Where Does Asbestos Hide in Homes? (And What to Do if You Find It)
Asbestos fibers are colorless, tasteless, and hard to see. They can also be deadly if people inhale them in large quantities over time. The advantages of using asbestos for construction were so well-known that it became a practical ingredient in virtually all kinds of building materials. These Asbestos Containing Materials (ACM) were widespread, in use all over the country, for decades. Only in the 1970s did people begin to realize the harm that loose (friable) or airborne asbestos causes. With the following information, homeowners can determine where they are most likely to find asbestos in their homes, and if the material poses a threat, what you can do about it.
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Roofing & Siding Shingles
Asbestos was a popular component in roofing and siding for much of the 20th century. Its ability to prevent the spread of fires lead to its use in a variety of roofing and siding products, including:
The way that homeowners can handle asbestos in roofing or siding depends mostly on the condition. Because asbestos has not been in use for more than 30 years, it is likely that any roofing or siding product containing asbestos is nearing the end of its lifespan. Assuming the materials are in good condition, they may not necessarily need to be removed immediately. Unfortunately, breakdown over time increases the likelihood that fibers will escape.
Homeowners should take extra care when maintaining roofing or siding that contains asbestos. A cracked shingle or damaged underlayment can shed fibers which are easy to breathe in. Disrupting them by removing materials can create a situation with significant risk for others in the area. For repairs or replacement, people should consider hiring a professional with experience in asbestos abatement. A regular roofing contractor may not have sufficient experience to manage the project without risking themselves or the home’s residents.
Attic & Wall Insulation
Asbestos was a common ingredient in insulation up until 1990. Homeowners with properties built prior to this date should consider the potential for asbestos in various types of insulation, including:
- Insulation on hot water pipes and hot water heaters
- Batt-style insulation
- Loose fill or vermiculite insulation
Some types of insulation were made of asbestos specifically, resembling popcorn. Others were contaminated by it. For example, vermiculite is another type of mineral that breaks into small flakes. People use it for insulation and sometimes in the garden. A particular source of vermiculite in Montana was highly contaminated with asbestos. As such, any insulation coming from that source is likely to contain asbestos as well.
When it is hidden behind walls, asbestos insulation may not pose much of a health risk to homeowners. People can minimize the hazard by sealing air leaks around walls and roofing to help keep the insulation in good condition. The risk increases when people decide to add or replace insulation, or replace other parts of the home that connect to the insulation. In this case, homeowners should call an asbestos abatement expert to remove the existing insulation and decontaminate the space.
Manufacturers also added asbestos to drywall components as a way to make it stronger without increasing the total weight. Drywall is typically made primarily out of gypsum, a type of soft, white stone that is easy to mold into a specific shape. Building companies used drywall with asbestos from the 1930s until late in the 20th century. Although the major concern for asbestos in drywall is for the panels themselves, asbestos was also added to joint compound used to seal the joints together and patch holes. As such, homeowners with drywall that does not contain asbestos may still have concerns to address. It is safe to assume that any drywall installed prior to 1990 has some asbestos.
Like other building materials, asbestos in drywall is most likely to be an issue when it is disturbed. For example, a homeowner drilling holes into the wall to hang a picture or brackets for a television may upset the fibers inside. Similarly, people who remove the drywall so that they can change the layout of a room may accidentally inhale the fibers. Wearing a snug-fitting mask rated to filter out asbestos helps to prevent immediate exposure. Otherwise, people may need to wear special clothing and decontaminate before they enter other parts of the home.
Because it was useful in blocking sound and heat, asbestos was a popular component in paints for ceilings and roofing. The best way to identify paint containing asbestos is to evaluate these factors:
Paint with asbestos is likely sprayed on the ceiling, usually on a textured ceiling that could not be painted easily with a roller. It was often added as a layer of protection under other roofing materials. The color can also reveal it, as asbestos paint is almost always white, gray, or silver.
The last indicator is the age. Paint applied to the ceiling during the 1960s to the 1980s usually contains asbestos. As such, people should avoid using any leftover paint products that date from this period.
The solution lies in preventing the fibers from falling down from the ceiling. Homeowners dealing with lead-based paint have similar options, typically in the form of encapsulation. This process involves spraying an additional layer of a special kind of paint on the surface to completely cover the old one containing asbestos and to prevent chipping or flaking.
There are two types of ceilings that may contain asbestos: ceiling tiles and popcorn ceilings. These two styles are quite dated for a modern audience, but they filled a specific purpose of durability and noise control. Asbestos was the primary ingredient providing these benefits. Vermiculite sprayed onto the ceiling and then covered with paint containing asbestos hid signs of damage and looked trendy for the time. Anyone with ceilings like these can assume that asbestos is there, even if it is covered under layers of paint.
The texture of the popcorn ceiling can make it difficult to repaint or replace. Over time, the pieces of vermiculite can loosen or drop off, releasing fibers into the air. Homeowners who attach things to the ceiling, such as hooks, can disturb the asbestos that way as well. Attempts to encapsulate the ceiling must be done by spray, as a roller can shift the texture. Anyone doing this on their own must wear a mask or other safety gear to prevent inhalation. People who have a textured ceiling may want to remove it in favor of something more modern-looking, but this will most likely require an asbestos abatement professional.
Almost any component of a fireplace, wood-burning stove, or chimney could conceivably contain asbestos. Asbestos was popular for its ability to guide heat in the right direction, which means manufacturers and installers used it in:
- Chimney insulation
- Cement to patch cracks
- Textures and decorations for gas-burning fireplaces
- Items attached to a wood-burning stove
The widespread use of asbestos means that most aspects of a fireplace built before 1990 are likely to have some asbestos in them. Although homeowners may not need to replace it unless it needs repair, they might still want to collect samples from their fireplace for testing.
Testing is usually the best way to identify asbestos fibers in a fireplace or chimney, as they are not particularly easy for homeowners to access. When scheduling regular maintenance for the fireplace, people may want to hire a company that has experience working around asbestos. If the fireplace, stove, or chimney need repair, replacement by a qualified professional is likely the safest way to minimize risk and neutralize the problem.
Older Consumer Products
Although many people know that asbestos was a popular building product for much of the 20th century, its use dates back thousands of years. As such, it is no surprise that millions of consumer products contained asbestos, as people were accustomed to using it and thought it would be safe.
Just as ancient communities appreciated asbestos for its ability to hold heat without bursting into flames, modern people used asbestos in wicks for oil lamps or various home appliances. The wires around cables for electrical equipment were often lined with asbestos, which could shed with wear and tear on the wire. Asbestos was a prominent feature in a variety of paper products, as well as talcum powder. The powder in particular has been hazardous because it is already loose and typically applied to the face. People can avoid most of these hazards by replacing old appliances with models made in this century, and discontinuing the use of any old or vintage skin products.
Vinyl is a plastic compound that asbestos made harder to chip and better for high-traffic use. It was a common element in a variety of vinyl products, such as:
- Floor tiles
- Sheet flooring
Vinyl flooring with asbestos was extremely durable, which means that houses with this flooring from the 1970s may still have it. Removing wallpaper or tiles using heat or a scraping tool pose a threat, as the fibers can become airborne during this process. Someone who wants to remove the flooring in order to restore the hardwood underneath it will likely need to call a professional for assistance. Additionally, people can likely install new flooring on top of asbestos tiles, but they should avoid sanding it first.
Boilers & Water Heaters
It is unlikely that homes will have a boiler or water heater containing asbestos parts, but not impossible. Typical boilers and water heaters have a lifespan of about 10 to 20 years, depending on the type and upkeep. With good maintenance, however, boilers have been known to last up to 50 years, which means that older ones could present a risk for asbestos exposure. As with fireplaces, many aspects of water heating worked well with asbestos, including:
- Insulation around pipes
The best way to deal with asbestos in this case depends on the equipment's condition. Asbestos that is friable will crumble easily and fall apart, releasing fibers in the air. Because asbestos was used for insulation or repairs of boilers and water heaters, it is likely that it has broken down over time. The equipment itself may not be the problem, but removing it for replacement with a new model can stir up dust and debris. In this case, homeowners should hire an asbestos remediation professional to eradicate the asbestos before installing new equipment.
Asbestos Cement Pipes
As with other building materials, asbestos was frequently added to cement to make it harder and more durable. Builders often used asbestos in cement to build plumbing lines connecting a house to the municipal water or sewer lines. As such, these pipes can be buried many feet underground, making them quite difficult to access. Although asbestos tends to cause the most harm when it is airborne, it can also contaminate the water supply.
Cement and concrete break down over time. Asbestos cement pipes can, after years of use and minor breakage, release the fibers into the water supply. However, very small quantities of asbestos may not pose a lot of risk. Removing the pipes would likely create as many problems as it solves. Cities and counties may take responsibility in testing the water for signs of contaminants like lead or asbestos, particularly those from older pipes. If the levels rise beyond a certain agreed limit, city officials may alert homeowners in the area. When asbestos cement pipes start to disintegrate, they need to be replaced by a qualified professional and may require assistance from the city.
Garages are one of the most likely places people will find asbestos. Anything built in the 1980s or earlier probably has it in some building material. Garages tend to contain more cement than the rest of the house, which means that a garage might be a bigger risk to homeowners than the home or other buildings on the property.
For the most part, garages have asbestos in cement roofing tiles or cement siding. Otherwise, asbestos can be anywhere in the garage that might also have been put in the house, such as:
- Roofing, fascia, and cladding
The best way to manage asbestos in the garage depends on its source. Many home-built garages feature cement walls that may contain asbestos. In this case, it might be better to demolish the old garage and build a new one than to try to repair a few blocks or panels that are cracked or breaking down. Otherwise, if the garage is in good condition, homeowners may not have to do anything at all. Instead, they might prefer to look for less-costly methods of containing the asbestos, such as encapsulation.
Protecting Your Home from Asbestos Exposure
Asbestos seems like a great addition to many building products, if not for the harm it can cause. Managing asbestos in the home calls for a balance of watch and wait and active remediation. In most cases, homeowners may be able to keep the asbestos without putting themselves at risk, as long as it remains in ideal condition. Once it is no longer at that state, prompt action to remediate it with a professional trained to do so safely is the best choice. If there is concern about a specific building material being ACM, an asbestos testing laboratory should determine its contents. By paying attention to the likely causes, people can determine how best to approach asbestos in their homes as they find it.
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