Does Your Roof Contain Asbestos? What Pacific Northwest Homeowners Need to Know

For homeowners across Washington, Oregon, and the greater Pacific Northwest, this is not a distant concern. It's a real possibility hiding right above your head.

This post will walk you through what asbestos is, why it ended up in roofing products, how to spot signs of potential risk, and what you should do next. We'll keep it simple and practical because this information could protect your family's health.

What Is Asbestos and Why Was It Used in Roofing?

Asbestos is a natural mineral that was once considered a miracle material. It's fire-resistant, durable, and very cheap to work with. Starting in the 1920s, asbestos was mixed into hundreds of building products — including roofing materials.

Manufacturers added asbestos to roofing products for very specific reasons:

• It resists fire. Roofs are exposed to the sun, embers, and heat. Asbestos helped reduce fire risk.
• It's strong. Asbestos fibers added strength to shingles and other roofing materials without adding much weight.
• It handles moisture well. The Pacific Northwest gets a lot of rain. Asbestos helped roofing materials hold up under constant wet conditions.
• It lasts a long time. Asbestos-containing roofing products were marketed as long-lasting, low-maintenance solutions.

It seemed like a perfect solution — until researchers discovered that inhaling asbestos fibers causes serious, often fatal lung diseases including mesothelioma, asbestosis, and lung cancer. By the late 1970s, the U.S. Environmental Protection Agency (EPA) began restricting its use. However, asbestos was never fully banned in roofing products in the United States, which means some products containing asbestos may still legally exist today, and millions of older roofs still contain it.

What Roofing Products Commonly Contained Asbestos?

1. Asbestos Cement Shingles: These flat or corrugated shingles were extremely popular from the 1930s through the 1970s. They look similar to today's fiber cement products but contain asbestos fibers mixed into the cement. They were widely used on homes, garages, and sheds throughout the Pacific Northwest.
2. Built-Up Roofing (BUR) Felt: Many flat and low-slope roofs used layers of tar paper and asphalt. The felt layers in these systems often contained asbestos fibers. If your home, garage, or commercial building has a flat or low-slope roof that's decades old, asbestos in the underlayment is a real possibility.
3. Roofing Felt and Underlayment: Even if the shingles themselves didn't contain asbestos, the felt paper underneath them often did. This is especially true for homes built before 1980. When the top layer of roofing is removed during re-roofing, the underlayment below can release asbestos fibers into the air.
4. Asphalt Shingles: Some asphalt shingles manufactured before the mid-1980s contained asbestos as a reinforcing fiber. They look like standard asphalt shingles but can't be identified by appearance alone. Testing is the only way to know for sure.
5. Roof Coatings and Mastics: Sealants, adhesives, and coatings applied to roofs sometimes contained asbestos. These products were used to patch leaks or coat flat roofs and can still be found on many older structures today.

Why the Pacific Northwest Is a High-Risk Area

The Pacific Northwest has a unique combination of factors that make asbestos in roofing a bigger concern here than in some other parts of the country.

Older housing stock. Cities like Seattle, Portland, Tacoma, Spokane, and Bellingham have large numbers of homes built between 1940 and 1980 — right in the prime asbestos era. Many of these homes have never had their roofing materials tested.

Heavy rainfall and roof wear. The Pacific Northwest averages some of the highest rainfall in the continental United States. Constant moisture breaks down roofing materials over time. As asbestos-containing products age and deteriorate, they can release fibers into the air. This process is called "friability" — when materials become brittle and crumble, they become more dangerous.

Active re-roofing market. Wet climates mean roofs wear out faster. Homeowners in this region replace roofs more frequently than those in drier climates. If your contractor removes an old asbestos-containing roof without proper precautions, you and your neighbors could be exposed to airborne asbestos fibers.

DIY culture. Many Pacific Northwest homeowners are do-it-yourself minded. While that's admirable, disturbing asbestos-containing roofing materials without proper training and equipment is extremely dangerous and illegal in most circumstances.

How Do You Know If Your Roof Has Asbestos?

Here's the hard truth: you cannot tell by looking. Asbestos fibers are microscopic. Asbestos cement shingles look similar to modern fiber cement products. Asbestos-containing felt looks like standard roofing felt. Even experienced contractors cannot identify asbestos visually.

The only way to know for sure is to have the materials tested by an accredited laboratory.

What Happens If Asbestos Is Disturbed?

When asbestos-containing materials are broken, cut, sanded, or removed without proper controls, microscopic fibers become airborne. These fibers are invisible to the naked eye. You can't smell them or taste them. But if inhaled, they can lodge permanently in lung tissue.

The diseases caused by asbestos exposure — mesothelioma, lung cancer, and asbestosis — typically don't show up until 20 to 50 years after exposure. By the time symptoms appear, the diseases are often advanced and very difficult to treat.

This is not meant to frighten you unnecessarily. Asbestos in good condition that is left undisturbed is generally not an immediate hazard. The risk comes when materials are damaged, aging, or disturbed during repair or renovation.

What Should You Do Next?

If you have any reason to believe your roof may contain asbestos, here are the right steps:

Don't disturb it. Don't attempt to remove, sand, drill, or cut any suspected asbestos-containing roofing materials.

Call a licensed asbestos inspector. A certified inspector or abatement contractor like Absolute Asbestos Services will collect samples safely and send them to an accredited lab for testing. This is the only way to know what you're dealing with.

Get a professional assessment. If asbestos is found, an abatement professional will assess the condition of the materials and recommend either encapsulation (sealing) or full removal.

Use a licensed asbestos abatement contractor. In Washington asbestos removal must be performed by licensed contractors following strict state and federal regulations. This protects your family, your neighbors, and the workers on the job.

Ensure proper disposal. Asbestos-containing materials are classified as hazardous waste. They must be disposed of at approved facilities — not in your regular trash or at standard landfills.

Absolute Asbestos Services Is Here to Help

At Absolute Asbestos Services, we specialize in helping Pacific Northwest homeowners navigate the asbestos process from start to finish — testing, inspection, abatement, and disposal. Our team is fully licensed, trained, and equipped to handle asbestos safely and in full compliance with Washington State Department of Labor & Industries regulations and EPA guidelines.

If you're planning a roofing project or just want peace of mind about your home, contact us today for a consultation. (425) 923-6994