Asbestos hazard in flooring or roofing adhesives, mastics, or sealants:

This article provides opinion & comment on the hazard of friable asbestos release from flooring or roofing adhesives, mastics, or sealants.

This article series answers questions about floor tile, sheet flooring, or roofing cutback adhesives or mastics that may contain asbestos.

Does or did roofing mastic products & sealants contain asbestos?

What are the hazards of demolishing or working on floors or roofs where asphalt-based asbestos-containing mastics, cutback adhesives, or sealants were used? Page top photo of black mastic floor tile adhesive provided courtesy of reader G.M.

Does Flooring Mastic, Cutback adhesive or Roofing Sealant/Mastic Contain Dangerous Levels of Asbestos?

In our roof sealant photograph (left) we are inspecting a roof that was patched in the 1980's - it would be reasonable to treat this roof flashing cement or patching compund as Presumed Asbestos Containing Material (PACM).

Certainly as we see in Rosato [23], the asbestos industry was constantly looking for uses of asbestos mining waste products that included granular asbestos dust and short asbestos fibers.

Asbestos fibers were used as a strengthening material in roof flashing cements as well as in flooring mastics and cutback adhesives.

Asbestos was used in those forms in vinyl-asbestos flooring in both floor tile and sheet flooring forms.

And as we document at CERAMIC TILE, ASBESTOS / LEAD?, asbestos was used in mixture with ceramic fibers (for certain products such as filters) and in ancient pottery applications.

Our photo (left) illustrates a floor tile installation in Barcelona, Spain. These floor tiles are estimated at more than 50 years old.

At ASBESTOS IDENTIFICATION IN BUILDINGS - we point out that the EPA and other expert sources note that

... not all asbestos-containing products are dangerous. A health risk exists only when asbestos fibers are released from a product [into the air where they are inhaled for example].

Products that are friable (easily crumbled or made into dust that is easily airborne) are more dangerous than products in which binders immobilize the asbestos fibers.

EPA also indicates that not everyone exposed to asbestos will develop an asbestos-related illness or disease. Most people exposed to small amounts of asbestos do not develop asbestos-related health problems. Cigarette smokers are at much higher risk of asbestos-related disease. [1][2][3][4][5]

It is usually reasonable to cover over an asbestos-suspect floor, thereby significantly reducing the risk of sending asbestos fragments or particles of flooring or floor adhesive into the air at detectable levels. And by leaving the flooring material in place you actually expose the building to less asbestos hazard risk than by removing it (in most cases).

Watch out: demolition projects that disturb any asbestos containing material may produce friable asbestos debris, dust and thus airborne particles at dangerous levels, particularly if EPA or other expert advice is not followed.

For example, see ASBESTOS REMOVAL, WETTING GUIDELINES.

Floor Tile Mastic Adhesive Asbestos Content Report

Reader Comment: floor tile mastic adhesive asbestos test results

12x12 “vinyl” tiles. ~3/32 thick, Travertine tile pattern - photo shown here.

House built in the U.S. in Ohio in 1971.

The floor was glued down with a dark/black adhesive.

Floor surface is beige (or dirty) brown spots are recessed.

Nothing printed on back of tile… ( does printing fade over time?)

Tile is fairly brittle. this loose tile is in one piece, but cracked in two places.

Your website is extremely helpful and important. if I’d not found it, would have followed the common advice we were getting of …

“they stopped making that [asbestos-containing floor tiles] in the 60’s” and “that was only the 9x9 tiles”. - Anonymous by private email 2018/05/22 [details on file]

[The back of one of the reader's floor tiles showing the notched-trowel spread pattern of tile mastic is shown below - editor.]

Reply: asbestos-containing tile mastic & floor tiles produced in all sizes up to early 1980's

In fact asbestos-containing floor tiles were made in a remarkably wide range of sizes, even "custom-cut" sizes, die cuts, etc.

We've reviewed flooring catalogs documenting regular cut floor vinyl asbestos "tiles" from 3" to 36" square as well as in strips and other forms.

I've spent a lot of time around construction as well as some other fields in which experts give a vehement opinion as if God told them, yet the speaker has not even read the instructions on the box.

Fortunately Vinyl-Asbestos floor tile in good condition is not friable and does not deserve to be treated in an expensive panic.

Reader follow-up: real estate agent misleading comments on asbestos floor materials

I plan to send off pieces of the one tile we collected and get I tested.

I will send you results once we do that.

And I will inform the real estate agent your advice PAMC and if further inform it comes back positive so they will have to disclose it.

And then, I will go back onto the links and post comments when I have more complete information, because this is very important and people are being misled by real-estate professional who should be better educated on the subject!

Reader follow-up: tile mastic 5% asbestos, floor tile 2% asbestos

We got the report back from our asbestos test on the floor tile and tile mastic shown here.

The tile was found to contain 2% asbestos and the black mastic on the underside of the floor tile was found to contain 5% asbestos. - Anonymous by private email 2018/06/26 [details on file]

Thank you!

Reply: managing the risk of airborne asbestos-laden dust during old floor tile mastic removal

Thank you, Anon, for the photos and tile mastic asbestos test report that we have discussed by email. I include that here to assist other readers.

Asbestos is safe and legal to remain in homes or public buildings as long as the asbestos materials are in good condition and the asbestos can not be released into the air.

Tile mastic adhesive is not normally friable nor even exposed when a vinyl-asbestos tile floor is installed and intact.

However there could be a bit of airborne asbestos-containing dust if the floor is demolished using mechanical means. Using wetting or solvent procedures to remove tile mastic, if that's actually necessary, can minimize that hazard.

In removing old vinyl or asphalt based floor tiles we have found that some mastics are water soluble - it's always best to try using the least- aggressive, least-chemically-dangerous solvent first when cleaning or removing building materials.

Other mastics might be soluble using odorless paint thinner.

Sanding to remove floor tile mastic that remains during remodeling, for example in an effort to restore an old wood floor that was tiled-over, risks more-dangerous levels of airborne asbestos-containing dust. In that case appropriate work area containment, dust control, protective clothing and respirators, and post-sanding cleanup are almost certainly going to be needed.

For more photos of tile adhesives and mastics, some of which contain asbestos,

see ASBESTOS MASTIC IDENTIFICATION

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2021-02-23 - by (mod) -

@dd, what you described sounds quite reasonable to me.

On 2021-02-23 by dd

Had our old tile and mastic tested, each came back 2% chrysotile asbestos, non-friable. Was advised to wet down any that had to be removed (along baseboards when removing carpet, for example) but then float the new floor on top. Did that in a couple of rooms a decade ago. Fast-forward to water damage in kitchen last week and a dozen or so tiles came loose. I put on my mask and gloves, wet down the floor and carefully removed the tile. Never saw any dust, even when some pieces broke. I double-bagged the trash and will dipose of properly. Wet down the floor again and let it dry overnight. Put down peel-and-stick tile today. Eventually will float new flooring over entire room. In my experience, not as scary as I thought it would be, because I never filed or sanded anything, so no dust was created.

On 2021-02-12 by (mod) - Chrysotile asbestos confirmed in tile mastic adhesive

thanks Ben; that may be an asbestos-containing asphalt-based mastic adhesive.

On 2021-02-11 by Ben - 5-10% Chrysotile 95% Matrix

I tested a number of plaster over wallboard panels in my house and none were found to contain asbestos.

However, we did find a small amount in this tile adhesive layer.

Tan Homogeneous 5-10% Chrysotile 95% Matrix

This Q&A were posted originally

at ASBESTOS in PLASTER

On 2020-12-01 - by (mod) -

No dust would mean low risk, but to ease your worry you can damp wioe and HEPA vacuum the area.

On 2020-12-01 by Genesis

Hi. I am very very not peaceful right now as my husband was trying to fix our bathroom he had that black underlayment which been exposed for days as we used the bathroom back and forth. So after putting vinyl floors. I found out online that it is possible asbestos mastic what we have.

And I qm totally alarm coz we have 2 kids. And I remembered he mop it so it became very sticky before he put the floor. What should we do?

On 2020-11-06 - by (mod) -

Pam

Asphalt-based mastics that contained asbestos are not highly friable - not easy to make into an airborne asbestos hazard; however during old floor demolition and scraping and cleanup, even vacuuming unless you're using a HEPA-rated vacuum, can generate some particles small enough to become airborne asbestos dust hazards.

So you'd follow the recommended wetting and dust control and cleanup procedures in the references cited in these articles.

On 2020-11-06 by Pam

What is the danger of removing black asbestos mastic we've found between two layers of tile and cement slab. We are renovating and parts of the floor need to be dug up for plumbing, so the mastic must be removed.

On 2020-09-09 - by (mod) -

Nancy

"Safe" isn't something one can promise based on e-text about a building condition; but frankly I doubt that it's reasonable to even try to do more mastic removal. Instead I'd go ahead and sand the flooring, but take care to use appropriate personal protection (masks etc), and dust control, followed by thorough cleanup.

On 2020-09-08 by Nancy

I've removed the black mastic from my hardwood floor by using a wet method and scraping. I rubbed the floor after scraping with mineral spirits to remove the last traces of mastic. The floor boards are stained black (I think from the mastic) and I think there must still be some residual mastic left in the cracks between the boards although the floor is not sticky at all. Is it safe to sand the floor now, or will the top millimetre or so of wood still have asbestos fibers in it?

On 2020-07-13 - by (mod) -

There may be some dust to be cleaned up by damp wiping and HEPA vacuuming. The dust may be from broken tile fragments or penetrations of tack strip nailing. The tile itself is not friable..

On 2020-07-13 by Maryla

Having old carpet replaced and found 9x9 tile underneath carpet. Professionally tested and report came back vinyl tile had less than 1% asbestos (no danger) but the black mastic contains 5-10% asbestos. Tack strips must be removed but some of the tile under the tack strip is cracked and broken. Tiles will be encased in self-leveling compound but strips must be removed. Is the tile underneath the tack strips now in a friable state and is it safe to continue removing tack strips?

On 2015-01-04 by (mod) -

Judi please see ASBESTOS FLOORING HAZARD LEVEL ASSESSMENT

On 2015-01-04 by judi cellini

Wondering about ther danger of old asbestos tiles and mastic in 2 basement rooms.

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Continue reading  at ASBESTOS-MASTIC REMEDIATION or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• ASBESTOS FLOOR TILE COMPOSITION
• ASBESTOS FLOORING HAZARD REDUCTION
• ASBESTOS FLOORING LEFT IN PLACE
• DOES THIS FLOOR CONTAIN ASBESTOS? - 5 easy questions to tell if your FLOOR probably contains asbestos -
• DOES THIS MATERIAL CONTAIN ASBESTOS? - 5 easy questions to tell if a BUILDING MATERIAL probably contains asbestos -
• MASTIC, CUTBACK ADHESIVE, FLASHING CEMENT ASBESTOS
  • ASBESTOS-CONTAINING ADHESIVES
  • ASBESTOS-CONTAINING MASTIC DANGEROUS?
  • ASBESTOS MASTIC IDENTIFICATION
  • ASBESTOS-MASTIC REMEDIATION
  • ASBESTOS SOURCES in MASTIC or UNDERLAYMENT
  • ASBESTOS MASTIC INTO AIR?
  • FLOORING ADHESIVE MASTIC SEALANTS
  • ROOF SEALANTS & MASTICS

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ASBESTOS-CONTAINING MASTIC DANGEROUS? at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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