevent indoor mold problems.
Renters need to operate the heating and ventilation systems to reduce water condensation. Renters need to notify landlords promptly, in writing, of any water leaks or moisture problems. If there is a water leak or moisture problem, it should be fixed by the landlord.
If you rent your home, you are covered by the Residential Landlord-Tenant Act. Understanding your rights and responsibilities as a renter can help you resolve problems. For informational recordings on residential landlord-tenant matters, call the State Attorney General's Office Consumerline at 1-800-692-5082, option 8.
Landlords are responsible for maintaining rental units, including fixing building problems such as water leaks and ventilation or heating defects which may lead to moisture problems. The Residential Landlord-Tenant act requires landlords to notify their tenants about the health hazards associated with exposure to indoor mold and ways to control mold growth in their dwelling units. Posting this information in a visible, public location at the dwelling unit property is allowed.
- King County Health Department-Indoor Air Quality and Mold Prevention Guidelines
- Mold - Print these frequently asked questions about mold. Available in English and Spanish.
- Brief Guide to Mold, Moisture, and Your Home, EPA - Order free copies of this guide through the EPA website. Available in English (publication number: 402K02003) or Spanish (402K03008)