FAQs: Asbestos Content in Plaster

Q&A on asbestos in older plaster walls & ceilings

Photos of Plaster that May Contain Asbestos

Does this look like plaster that would contain Asbestos?

Our InspectApedia reader asked:

I have an old house that was my grandparents. It was originally build in 1900, but they added a lot to it and had the whole house plastered in either the late 1950s or early 1960s from what I gather. After looking around this site, it looks like a 2 layer system on metal lath.

Last year a section of the bathroom ceiling came crashing down. It looks like it was where an old leak caused the top layer, assuming skim coat, and several layers of paint to hang free from the rest of the plaster. Then, with the help of water from steamy showers, a three foot or so section came crashing down.

Now, the thicker bottom layer of plaster looks like it is drying out. I’m not sure if it’s because it’s getting wet or drying or the cycle, but it’s dropping little white looking crumbs on the floor below throughout the day every day.

To me this bottom layer looks more white and less chunky than a lot of the brown layers I see on here. There aren’t black specks or anything that I usually see here either.

My concern is with asbestos. I plan to get it tested, but I’m not sure if there are recommended testing companies or the best way to do this. Does this look like a general type of plaster that would have asbestos?

The house does’t have central air, so fans are always going all over the house. If it helps, the house is in southern Indiana, near Louisville, Kentucky. - Kyle Wilkins, 2025/06/11 - posted originally at ASBESTOS in PLASTER FAQs 

Recommendations by InspectApedia Publisher (mod)

@Kyle Wilkins,

Here's what we saw in your second photo:

@Kyle Wilkins,

The answer to the asbestos in plaster question turns in part on the age and location of the building, but in any event, plaster dust itself is not healthy to breathe.

Please also take a look at our detailed advice found in this article:

HOW TO REPAIR SMALL DAMAGE in ASBESTOS-SUSPECT DRYWALL or PLASTER
where we've moved this discussion and added some detail as well as including your other photo.

I'll appreciate your further comments, questions, suggestions.

Daniel

Question: is the material shown in this plumbing access photo asbestos?

We are getting ready to rent (have put down a deposit) on a house built in 1955.

There is this easily accessible panel on the wall opposite the bathroom for access to the plumbing for the tub. Is or could this be asbestos? We have a 2 year old daughter and don't want to take any chances! 2018/05/15 shelby.hudson655321

Reply:

Shelby

Your photo shows cement or plaster extruding through expanded metal lath, no doubt providing the wall onto which bathroom tile was affixed.

While some plaster in older homes might (rarely) contain asbestos, this is not a friable material.

Even if the plaster contains asbestos you would have to grind, saw, or chop the material to create dust and thus to create a measurable hazard.

In sum, undisturbed, this plaster in the plumbing access is not a child hazard.

See details about this wall construction and its materials

at PLASTER LATH, METAL

Might this pebbled ceiling surface contain asbestos?

Is it possible that this may contain asbestos. - see ceiling photo above. On 2019-07-12 by CECI

Answer by (mod) - Yes but don't confuse asbestos in popcorn ceiling paint with asbestos in plaster

Yes but notice that here we're looking at textured or popcorn ceiling paint that may contain asbestos - regardless of whether this paint was applied to drywall, gypsum board, or plaster surfaces.

Details are at CEILING PAINT TEXTURED / POPCORN ASBESTOS 

Asbestos Contamination From Demolition or Remodeling FAQs

What's the level of asbestos hazard from drilling a hole into expanded metal lath backed plaster?

Hi, here is a picture of a plaster wall with metal lath behind ( that I drilled through in order to pass cables through for a wall mounted TV). The picture is a close-up of the hole, it is about 1 inch in height.

The metal lath is not visible in the pic, and at this point In too afraid to disturb it further.

After reading around I'm concerned that the plaster has asbestos content.

I live in an old concrete building in Hamilton, Ontario but I am not sure when it was built, my best guess 1970s or 80s.

Do you think I should be worried? I am thinking of bringing someone in to get the material tested. - On 2020-03-09 by Tomor Sodnompil

by (mod) - Possible asbestos in plaster on expanded metal lath in Hamilton, Ontario, Canada

Tomor

It is possible that your ceiling plaster contains asbestos.

For such limited damage of single hole drilled to pass some cables and assuming that it's otherwise in good condition, it's reasonable that you would clean up the dust and you could stop there.

Use damp wiping and HEPA vacuuming to clean up the dust.

What do I do if I disturbed asbestos-suspect plaster in my 1954 Baltimore Home? Is my House Contaminated?

I live in a house near Baltimore built in 1954. I did a lot of work on the house about 8 years ago during which I removed some plaster-over-rocklath walls. Recently I've become aware that plaster and/or rocklath often contained asbestos, which makes me feel absolutely sick.

I've just taken a sample of the wall to send out for testing (I'll post results when I get them), my question is: what do I do if it's positive?\

I remember trying to avoid creating dust by minimizing sawing when removing the plaster, but I'm sure I just shop-vac'd up any dust I did create.

How long might my house have had unsafe levels of airborne asbestos (or could it still be contaminated)? On 2023-02-28 by Mark

Guidance by InspectApedia Editor - damp wipe and HEPA vac all surfaces or get dust sample tested

@Mark,

We're flying blind here as we can't see and know so little about your home, but if there is dust remaining from your work done 8 years ago, or if you're worried that there may be such harmful dust, you'd damp wipe and HEPA vac all surfaces, from the work area on outwards to include nearby rooms that might have gotten some of that dust.

OR you could collect some representative settled dust samples such as from trim over a window or door - surfaces probably not cleaned recently, to see if an environmental test lab finds notable levels of asbestos in the dust.

And keep calm; the anxiety about asbestos is bad for your health and worse if it turns out there was no asbestos in the first place.

by Mark

@InspectApedia Editor ,
Thanks for your reply. Just got the test results: negative!

by InspectApedia Editor

@Mark,

Thanks for taking the time to send us your update.

What do I do if I disturbed asbestos-suspect plaster in my 1954 Baltimore Home? Is my House Contaminated?

I live in a house near Baltimore built in 1954. I did a lot of work on the house about 8 years ago during which I removed some plaster-over-rocklath walls. Recently I've become aware that plaster and/or rocklath often contained asbestos, which makes me feel absolutely sick.

I've just taken a sample of the wall to send out for testing (I'll post results when I get them), my question is: what do I do if it's positive?\

I remember trying to avoid creating dust by minimizing sawing when removing the plaster, but I'm sure I just shop-vac'd up any dust I did create.

How long might my house have had unsafe levels of airborne asbestos (or could it still be contaminated)? On 2023-02-28 by Mark

Guidance by InspectApedia Editor - damp wipe and HEPA vac all surfaces or get dust sample tested

@Mark,

We're flying blind here as we can't see and know so little about your home, but if there is dust remaining from your work done 8 years ago, or if you're worried that there may be such harmful dust, you'd damp wipe and HEPA vac all surfaces, from the work area on outwards to include nearby rooms that might have gotten some of that dust.

OR you could collect some representative settled dust samples such as from trim over a window or door - surfaces probably not cleaned recently, to see if an environmental test lab finds notable levels of asbestos in the dust.

And keep calm; the anxiety about asbestos is bad for your health and worse if it turns out there was no asbestos in the first place.

by Mark

@InspectApedia Editor ,
Thanks for your reply. Just got the test results: negative!

by InspectApedia Editor

@Mark,

Thanks for taking the time to send us your update.

Is this 1950s wall material asbestos in my Maine Home? Worried about asbestos getting on my clothes.

What wall material is this? It's part of my closet. Apartment in a house that was built in 1900, renovation listed in 1950, in Maine. My clothes have been rubbing on it for a few years. The exposed part looks like crumbly concrete. Hoping its not asbestos.

On 2022-09-22 by Kristy

by InspectApedia (Editor)

@Kristy,

That looks like plaster or plasterboard perhaps with a layer of wallpaper and more layers of paint.

Very tiny area of damage - easily repaired by removing loose paint and coating with joint compound or plaster patch compound.

by Kristy

@InspectApedia (Editor), If it has asbestos, should I be concerned about my clothes being contaminated?

I threw out a couple shirts that had white on them just in case. I recently thought of the possibility of asbestos in it. Would the risk have be high?

by InspectApedia-911 (mod)

@Kristy,

One can't assess an asbestos hazard by text but I read nothing in your post that would have led me to toss clothing away.

Worried about asbestos from clothes hangers craping my plaster walls

@InspectApedia-911, I was worried since my hangers have been scraping against the exposed part and getting on my clothes for three years. I'm not too sure how friable asbestos plaster is and how big the risk is. Never thought twice about the possibility until now.

I guess I'm looking for a theoretical answer? I truly appreciate your help. This has been a very insightful website! On 2022-09-23 by Kristy

by InspectApedia-911 (mod)

@Kristy,

Friable means that a material can easily be made into a very fine powder that would be airborne simply by rubbing the material between your forefinger and thumb.

Cementious materials including plaster are not friable.

Furthermore as I've said several times now the total quantity of material exposed by a 1 inch small gouge or crack and plaster is simply insignificant.

Finally you have no reason to know that your plaster actually contained any asbestos.

Which HEPA Vacuum Cleaner is Best for Cleaning up Asbestos-Suspect Plaster Dust?

I have seen you recommend HEPA-vacuuming when cleaning up dust, rather than using an ordinary shop vac. Is a HEPA vacuum a specific model, or can I use my ordinary shop vac with the HEPA filter installed?

Thanks in advance for your help, and for your hard work on this site! On 2022-09-10 by Michael

Answer by InspectApedia-911 (mod)

@Michael,

That's a GREAT question, thank you.

I've been guilty of ducking the really hard question about HEPA vacuums.

A long way back my friend Jeff May (Cambridge MA) tested a bunch of HEPA-rated vacuum cleaners to see just how well they really worked to remove fine particles.

What Jeff found was just what we both had thought: MANY HEPA-rated vacuum cleaners of various designs were so leaky that they actually increased the level of airborne particles while running, even though they also were vacuuming up and keeping some dust and debris.

At the time Jeff found that the most expensive Miele vacuum was among the least leaky - and was NOT an industrial nor shop-vac grade in vacuuming capacity.

But that was decades ago.

I suspect that today we'd find the same range of performance.

So lacking an independent, trusted testing lab report on HEPA Vacuum effectiveness and leakiness, I'd look for a model that's rated as not leaky.

I suspect (but don't know for fact) that ANY normal shop vac that's retrofitted with a HEPA filter inside the vacuum cleaner is rather leaky.

A web search for "HEPA RATED VACUUM CLEANER REVIEWS" yields a blizzard of articles on "best HEPA vacuum" but

Watch out: I would read those reviews with great care to see just what the reviewers considered important, what tests were performed, and with what expertise.

Then take a look at

ASTM F3150-18 - Standard Specification for HEPA Filtration System Performance of Residential and Commercial Vacuum Cleaners

1. Scope

1.1 This specification defines industry acceptable test methods and approaches for evaluating residential and commercial vacuum cleaner filtration systems to HEPA filtration performance levels.

1.2 This specification defines the minimum filtration efficiency requirements for achieving HEPA performance for filtration systems of residential and commercial vacuum cleaners.

1.3 This specification applies only to residential and commercial vacuum cleaning products that are used in non-critical applications. Non-critical applications refers to applications not requiring the removal of hazardous dust as defined per IEC 60335-2-69.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

available from ASTM

Asbestos in Pre-1920s Plaster FAQs

Photos of old plaster in a 1908 home - this may contain asbestos?

So do you think we are at risk of exposure to asbestos or crystalline silica?

I’m so ready to be out of this old House. On 2018-03-21 by Vickie -

Simple cleanup tips by (mod) -

I would damp wipe, then HEPA VAC for cleanup.

Be sure to use the proper HEPA vacuum cleaner (one that doesn't leak) in order to avoid making asbestos-containing dust even more airborne and more dangerous. Some experts, fearing such aeration, recommend simply damp wiping surfaces.

Followup by Vickie: the plaster is shedding

This is a 1908 house. Upon further inspection plaster and a sand like substance are falling off around the furnace and in the air handler area.

Now I am terrified my family has been breathing in asbestos and silica for years unknowingly because of a failing plaster job.

Can I HEPA vac this stuff up or wet mop? Advice is greatly appreciated.

This is a circa 1908 house. After further inspection, I have found that plaster has fallen out in the area/box surrounding/encasing the air return.

There are chunks of it falling and a sand like substance on the floor. Now I’m in panic mode worrying that our entire house has been sprayed with asbestos and silica.

What should I do? I have a true HEPA vac that I bought for another issue. Is it safe to suck up this debris or should I wet mop. Thanks for any help because I am terrified.

by Vickie - some older pre- 1920s plaster contained asbestos

I’ve read that some plaster did have asbestos added, & I’m hoping with our 1908 house this has none. I was concerned that my air return was sucking in this dust and contaminating us, especially given the crystalline silica push now.

I used a NIOSH filter mask and wet wiped things, even spraying some with soapy water before using a HEPA vac to remove the plaster chunks and sand.

The plaster is just crumbling into sand. I pray it isn’t asbestos. I have 2 young boys that I worry a lot about.

by (mod) -

It would be foolish of me to pretend that I could inspect her assess the environmental dangers in your home by a brief a text in a few photographs.

Please remember what I sent you previously.

Just picking up a few chunks of plaster to drop into the trash is not likely to contaminate you, your house, your family - nor would it alone create a measurable airborne asbestos hazard even if the material contained asbestos.

As you probably know plaster dust is alkaline and respiratory irritant. But a fundamental concept with any exposure is that the dose makes the poison.

by Vickie: concerned about asbestos drawn into the heating or air conditioning air handler and ductwork

I’ve read that some plaster did have asbestos added, & I’m hoping with our 1908 house this has none.

I was concerned that my air return was sucking in this dust and contaminating us, especially given the crystalline silica push now.

by Mod - Also inspect the HVAC air handler & ducts for plaster dust contamination

We agree. It'd be easy to inspect your air handler.

In any event if the air handler or ductwork are dust-contaminated it'd make sense to have them cleaned.

Yes plaster was used in some asbestos mixes as we discuss in detail

at ASBESTOS in PLASTER

To be accurate, plaster is not asbestos.

Some plaster mixes contained asbestos however.

Worried about asbestos in the Claremont Hotel Built in 1915

I'm working at The Claremont Hotel I'm curious if the plaster has asbestos in it but I have a sore throat On 2022-03-27 by Jerry power

Reply by InspectApedia Com Moderator - Claremont in Berkeley - undamaged plaster walls, with or without asbestos, do not pose risk

@Jerry power,

Please take a look at ASBESTOS in PLASTER where we discuss the answer to your question.

Of course we won't have any specific information about the plaster in the Claremont, but if you're describing the Claremont in Berkeley, it was built in 1915 - old enough that a variety of plaster formulas may have been used over its lifetime.

Just walking by or working around plaster walls and ceilings that are undamaged and intact has a zero chance of causing an asbestos-related illness or even a plaster-related illness.

It's not likely that asbestos dust caused your sore-throat.

More likely is a recent exposure to COVID or to a guest carrying a respiratory illness, OR if you've been doing demolition of plaster walls, plaster dust itself is highly irritating.

Question: Is there asbestos in expanded metal lath plaster in our 1847 home?

We just found a ceiling in our 1847 house which is unlike the other plaster-and-lath ceilings; it is an expanded metal lath, hard cement or concrete, on wood lath.

Photo below. I do not see anything fibrous that would indicate that it contains significant amounts of asbestos. Any opinions?

I would like to open some holes for ducts (using standard mask etc. protection). Thanks in advance! 2019/12/21 D.Shoemaker

Reply:

Expanded metal lath and plaster will be a newer material than older wood-lath.

You would not be able to literally "see" asbestos in cement or plaster even if it is present as the individual fibers are too small. Asbestos in your plaster would be unusual but not impossible; you'd either treat the material as presumed to contain asbestos (dust control, etc) or have a sample tested.

Certainly because silica dust is also hazardous to breathe or to get into your eyes, you will want to use basic dust control measures and appropriate protective gear when cutting, drilling, or demolishing any plaster walls or ceilings.

To be extra careful

see ASBESTOS REMOVAL, WETTING GUIDE

Watch out: even if the plaster does not contain asbestos, the silica dust that is created during sawing or grinding or demolition is a respirator hazard, particularly at higher levels.

Watch out: also, that metal lath will give a nasty cut if you don't wear heavy gloves when handling it.

Reader follow-up: fibers visible in plaster

Thanks. I include a ~30x photo which shows one visible fiber. We will send off the sample for testing, but any further observations welcome. I'll report back what I learn.

Moderator reply:

DS that fiber looks like a fragment of broom straw or wood or a wooden twig; you would not see asbestos in a thick twig-like particle like that. That won't be asbestos.

Some of our photos of asbestos are at ASBESTOS UNDER the MICROSCOPE

Reader follow-up: this plaster did not contain asbestos

2020/01/13 David Shoemaker

I'm happy to report there was no asbestos found in the sample. thanks again for the exchange --

Asbestos in 1920's - 1930s Buildings FAQs

What should I do about asbestos in the Popcorn Ceiling in our 1925 California Home?

We just moved in to A 1925 home in California. Half the house is an extension they did in 2010.

We have popcorn ceiling in one room ( not the updated part of the house (2 layered vinyl tile we removed, covered the popcorn in the laundry room with drywall now that I’m finding out about asbestos.

I’m freaking out .

I wet the air in the kitchen , wiped everything out and have HEPA purifiers all around the house .

Should I be concerned. Also the thinking of putting drywall in one of the bedrooms in case it has it . When doing that .. would you say that’s considered
A limited cut. Should I do it . - On 2024-02-14 by What should I do

Suggestions by InspectApedia Publisher (mod)

@What should I do

For ceilings that you have already covered with new drywall, that was the correct solution and there won't be any continuing hazard from the asbestos that you covered as long as those ceilings are left alone and not demolished.

For popcorn painted ceilings that have not already been covered, doing the same thing as the least expensive and safest approach.

If you're concerned that you damaged or demolished a popcorn paint coated ceiling that may contain asbestos, now that the ceiling has been covered, all that remains would be to do some cleanup of any remaining dust by damp wiping at HEPA vacuuming.

Please clarify, if you are asking a different question.

Reader followup

@InspectApedia Publisher, my apologies let me clarify

Laundry room - a wall was knocked done due to water damaged and mold and popcorn ceiling was covered since it had a crack . A month before we moved in . Worker cleaned it with i hope was a HEPA vacuum seems like a lot of dust since they sanded the new drywall

Second thing

In the laundry and in the kitchen it had 2 layers of different vinyl flooring . The vinyl that was older and looked like the original flooring had black under it like matting . Clean and intact however, it was ripped off the floor so now I’m thinking that could have had asbestos as well .

So now all the flooring is out . I mopped and sprayed water and deodorant on everything and have had 3 HEPA air purifiers around the whole house to make sure . Am I doing enough
we have been living in the house now for 8 days now

Now we are going to put a bond that seals the floor then put new flooring in and paint the walls

Third thing
my husband wants to put TVs up and add new lights on the plaster that may or may not have asbestos.

Also what do you think of HEPA air purifiers .003 . Do they help . Is it enough

Fourth

And the other thing is in one of the bedrooms the only one with popcorn Ceiling now has 2 hair line cracks that we are going to get covered to make sure but my family is saying I’m over reacting to just leave it alone . I want to cover it too with drywall like the laundry room . But will we be having more exposure.

Appreciate your help. I am freaking out over here and can’t sleep. and I’m not comfortable in my own house. Thank you .

Advice by InspectApedia Publisher (mod)

@Anonymous,

Try not to freak out; the anxiety for a situation like this is in my OPINON often a greater health risk than the material that makes you worry.

Bottom line:

If you damp wipe, HEPA vac, and avoid any significant demolition of those old materials as you move ahead, there is no meaningful hazard remaining.

Drilling a small hole to mount a TV is fine. Just control and clean up the dust.

To minimize dust when I drill a hole in a wall or ceiling I put a couple of inches of wide blue painter's tape (masking tape) over the spot first.

A HEPA vacuum cleaner is helpful in that case.

EPA and other experts point out that even asbestos-containing drywall or popcorn ceiling paint are safe and legal as long as they're not being disturbed, damaged, demolished.

Thanks from Anon

@InspectApedia Publisher, thank you for your expertise. Very helpful

Asbestos in plaster in a 1927 home with coarse plaster walls?

My home was built in 1927 and has plaster walls. They are not ornate, just flat plaster.

I am attaching a photo of the edge of a cut made before we lived here to accommodate a vent. How likely is it that we have asbestos in the walls? On 2022-04-07 by MC

Advice by InspectApedia Com Moderator - more information and review of data is important

@MC,

It's a perfectly understandable question to ask what's the probability that my plaster walls contain asbestos.

I'm sorry to say we have no probability data that would permit any absolute answer. Guesses that are so speculative will probably be simply wrong.

The best I can suggest is to look through the information on the page above, reviewing the data that we have found by researching the asbestos-in- plaster question.

The bottom line is that if you avoid demolition or other activities that chop, grind, saw or sand or otherwise make a dusty mess of your plaster walls, it's not likely that there is a detectable asbestos hazard nor other dust coming from that source.

Possible asbestos in hair-reinforced plaster in a 1930 UK Building

Hi, I live in a house built late 1930's in the UK. The wall plaster has hair in it but my concern is if it contains asbestos

. Is there a percentage of how likely a house built around this time would contain asbestos? We have had a lot of building work done, by myself and builders on different occasions.

There was lots of dust as walls/ceilings were removed and can't recall the builders taking any precautions or being concerned.

I've sent a sample away to be test but can't seem to stop thinking about this. Thanks Kyle On 2021-08-31 by Kyle

Advice by inspectapedia.com.moderator

@Kyle,

Thanks, that's a great question, and one that I'm embarrassed to say, despite decades of work on this topic, I cannot answer:

I don't have any confidence in any number or percentage chance that 1930s plaster in the UK contained asbestos, though my gut feel is that it wasn't in most plasters.

Keep in mind that plaster dust is itself harmful on several scores: alkaline, and fine particulates;

But the worry may be the greater health hazard for you than the plaster, especially if you're not doing demolition or creating a dusty mess. If your plaster is intact it's not shedding particles at any meaningful level

I'd like to see photos (one per comment) of the front and wall cavity or attic side of our plaster walls or ceilings, and of course do share your lab result with us as that will help other U.K. readers.

by Kyle

@inspectapedia.com.moderator,
Thanks for getting back to me. Hopefully these pictures are decent, I've cut a hole in the wall (using a mask for most of it) to fit sliding doors. You can't really see lots of hair due to the way it's been cut but there are some in the pics. Thanks

by inspectapedia.com.moderator

@Kyle,

That's a great cross-section photo of classic plaster on wood lath. Thank you.

Yes, about the horsehair, the way we have most-often been able to see it in plaster, outside of forensic lab (where we can look by microscope) is in attics and stairwells where only the plaster rough coat was applied and then painted; often we could then see horsehair right on the plaster surface.

Once the top coat or skim coat of finish plaster is applied you'll only see it on the back plaster ears through the lath or in the lab or sometimes at where the plaster is broken rather than cut neatly.

by Kyle - test results: no asbestos found in UK plaster

@inspectapedia.com.moderator, Thanks again for your info on this. I'm pleased to say there was no asbestos found in the sample I had tested.

by inspectapedia.com.moderator - no asbestos found in this plaster on wood lath sample tested

@Kyle, good news, and thank you for taking time to follow-up; your photos and discussion and test results - no asbestos in this plaster - will help other readers.

Is there a Risk of asbestos in plaster on wood lath in a 1939 bathroom

Doing a bathroom renovation and wondering what you think is underneath this wall on the right.

It looks like plaster, affixed to a wooden lath, and then a metal mesh over that.

House was built in 1939, do you think this could contain asbestos? On 2021-02-24 by Jesse D.

Answer by (mod) - maybe; but control plaster dust properly regardless of asbestos

@Jesse D., I see plaster on expanded metal lath;

The asbestos question for plaster is discussed in better-detail on the page above than I should attempt to repeat here; please take a look and don't hesitate to ask if any of that is unclear or incomplete.

No one can say from a photo alone whether or not asbestos was used in plaster, but you should be sure to read what we know about that question, above.

Followup by Jesse D. - asbestos may be present in normal plaster, not fire-resistant nor decorative

Thanks. So, to be clear, since this plaster was in the bathroom, not decorative or fire resistant-needed, it’s not likely (though not entirely ruled out) to contain asbestos?

1940's Plaster Asbestos FAQs

Is there asbestos in the wall of my 1948 Los Angeles California. Home?

Hello. Just cut a wall for a return air duct and discovered my walls are plaster and rock lathe.

Looked into it and discovered many plaster walls contain asbestos. My house was built in 1948 in Los Angeles. From the looks of it and the building year, would you suspect asbestos? I will get it tested. Thanks you are a great resource.

On 2025-02-25 by John C

Answer by InspectApedia Publisher (mod)

@John C,

Unfortunately, since some plaster may contain asbestos it would make sense to treat any older plaster as if it contained asbestos and therefore to minimize dust contamination and to clean up carefully and of course to wear appropriate personal protective gear.

And unfortunately unlike drywall, it's hard to cut plaster for running duct work without creating some dust. If possible, I would try to make cuts using hand tools rather than a power saw.

The fact is that plaster dust is bad to breathe regardless of whether it contains asbestos.

So yes, use the appropriate dust control and clean up methods.

If you need more details see

DUST CONTROL METHODS WHEN CUTTING ASBESTOS CONTAINING DRYWALL OR PLASTER

Daniel

by John C

@InspectApedia Publisher,
Thanks for your timely response!

Asbestos in 1950's Plaster Ceilings & Walls FAQs

Should I seal cracks in the Asbestos-Suspect Plaster of my 1950's Ontario Home?

I renovated my house 1950’s house in southern Ontario. Removing baseboards adding new doors and casings etc. I did wear a p100 mask while removing the plaster some walls were removed but some plaster walls were left.

Wondering if I should add caulking at the bottom of all the baseboards and any gaps around electrical fixtures where particles could make there way into my airspace. The plaster did look friable behind the baseboards. On 2022-12-06 by Alex

Assessment by InspectApedia (Editor) - baseboard trim on plaster walls minimizes asbestos risk

@Alex,

If the bottom edges of your plaster walls are covered by baseboard trim there's no reasonable chance of a meaningful or even detectable asbestos hazard from that source.

You shouldn't need to caulk anything.

Was there asbestos in the bathroom wall I removed in a 1953 home?

I removed a bathtub and tile today from 1953 and I only wore a paint mask. I want to know if there were asbestos in it or not is there a way to tell? It was tile with a grayish brown plaster. On 2022-09-28 by Derrel

Answer by InspectApedia (mod)

@Derrel,

With just the few words of your message, we couldn't give a definitive or informed answer. You could try posting a photo to give us some added insight.

Where are you located - country, city?

Ceramic floor and wall tile produced in North America would not be expected to contain asbestos. However you may find asbestos in some tile grouts and thinset tile mastics. Read more at

ASBESTOS CONTENT IN CERAMIC FLOOR OR WALL TILE

Asbestos is possible but uncommon in ceramic tile.

Asbestos was common in tile mastics.

If any of your building products were made in the US before 1986 then there's some possibility that there was asbestos.

None of the comment nor the information that you have at hand would allow a useful speculation about the potential hazard level to which you have been exposed.

Let us know if you have additional questions.

by Derrel

@InspectApedia-911, I was mainly asking about the gray plaster that held it on and if they put asbestos in it

by InspectApedia-911 (mod)

@Derrel,
Our best information on that is at ASBESTOS in PLASTER

Please take a look and let me know what questions remain.

Is this asbestos-containing plasterboard in my 1957 home?

Any idea what this material might be? Kitchen wall in 1957 house.

On 2023-06-13 by Danny

Reply by InspectApedia Publisher - rock lath was used as an alternative to wood or metal lath

@Danny,

Yes, that looks like rock lath or gypsum board or plasterboard that was used as an alternative to wood or metal lath to build a plaster wall or ceiling.

Use the on page search box to search this website for

ROCK LATH to see details

Should we assume there is asbestos in a 1950's ceiling or wall?

For a house built between 1950-1955, should we assume that there is asbestos in the ceiling/walls?

Would you recommend testing walls/ceilings if we intend on putting in pot lights (fairly big holes?), making holes in the wall for electrical work, and maybe breaking down a wall? Thank you On 2021-07-25 by Aaron B

by (mod)

@Aaron B,

I suspect the cost of testing is greater than the cost of treating the material as presumed to contain asbestos when you're making small, limited cuts; keep dust down, wet surfaces, damp wipe, HEPA vac.

by Aaron B

Thank you for the reply, that's very helpful to know. Is something like pot light insertion or let's say 3-4-inch(ish) holes for the purpose fishing electrical wires considered a limited cut? Thank you again, this website is a blessing

by inspectapedia.com.moderator - steps to minimize exposure even with limited cuts

@Aaron B,

Yes those are limited cuts.

Keep in mind that how you make a cut in plaster or drywall and how you control dust make a lot of difference in dust exposure in any event.

Even the difference between using a fine-tooth circular hole cutter at low speed versus a coarse tooth circular hole cutter at high speed is significant.

Your original question I wasn't sure whether we were talking about plaster or drywall / Simpson board.

It's easier to make cuts in drywall with virtually no dust than it is in plaster. But in both cases you can minimize dust, wear protective gear, and keep things in perspective.

by Aaron B

@inspectapedia.com.moderator, Thank you!

1960's Plaster Ceiling / Wall Asbestos FAQs

Question: Do Detroit 1967 "Rock Lath" plaster walls or ceilings contain asbestos?

Note: Original, as emailed photos from the reader and home discussed below have been removed at the reader's request - the reader's close-up photos showed edges of what appeared to be either drywall or rock lath based plaster at electrical box openings such as at a wall plug receptacle and at a light switch - Ed.

Shown here from two different homes, we have provided examples of rock lath, courtesy of and with special thank-you to other InspectApedia.com readers K.K. and C.M.

Anonymous asked:

All of [my photos in my email to you] are photos from a 1967 house we are considering purchasing.

Do you think any of the photos might have asbestos in them?

Some of walls are plaster. Thank you for your input. Ceilings are plaster. Anonymous by private mail 2021/06/22

Moderator reply: asbestos is quite possibly in joint compound used for repairs & possibly in the plaster itself.

No one can say with confidence whether or not plaster, rock lath, or gypsum board drywall have or don't have asbestos based on the photographs that you emailed to us.

We studied with care all of your pictures and could see what appears to be the edge of rock lath and gypsum board at an electrical receptacle, a switch, and at other wall or ceiling openings.

Plasterboard, drywall, and also joint compound used on wall and ceiling surfaces and at joints in the 1960s and up into 1986 might indeed contain asbestos.

If it is not damaged or disturbed, plaster or drywall do not shed any detectable level of harmful dust, asbestos or otherwise.

Asbestos is safe and legal to leave alone in buildings, in fact safer than trying to remove-it, as long as it is left undamaged and in good condition. - US EPA [paraphrased]

However if the plaster is loose, falling, or damaged, or will-be damaged by renovations or other work on the building, its dust can be a harmful respiratory irritant, whether or not it also contains asbestos. 

Watch out: If you are facing such demolition or renovation work it would make sense to either treat these ceilings and walls as if they contain asbestos, to have representative samples tested.

As it will be helpful to other readers, and as its publication may prompt other readers to offer a helpful suggestion, I will include a redacted (to respect your privacy) version of this discussion in our

article ASBESTOS in PLASTER.

Also see ASBESTOS in DRYWALL

Also see PLASTER DUST EXPOSURE HEALTH HAZARDS

Exposure & Risk Levels from Asbestos in Plaster FAQs

We have Chrysotile asbestos "in all our bedrooms"? Is it Dangerous for me to Remove The Plaster?

We have asbestos Chrysotile in all our bedrooms. The lab report says the risk is very low.

The plaster is behind wood chip paper which I am keen to remove. Is this a really dangerous thing to do? Thanks! On 2020-08-28 by Samantha

Reply by mod: Yes it is dangerous and possibly illegal to do your own demolition of asbestos materials

Depending on where you live, demolition of asbestos-containing materials must be handled by a trained, licensed asbestos abatement contractor.

So if you are keen to remove the plaster you're asking for trouble.

Watch out: Doing it yourself not only risks exposing your self and other people to harmful demolition dust, including airborne asbestos, it also risks creating a still more-costly cleanup job to later remove asbestos dust contamination throughout the building. Don't do it. - Daniel Friedman

If you mean to only remove the wallpaper that can often be done without disturbing the plaster one bit, using steam. But don't expect pristine plaster to be revealed. It's likely that repairs will be needed.

Is asbestos dangerous if covered by wood?

It is the dangerous when you covered it with wood. Because were covering it with but we did no know about asbestos until we saw it on TV? What kind of ceiling is? On 2019-07-13 by Anonymous -

Answer by (mod) - generally no, and it is safest to leave asbestos-suspect materials in place

Anon:

In general it's safest to leave asbestos-suspect materials in place, covering over the floor, wall, or ceiling material.

It's not as if it's radioactive; covered = safe, as it's undisturbed and protected from disturbance.

I picked up several chunks of plaster that is falling off - should I be worried about exposing myself to asbestos danger?

I recently picked up several chunks of plaster that is falling off of the wall next to our furnace.

There is lath, a dark brown layer with dark hair in it, and then a thin, white layer on top of it.

I didn't use any precautions and now am freaking out the possibility that it contains asbestos, which has contaminated me and possibly my entire house and family.

There is crumbled pieces of plaster still there that I have not removed. It is powdery now.

Should I be freaking out or is this probably not asbestos containing plaster? On 2018-03-21 by Vickie -

Answer by (mod) - No, don't "freak out" - Just picking up a few chunks of plaster to drop into the trash is not likely to contaminate you at any significant level

Vickie

Just picking up a few chunks of plaster to drop into the trash is not likely to contaminate you, your house, your family - nor would it alone create a measurable airborne asbestos hazard even if the material contained asbestos.

On the other hand, being terrified is itself more-likely a greater health hazard.

Plaster with hair in it is probably quite old - often horse hair was used. I'd like to see some sharp photos of the material - use the Picture Frame icon next to the comment button.

Making a dusty mess, blowing plaster dust about in a home, would be a more serious respiratory concern, even without asbestos.

Asbestos exposure from cutting out a 1950's wall section?

The homeowner from whom I rent cut out a large portion of the kitchen wall. I'm scared he exposed my cousin and me to asbestos given that there was dust following the work, that he vacuumed it with a non-HEPA vacuum, and that there was an air conditioner that we used over the summer after the work was completed which likely trapped dust and aerosolized it.

House was built in the late 1800s and I believe that the wall was renovated in the early-to-mid-1950s. On 2020-12-26 by Timothy Franks

by (mod) - asbestos hazard test for dust from plaster wall cut-out work

Timothy

At this point since the majority of the cutting and cleanup have been done what is left for you to do is either collect a representative sample of settled dust to test for asbestos or representative samples of the wall that was cut out to test for asbestos.

If there is found to be a significant asbestos level in either of those materials then you may want to do some additional cleaning such as damp wiping and HEPA vacuuming

Does old plaster shed harmful dust even when not disturbed?

I live in an 84 year old home that has plaster walls. There seems to be quite a lot of 'Heavy" dust all the time and myself and my daughter, have a cough from it.

Can old plaster 'Shed" and cause respiratory problems?

Someone told me, re-painting can help.

What do you suggest? We have lived here for 5 years and it seems to get worse all the time. On 2021-05-30 by Katherine

Answer by inspectapedia.com.moderator (mod) - plaster dust is a respiratory hazard, asbestos or not; test dust to determine source and type

@Katherine,

If it is not damaged or disturbed, plaster does not shed any detectable level of harmful dust.

However if the plaster is loose, falling, or damaged by renovations or other work on the building, its dust can be a harmful respiratory irritant, whether or not it also contains asbestos.

If by visual inspection you don't see cracked, loose, falling, or cut-into, damaged, disturbed plaster, then that's not the source of your dust complaint.

See DUST SAMPLING PROCEDURE

for a procedure for collecting representative samples of indoor dust (inexpensive and easy) that you can then send to any environmental test lab.

Ask the test lab to tell you if there is a significant presence of unusual particles in the dust sample, and/or high levels of harmful particles like mold, dust mite fecals, allergens, asbestos, etc.

Did my apartment ceiling leak expose me to asbestos? Should I throw out my bed?

My old apartment built in 1900 probably remodeled a bunch since had a ceiling leak.

I didn’t think anything of it until I started reading about asbestos as a new homeowner. Did I have a past exposure to asbestos.

I still have the same bed that the ceiling leaked on should I get rid of it ? On 2020-09-03 by Erika

Answer by (mod) - hazards from leak through ceiling onto bedding and mattress

If a mattress has been wet from plumbing leaks, particularly drain leaks, it's likely to be contaminated beyond economic repair.

Steam cleaning won't reach deeply-enough into a mattress to make it sanitary if it's been contaminated by leakage; the concern, from your photo, is the wetting.

If you're concerned about asbestos in the bedding, you would certainly wash the bed clothes if they haven't already been cleaned.

by Dawn

this is my fallen living room ceiling. Does it look like asbestos?

Reply by (mod) -

In your photo (shown above) that plaster debris looks like traditional 3 coat plaster; please review the asbestos in plaster discussion found at the topic home:

ASBESTOS in PLASTER where we provide data on the use of asbestos in plaster, at https://inspectapedia.com/hazmat/Asbestos-in-Plaster.php

Should I test my antique plaster containing horsehair for anthrax?

Should I test my original plaster cast cornice for asbestos and ceiling lath plaster for anthrax before any work begins to modernise my 1905 house On 2021-03-13 by colm dowdall -

Answer by (mod) - There may be a hazard of anthrax exposure from old plaster that contains horsehair

@colm dowdall,

Thank you for the interesting question that I might re-phrase as "Is there a meaningful hazard of anthrax exposure from old plaster that contains horsehair?"

I am compelled to add that at least in the U.K. there are a number of websites and sources who warn about hazards of anthrax exposure in old or historic buildings.

Be sure to review the source of those assertions and watch for conflicting interests.

The WHO, in comparison, can be expected to be without the OTHER PEOPLE's MONEY motive nor profit motive in giving advice about Anthrax hazards.

In the UK, Bacillus anthracis is subject to COSHH regulations (Control of Substances Hazardous to Health).

Those regulations are more general than the more narrow question of known hazards of exposure to horsehair in plaster.

see

GUIDELINES FOR THE SURVEILLANCE AND CONTROL OF ANTHRAX IN HUMAN AND ANIMALS. 3rd edition. [PDF] WHO/EMC/ZDI/98.6 PCB Turnbull
Centre for Applied Microbiology and Research Porton Down, Salisbury, Wiltshire SP4 0JG, UK original source:
http://www.who.int/emc download also at inspectapedia.com/hazmat/Anthrax-Control-WHO_EMC_ZDI_98.6.pdf

Excerpt: There is, in fact, no conflict between the statements and evidence given in 4.2.1 and 4.2.2 that humans are fairly resistant to fatal anthrax infection and the possible aggressive use of anthrax spores.

The worst case natural contamination in the environment is found at the carcass sites of animals that have died of anthrax.

In a study in Namibia of 106 such sites, the highest contamination level found was just over 1 million anthrax spores per gram of soil, but 79% had less than 1000 per gram and 25% less than 10 per gram (Lindeque and Turnbull, 1994).

Levels in other types of inadvertently contaminated environments (soils at tannery sites, horsehair plaster, etc.) rarely exceed a few units or tens of spores per gram (Turnbull, 1996).

Natural environmental exposure to infectious doses in the normal course of human life and endeavour is, therefore, a fairly unlikely event. - Op. Cit. p. 13

Because horsehair was used in old plaster in many countries including the U.K. and North America and because animal hair can in principle carry anthrax, there has grown up an industry of testing such materials for anthrax before demolition or remodeling.

If you read our article on OTHER PEOPLE'S MONEY inspectapedia.com/home_inspection/Other_Peoples_Money.php

you'll see why consultants asked a question like yours will often spend your money to reduce their risk by saying "YES DO TEST for ANTHRAX"

But I'm still looking for even one scholarly research article that reports even one case of someone contracting anthrax from 100 year old building plaster.

If you have any such authoritative sources please let me know.

We got hives and respiratory trouble renovating our 1930's house - asbestos worry?

I am trying to renovate our old house, supposedly built around the late 1930s or 1940s. Recently my husband and I have been having hives, coughing, generally feeling bad. The temperature outside has been very hot, high 90s.\ I am wondering if there is a connection with the heat ( NO air conditioning) and the plaster itself.

Does it contain asbestos? We were not told of any asbestos in the house when we bought it. What can I do to quickly treat and cover the walls with paint?

I am extremely worried. My husband has cancer. His hives, constant itching is just terrible. PLEASE ADVISE. Thank you, thank you. On 2021-06-13 by Patricia

by inspectapedia.com.moderator (mod) - Hives points to other allergens, not asbestos

@Patricia,

While nobody can give reliable, comprehensive home safety advice from a brief e-text, and thus while I always worry that there are more-immediate hazards (falling down the stairs, fire, etc) in a building than the ones that come to your attention, it is possible to give a few suggestions:

There may be asbestos in old buildings in any of several locations such as plaster, drywall, flooring, pipe insulation.

I have not found any research citing hives as specifically asbestos-related.

But in any old house, the dust caused by demolition and renovation is potentially hazardous as well as a respiratory irritant.

Old house dust, especially if you're demolishing plaster or cleaning up old dusty dirty areas, may include

- lead

- pesticides or other chemicals

- insect fragments and mite fecals and rodent hair or fecals all of which are allergens and potentially more harmful

- silica dust

Start by asking your doctor for advice, including the question of the role that home renovations might play in your medical complaints, as well as the risks of such work for anyone who has cancer and thus, undergoing treatment, may be immune-compromised.

And meanwhile,

- use damp wiping and HEPA- vacuuming (NOT an ordinary shop vac or household vac) to clean up dust and debris from areas in which you are living, starting with the rooms in which you spend the most time

- you can certainly use any low VOC paint with brushes and rollers to paint, or have-painted, ceilings, walls, trim, in those same rooms or in rooms where the ceiling or wall surfaces seem to be shedding material

- Unless there is loose plaster at risk of falling on you, I'd avoid any demolition; often, as you can read in this article series, even loose plaster can be secured to the lath behind it using large plaster washers and screws.

- do not assume that your plaster is the only, or even the most- serious hazard in your home.

- take note of the home's leak history - there could be mold contamination (also something you'd discuss with your doc)

- be sure you have working CO and smoke detectors properly installed, located, tested

Question: was asbestos used in plaster casts?

Was asbestos used in the material used for casts for a broken bone? 2018/09/08 srevesz

This Q&A about the use of asbestos in bone casts or orthopedic casts were posted originally

at ASBESTOS LIST of PRODUCTS

Reply: yes asbestos was used in a wide range of plaster casting including orthopedics

S Reves

Yes, asbestos was used in some plaster cast and plaster mold applications, both directly in forms of asbestos fibres and also in the form of vermiculite, some of which contains asbestos.

There are some patent disclosures and research citing use of asbestos in products applied to splints and casts for broken bones, and possibly also in some denture casts, including those listed above

at PLASTER DUST EXPOSURE HEALTH HAZARDS

Test Results for Asbestos in Plaster, FAQs

Reader follow-up: tested drywall for asbestos - traces of asbestos found in plaster base under drywall

Thanks again for your advice regarding asbestos. I ended up having a sample tested, there were multiple layers as you can see in the piece that I sampled for testing.

The conclusion was that the second layer in from the outside has trace amounts of asbestos.

Way less that 1% the lab tech told me. They are sending the full report through to me later today.

I attached a photo. The side with my thumb is the inside. The thick gypsum part had no asbestos, and the outer (I presume skim coat) has no asbestos.

But popcorny looking part is where the trace amount was found.

As it is less than 1% and the two pieces that I'm removing are 3ft x 7ft, am I am looking for advice regarding best practices to remove it?

As it is a trace amount less that 1% should I just go for it and have no concern? Should I still use extreme care? The stuff does make a pretty dusty mess, so that is my concern,

I live in a neighborhood of 40's houses, and I'm pretty sure everyone around here knocks entire walls down with the stuff falling on their faces, so I may be overthinking this!

Although we did lose a family friend a while back to mesothelioma, so that probably is what is causing my anxiety.

Any advice would be greatly appreciated.

Sean Sullivan

Reply:

Sean, to me that photo - shown above - looks like a layer of drywall bonded over a layer of plaster skim coat over a layer of plaster base coat or of cementious plasterboard. It's the older plasterboard or possibly a skim coat that may contain asbestos, depending on when it was applied.

To be extra careful Sean,

see ASBESTOS REMOVAL, WETTING GUIDE

This plaster was tested for asbestos - not found

Hi there, appreciate the blog and you getting back to individual readers. We have a house built in Central Massachusetts in the early 1960s.

We recently removed baseboards and the plaster behind crumbled in a few spots. Looks like there may be some rock lath underneath.

Don't have a great cross section, but photo attached is up close. For size reference you can see a rusty old nail head. I'm mostly concerned with that pinkish gray layer, which looks like that "brown coat" layer from TD's photo. Any thoughts would be much appreciated. Thank you! b

by InspectApedia-911 (mod)

@Nathan,

As long as we are faced with a very small area such as the one in your photo it may make more sense to treat the debris as presumed to contain asbestos rather than to pay the lab fee to have it tested. Instead you could spend that same cost on damp wiping and HEPA vacuuming and then a simple plaster patch or repair compound spread over the hole.

But arguing with myself just to give another point of view, it might be worth sending out a full cross section of the plaster for an asbestos test.

That will tell you whether you need to take extra precautions in any future modifications, cutting sign or drilling into walls of ceilings etc.

Let me know what you think and what you prefer.

by Nathan

@InspectApedia-911, I decided to get the layers tested. Three layers were tested, the upper layer of white plaster, the rock lath wall, and the fibrous material behind the rock lath. No asbestos was detected in any of those layers. Thanks for your thoughts!

by InspectApedia-911 (mod)

@Nathan,

Thank you very much for following up and taking time to post the test results of the layers of plaster in your home and reporting that asbestos was not found.

That will be helpful to other readers.

Tests for asbestos in plaster found 5-10% Chrysotile 95% Matrix in tile mastic instead

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 On 2021-02-11 by Ben - T

Comment by (mod) - Chrysotile asbestos confirmed in tile mastic adhesive

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

See also

ASBESTOS-CONTAINING MASTIC DANGEROUS?