Questions & answers on stamps and codes used to identify drywall or gypsum board manufacturer and productrion date.

This article series discusses the identification and history of both modern and older interior building surface materials such plaster and lath, Beaverboard, and Drywall - materials that were used to form the (usually) non-structural surface of building interior ceilings and walls. Our page top photo shows hand-split wooden lath backing for a plaster interior wall.

Drywall Identification Stamps & Codes FAQs

These questions & answers about identifying various drywall or gypsum board products by stampsl found n the back surface were posted originally

at DRYWALL TYPE IDENTIFICATION STAMPS - be sure to review the drywall identification help given there.

[Click to enlarge any image]

On 2021-08-18 by inspectapedia.com.moderator

@Kirsten,

Thank you for the follow-up as I will help other readers. If I understand the question correctly you are working on the cavity side of the drywall that we are discussing.

In that case one must ask if the building department would have accepted you installing fire rated gypsum board either in the cavity against the existing drywall or on the other , exposed side of the same wall.

On 2021-08-18 by Kirsten - intumescent paint permits avoiding kitchen cabinet tear-out

@inspectapedia.com.moderator, Thank you for the response! Bummer the patent couldn't be tied to a fire rating. The drywall you see is the back of my kitchen with a whole row of kitchen cabinets behind them. So to replace that drywall, I would need to tear out the kitchen cabinets.

However, I had some success with my building department who is going to allow me to use intumescent paint in that wall cavity and not make me replace with type X. So paint in the cavity and then type x on top to reclose the wall (if that makes sense). Woohoo! Thanks for the help. This site has been a great resource for me through this project!

On 2021-08-18 by inspectapedia.com.moderator (mod) - patent number research sometimes can identify asbestos-containing materials or fire-rated drywall and can ID its age

@Kirsten,

A quick patent search finds

• Johnson, Gordon C., and Samuel Sterman. "Process for sizing paper with epoxy silicone and resulting products." U.S. Patent 3,431,143, issued March 4, 1969.
• David, Bieri, and Edward S. Coia. "Gypsum wallboard and method for producing same." U.S. Patent 3,389,042, issued June 18, 1968.

Neither of these patents address fire resistance nor even use the word "fire" in the patent disclosure. They do give a floor to the possible age of your drywall. It would not have been made before the dates of patents whose number are stamped on the product.

Perhaps if you say more about why you'd have to demolish an entire kitchen wall we can offer more advice. That sounds, frankly, a bit extreme.

Seems more-likely you could, at worst, add a layer of fire-rated drywall somewhere on the wall structure.

On 2021-08-17 by Kirsten

I am trying to ensure there is a firewall (fire rated drywall/type x) between my two units so I can reclassify my property as a duplex. We have had luck in finding most drywall on the shared wall is Fire Rated. However, there are a few sheets that have us stumped as we can only find patent numbers.

If we can prove these are fire rated, it would allow us to avoid demo-ing a whole wall in our kitchen. Does anyone know if there is a database or somewhere where I can find info on these patent numbers? I have had no luck on google. It is 5/8" drywall. Any help appreciated. Thanks!

On 2021-08-14 by inspectapedia.com.moderator (mod) - Undewriters Laboratories Inc. Fire-Rated Drywall Identification stamp

@Tyler,

It could contain asbestos, depending on the age of your drywall.

Look for manufacturer's identification in other stamps on your drywall and let us know what you find.

Please see details at ASBESTOS in DRYWALL https://inspectapedia.com/hazmat/Asbestos_in_Drywall.php

On 2021-08-14 by Tyler

Does this drywall contain asbestos?

On 2021-07-17 by (mod) 1970s drywall stamped #13163R x

@Kirsten,

I agree it's possible that that little "X" might indicate fire rated drywall on a 1970s gypsum board, but the rest of the numbers look like a production run not a manufacturer identification stamp. I wouldn't rely on that X , I would look for other stampings identifying the manufacturer and standards that applied.

Also see if you can find the printed end tape on the drywall ends if they're exposed anywhere in your duplex.

On 2021-07-17 by Kirsten

I need to prove or add type x drywall on some common walls in my duplex. I found this marking. Does anyone know if that small "x" at the end is proof that this is type x? We have found other areas with more obvious type x. Likely from the 1970s.

On 2021-07-08 by (mod) - decode stab at alphanumeric drywall stamp 090600225KEL23:12

@Matt,

Translating identification stamps on drywall is made a bit tricky in part because depending on the age of the product its ID stampings may comply with different standards. You'll see that in the variation in the drywalls ID stamps given in the article above.

According to the U.S. Gypsum Association, in 2011, Specification C1264 for drywall was modified to require each individual sheet of gypsum board manufactured to comply with Specification C1396 to have the following information legibly printed on the back surface of each board, parallel to the bound edge of the board:

- The name of the manufacturing company
OR

- a unique alpha code identifying the name of the manufacturing company.

The decision to print the name of the company or to create and use a unique code is at the discretion of the company.

The standard also requires:

- A code identifying the manufacturing facility and, where applicable in a multi‐line facility, the production line. (that's why your code contains 3 alphabetic characters)

- A code identifying the date and time of manufacture.

- The country of manufacture as designated by the three letter code in ISO 3166‐1

So looking at your drywall, in general tge date code contains the identification of the plant at which the drywall was manufactured, (not an actual text string naming the manufaccturer) - so to be sure we have the code translated exactly correctly we usually have to get to the manufacturer itself.

In your photo I think I see the following date code:

090600225KEL23:12

September 06, 00 [probably 2000]

0225 - uncertain - possibly production line machine ID

KEL - Manufacturer ID and plant ID

23:12 the hour of production

Look for the Paper End Tape on Your Drywall

If you can pull back insulation at a location to show the end or edge tape on the drywall often you will find the product manufacturer's name printed there.

The end tapes on most manufacturers contain the following information, using and excerpting from drywall ID information from CertainTeed drywall as an example:

- Name of manufacturer

- Brand or product name

- Overall dimensions [thickness and length] as well as a set of lettings describing the edge detail. Most gypsum board is tapered edge, or TE.

- End tapes are also color coded per product, so they can be readily identified from a distance or when in storage.

Many drywall products that use a tapered edge (to provide space for taping and finishing edge butt joints) also imprint there similar manufacturer information, but once the drywall is installed and taped you won't be able to see that data.

Many drywall products also include the UL label or stamp information giving the UL listing or standard with which the drywall complies. This can identify fire-rated drywall, for example.

Some specialty drywall products such as tile backer boards do not use paper end-tapes but instead print the product identification in an inked band across the drywall surface.

On 2021-07-08 by Matt

Hello:

Can anyone help identify where this drywall was manufactured?

On 2021-04-17 - by (mod) -

@Jeff, thanks; do let us know the test result as that will help other BC and other Canadian readers.

On 2021-04-17 by Jeff

thank you for taking the time to post your opinion on my question. I will send a few samples off before proceeding

On 2021-04-08 - by (mod) -

@Jeff,

Here is what we know about ASBESTOS in CANADIAN DRYWALL https://inspectapedia.com/hazmat/Asbestos-in-Canadian-Drywall.php

In a 1975 house, unless you know this drywall is from the 1996 renovation, you'd treat it as presumed to contain asbestos - or if that means facing a big cost, have samples of the drywall AND of joint compound tested for asbestos

You can find ASBESTOS TEST LABS in the ARTICLE INDEX

On 2021-04-08 by Anonymous

@Jeff, here is another pic

On 2021-04-08 by Jeff

Hi, I’m currently starting a Reno on my home and have come across some gyproc that I don’t want to mess with until I have a better idea of whether or not it might contain asbestos. Any insight is appreciated. House was built in 1975 in Victoria bc Canada, and had some sort of Reno in 1996.

Thanks in advance

On 2021-04-08 - by (mod) -

@Chris bridges, the chances that your fire-rated drywall contain asbestos are good if it was made in North America before ca 1986

On 2021-03-29 by Chris bridges

On 2021-02-28 - by (mod) -

@Den Clark,

Also see Canadian DOMTAR Drywall

https://inspectapedia.com/interiors/Drywall-Manufacturer-Identification-Stamps.php#Domtar

On 2021-02-28 by Den Clark

Yes, the house was built around that time.
I appreciate you taking the time to answer. Thank you.

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

@Den Clark, I can't identify the manufacturer of your drywall although it's certainly likely to be a Canadian one. From the number I suspect that it was manufactured in 1986. Is that consistent with the age of the building where it's installed?

On 2021-02-22 by Den Clark

I am trying to indentify if some drywall we have from a house we bought in BC Canada has asbestos. There is a stamp on the back but no other id marks on the back or sides. I have attached a photo. The number as I read it is 8612160631B Any assistance is appreciated. Thank you.

On 2021-02-16 by Anonymous

will most surely do that! I will get specifics/dates and include that information

On 2021-02-14 - by (mod) - owner of the UPC code is Lafarge Corporation who sold their gypsum board business to Continental Building Products. It was then sold to CertainTeed.

Thank you for the follow-up, Jennier; I'm glad to offer what assistance we can, without bias as that makes it more-useful;

working together makes us smarter.

If you have dates or references for the Lafarge sale to Continental Building Products and for the subsequent sale to CertainTeed those would be helpful to add here (this page)

or at DRYWALL & GYPSUM BOARD COMPOSITION & HISTORY - composition & History

https://inspectapedia.com/interiors/Drywall-Composition-History.php

On 2021-02-14 by Jennifer S

I can’t even begin to thank you for all the research you performed on my behalf. It provided help beyond measure. I did discover the owner of the UPC code is Lafarge Corporation who sold their gypsum board business to Continental Building Products. It was then sold to CertainTeed.

I am trying to get information from them now. Thank you again @danjoefriedman. Every bit of info and detail and resource your referenced made this painful, stressful task where I was completely at a loss and had no understanding of until no so easy.

On 2021-02-11 - by (mod) -

Jennifer

Please find your recently-posted question(s) or comments and photos along with our reply now at the Reader Q&A section near the bottom of the article above on this page. You may need to clear or refresh your browser cache to see the updated page. We welcome your further photos, comments, questions.

On 2021-02-11 by Anonymous

I can’t even begin to thank you enough for your reply. Our homebuyer of 2.5 years ago is suing us saying we hid structural issues beneath this gypsum board which they state was manufactured in 2008. We never installed any gypsum board and have been intimidated that this buyer (an attorney himself) is claiming that since we lived in the house in 2008 that this (based on the UPC code) gypsum wallboard was purchased and installed that year.

This is simply a lie. I didn’t know how to research anything of this nature which is foreign to me. We hid nothing but were confused that he said he found this tag on the back of the gypsum board and it proved we installed it in 2008 which we didn’t do at all

. We feel he is just trying to get us to pay for an expensive remodel (and the house is historic being built in 1844) All we ever did was apply two coats of paint during the years we lived in the house on the walls. One last question - based on the CSA number are you saying that the gypsum board was last withdrawn in 1991?

On 2021-02-11 by (mod) - history of use of UPC and Standards Stamps on Drywall vs Drywall Age

Jennifer

Thank you for the important and troubling question. I've done some additional research on the relationship of drywall identification stamps, standards, and UPC codes and their role in dating or setting thte age of specific drywall or gypsum board products.

The earliest drywall identification stamp I've seen was from 1894.

Dates of Drywall Standards: You'll see in recent comments on this page, that we can sometimes make a reasonable guess at the age range for a drywall product by noting the dates at which standards cited in a drywall stamp or imprint were first published or last withdrawn.

Patent research: And sometimes we use patent research to get a similar "oldest" or "newest" plausible age.

The use of UPC: Universal Product Codes found on drywall can set a "no older than" date in the U.S. as the mid 1970s. It might be possible to trace a specific UPC to a specific production lien of drywall made by a particular manufacturer, though often those UPCs are likely to appear on a product over quite a few years.

Those tools are reasonable in that no one could successfully argue that somebody put up drywall in 1954 that bears a standard ID or number that was first published in 1985.

But all of those analyses are accurate only to a range of dates, not to a precise date.

Corroborating Evidence of Drywall ID & Age: For that reason I typically advise readers who have some reason to care for a more-accurate date of any building material to review

- the original date of building construction

- dates of and records of building modifications

- the plethora of surrounding building age clues that we give starting at AGE of a BUILDING, HOW to DETERMINE - home

Pending further research on the use of drywall stamps, I note that my OPINION, having looked at this topic for some years now, is that there is not consistent use of drywall stamps and identification markings; there is wide variation in when product information is applied and also how it is applied: ink stamps, paper labels, tear-off strips on the bottom edges of drywall, etc.

It varies considerably by manufacturer.

But I can assure you that while we may find gypsum board or drywall that bears no identification mark, for at least some manufacturers, product identification stamps have appeared on the back side of lots of drywall in the U.S. since 1912 or earlier.

Those stamps, as you'll see in this article series, appear in a wide range of formats, colors, and vary considerably in what information is provided. Some, not all, include reference to fire or other classifications.

What is the actual issue here? Can we get that clarified? If so we might conclude that the age of the drywall is completely irrelevant or there may be other more-direct methods of answer the question of who did what when to the building.

Also see the historical data on drywall composition and uses at

DRYWALL & GYPSUM BOARD types, age, history.

The first use of UPCs or Universal Product Codes in the U.S. was in 1974. Source: "The History of Barcodes" - https://www.barcoding.com/ where we read that barcode readers have been in use in the U.S. since 1952, and that UPCs came into first use 22 years later.

What I take from this is that if drywall in your home bears a UPC, from that information alone, that is without tracking down the specific drywall manufacturer's use of a specific UPC Number, the drywall could be as old as the 1970s.

Finally: from what you've told me, and without any onsite data, I'm tempted to reply to the current owner's attorney: "You're just fishing, and ... there's no fish in this water."

On 2021-02-11 by Jennifer S - gypsum board dating, what the standards are for date stamping and manufacturer on the back

Regarding gypsum board dating, can the moderator comment on what the standards are for date stamping and manufacturer on the back of it. A home buyer of ours from years ago is suing us for fraud saying we put up drywall to hide defects stating that “based on the UPC code” it was purchased in 2008 or later when we resided in the house.

The home buyer is a less than scrupulous attorney who seems to be pulling out whatever stops he can for us to pay for his expensive renovation of a home dating back to 1844 - bee hive ovens and all.

We lived in the house for 16 years and the only thing we ever did to the drywall that existed on those walls when we purchased the houses was update colors twice. Can the moderator or anyone else who has knowledge kindly weigh in on how drywall can be legitimately dated and is it standard in the industry (and for how long) that dry wall be date stamped in the United States? We are truly at a loss.

While we realize that we did not install this board, when this buyer intimidates us through UPC codes stating it was manufactured in 2008 or later it makes no sense. We didn’t install drywall. Can anyone kindly weigh in on this? In my research I learned that certain markings started in 2011 and 2012 due to a drywall act, but was it standard in the industry that drywall as far as thirty years back could have a date stamp/manufacturer on the back? So many thanks

On 2021-02-10 by (mod) - how does a building standard "withdrawn" date help identify drywall age? Forensics of drywall age and history determination in a home.

Jennifer:

I'm not saying that gypsum board itself was last withdrawn in 1991. I'm saying this:

If a building standard was withdrawn in 1991, and if drywall bears a stamp saying that the product complies with a now-withdrawn standard, the MOST LIKELY (but not absolutely certainly) the drywall was manufactured before that withdrawal date.

My reasoning is that a manufacturer is more-likely to stamp their drywall with references to standards that are active at the time the drywall was manufactured.

The reason I emphasized "most likely" is because I am not aware of anyone who is policing the timeliness of or use of drywall stamps by manufacturers. To get further on this question you'd need to contact the specific manufacturer of your specific drywall and find someone who knows how that producer uses and applies product stamps, and then get them to clarify exactly when they stop using or update the text in the stamps they put on their products.

An alternative, more-forensic approach to answering the assertion by someone that drywall in your building has been removed and replaced might be possible by observing variations in drywall fasteners and in nail or screw hole patterns in wall studs that might be exposed when the current drywall is removed.

For example, , during its long life, the wall coverings in your home were changed just once from plaster to drywall, then when we remove the current (and old) drywall we might see on the faces of the studs the marks where plaster and lath were removed, and we might see a single set of matching screw or nail holes that fit exactly the drywall that has just been removed.

Of course nothing would prevent there having been multiple generations of drywall installed, removed, installed-new in a home that is more than 150 years old!

On 2021-02-10 by Anonymous - home buyer claims cover up is "proven" by drywall date stamp

I can’t even begin to thank you enough for your reply. Our homebuyer of 2.5 years ago is suing us saying we hid structural issues beneath this gypsum board which they state was manufactured in 2008.

We never installed any gypsum board and have been intimidated that this buyer (an attorney himself) is claiming that since we lived in the house in 2008 that this (based on the UPC code) gypsum wallboard was purchased and installed that year. This is simply a lie.

I didn’t know how to research anything of this nature which is foreign to me. We hid nothing but were confused that he said he found this tag on the back of the gypsum board and it proved we installed it in 2008 which we didn’t do at all.

We feel he is just trying to get us to pay for an expensive remodel (and the house is historic being built in 1844)

All we ever did was apply two coats of paint during the years we lived in the house on the walls.

One last question - based on the CSA number are you saying that the gypsum board was last withdrawn in 1991?

On 2021-02-10 by (mod) - Noting standards-compliance stamps on drywall might help bracket the drywall-age and purpose

Jennifer:

Here's a clever detail: C36/C36M-03e1 Standard Specification for Gypsum Wallboard was withdrawn in 2005, so while we don't know when your particular piece of drywall (gypsum board) was manufactured, it's reasonable to GUESS that it was in or prior to 2005. [OR that the manufacturer has not updated their product labeling. ] Source: ASTM, https://www.astm.org/Standards/C36.htm

ASTM C1396 / C1396M - 17 Standard Specification for Gypsum Board remains active.

The other standards cited CSA A82.27 was published in 1991 and has also been withdrawn.

CAN/CSA-A82.27-M91

Gypsum Board Covers requirements for gypsum board designed for use with or without the addition of plaster, for walls and ceilings.

Status: Withdrawn - source: https://www.scc.ca/en/standardsdb/standards/4876

NYC BSA#682-56-SM a New York City drywall standard is, unfortunately far more difficult to research thanks to the similarity to BSA - Boy Scouts of America

On 2021-02-10 by Jennifer S - tell me the dates of production of this particular gypsum board?

Can someone tell me the dates of production of this particular gypsum board? Would anyone know if gypsum board is required to be date stamped on the back? Thank you very much.

On 2021-02-10 by (mod) UL Stamped Classified Wallboard R-3501, 5/8" Fire Resistance Classification Asbestos?

Ben

When you see fire resistant gypsum board or wallboard from before 1980s you must consider that it may contain asbestos as might the drywall compound used on the board joints. To know for certain you would need to have representative samples tested.

On 2021-02-09 by Ben

Just wondering if this contained asbestos.

On 2020-08-08 by (mod) -1990s Canadian WINROC drywall identification by end stamping

Rob: any other stamps or markings? Patent nos. ?

On 2020-08-07 by Anonymous

@rob,here is a picture of the stamp on side [above]

On 2020-08-07 by rob

We are doing renovations on our 94-95 built cabin..so the drywall should be around this period.

It is from WINROC and a has that company name on edges and barcodes like 726770133 and on side too is a stamp like attached.

So hope I am asbestos free and can take to dump and show this info? comments?

On 2020-08-03 by S.T.

The patent numbers are 1029328, 1034746, 1330413, 1358508, and 1383249.

The house is in a fairly remote mountain area of Placer County, California.

The county assessor dates my house at 1932 but it and the parcel weren't taxed separately from the parcel it was subdivided from in 1931until 1964. The house was built out of a deconstructed 1897 hotel.

Newspaper mentions document that the hotel was taken apart in 1907 so I know the house was built after 1907. Photos of the construction groundbreaking show the original owner/builders in clothing characteristic of the 1920's and a later photo shows the house with very mature vegetation and a vehicle with 1938 registration.

The house was built by a longtime company superintendent and the land that was deeded to him and his wife was part of the greater property and business he managed for them. In the industry it was typical for employees to live on the company property and I suspect the house was built before he was deeded the property.

It's difficult to know if later patents would be attributed to that product and USG doesn't have a historian or archivist to help with dating it. Sorry to be vague about the location and company's industry, it is somewhat unique so, for security purposes, I don't want to publish that. Thank you

On 2020-07-24 (mod) - US Gypsum Sheetrock - "fireproof wallboard" identification - 1920s vintage per patent research

S.T.

Thank you for the photo and question about US Gypsum Sheetrock - "fireproof wallboard". I'll see what else I can find and would like to know what other indicators you've used to narrow the age to between 1907 and 1932.

You used one of my favorite tricks to look into the age of this material: patent number research. The 1921 patent means that the oldest this sheetrock could be is 1921.

Tell me the location: country, city, and what you can about the building where it's installed.

Please also tell me all of the patent numbers, as the photo is a bit blurry even at full size.

On 2020-07-23 by S. T.

Hello and thank you for the informative site!

I'm looking to find any information about the Sheetrock that appears to be part of the original design and build of my house. The house was built with all recycled lumber and, at this time, the Sheetrock is the only material I can identify that might be able to date when it was actually built. Other indicators have only narrowed it down to between 1907 and 1932!

It is 1/4 inch USG Sheetrock with a light orangish color label running the length of the panels. The latest patent date listed on the label is for a 1921 patent. There are no other labels visible and no date stamps to be seen. Any information on dating this product would be greatly appreciated.

Thanks in advance!

I have a house in California that was constructed out of used lumber with its interior finished in 1/4 inch Sheetrock.

I'm interested in figuring out about when the house was built. The Sheetrock appears to be original to the house's design plan. Any help with dating the Sheetrock would be much appreciated.

It has an orange colored label running lengthways on the panels with the latest patent number being for a1920 patent. There are no other labels visible anywhere and no date stamp to be found.

Thanks in advance!

On 2020-07-21 by RICH

I have a drywall board I can not identify. Please help. It only has 1116-1225-1004 RCD
Anyone know what this means?

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

Savannah,

I think the number that you are citing from drywall is probably a production run number or possibly production date. Unfortunately I can't identify the manufacturer or specific product from that alone. It'll be prudent to treat the drywall is presumed to contain asbestos which means that it's perfectly safe to leave it in place as long as you're not doing a demolition and creating a Dusty mess.

On 2020-07-07 by Savannah Slusarski

hi there so we are looking around our house built in 1975 and I found what I believe to be original drywall and it says best wall the # on it is 071004xm. Does anyone have any data on this? I haven't been able to find anything on this. TIA

On 2020-05-19 by Dale

Hi, I'm trying to find out if my drywall contains asbestos. This is the number stamped on the back: 12061SYB1. Any help would be appreciated.

On 2020-05-08 - by (mod) -

Those are probably patent no. dates, Annie.

Sure, the home could be older than those dates.

On 2020-05-08 by Annie

Hi, I found this drywall while renovating my house. I really need to establish the construction date of my house and I don't know what to think of all these years. Should I consider the last date, or could it be older than the last date? Many thanks!

On 2020-03-31 - by (mod) - can you help me identify the manufacturer or brand of this drywall?

Duane

please take a look at DOMTAR GYPROC ASBESTOS? https://inspectapedia.com/hazmat/Asbestos-in-Canadian-Domtar-Drywall.php

and don't hesitate to ask follow-up questions

On 2020-03-31 by Duane Dubyk

Trying to determine if old drywall contains asbestos. Part number on one sample is C060983-17

 

On 2020-03-13 - by (mod) - GPFS-3 Georgia Pacific drywall IDentification

Anon

GPFS-3 may be a Georgia Pacific drywall product, and FS could be fire-resistant - I tried searching the GP site without success but you might give them a request message at https://www.buildgp.com/contact-us/

On 2020-03-12 by Anonymous "TYPE GPFS-3" and "ISSUE NO. B-2721"

wallboard is stamped "TYPE GPFS-3" and "ISSUE NO. B-2721". I need to figure out what kind of drywall this is.

On 2020-02-07 v- by (mod) -

Anon, as the Add Image button doesn't accommodate documents or other forms, please use our email found at the page top or bottom CONTACT link

Thanks

And thanks for the important follow-up

On 2020-02-06 by Anonymous - no asbestos in wallboard with orange patent numbers

Dan, I sent my sample in for testing regarding the wallboard with the orange patent numbers and it came back negative. The report is added.

On 2020-01-22 - by (mod) -

Thanks for that helpful update, Quetzo, I've added your note into the article above.

On 2020-01-22 by quetzo_van - Vancouver BC drywall identification

In response to the (mod) who took a look at the pics of my board with no fire-rating stamps of any kind on it - the house is located in vancouver, bc, canada, and the install happened likely before 1986 (so 34 years old now). The home is 97 years old, built 1923. Not sure that helps...?

On 2020-01-18 - by (mod) -

Thanks for the Bestwall patent details, Nick, I've added them at

BESTWALL DRYWALL ASBESTOS

On 2020-01-17 by (mod) -

Thanks for the images, Nick/Oswana21

In addition to adding them to the DRYWALL TYPE IDENTIFICATION STAMPS page I'll include what you've provided at

BESTWALL DRYWALL ASBESTOS

where I've made a separate page for Bestwall and its history.

Your photos show by edge view what looks like a paper covered gypsum board so it's not likely that your wallboard is the earliest (sawdust and gypsum-based) version of BestWall - as we guessed, perhaps from the 1950s or even later.

If you are able to find a stamping specifically saying "Bestwall" that would be helpful.

I can't make out all of the text in your images; if you can translate it do let me know what it says - as much as you can.

Patent numbers are also helpful for research.

I did see the words New York on one of your stamps.

Bottom line: treat the drywall as presumed to contain asbestos or have a sample tested.

Your gypsum board may be quite old - dating probably from the 1930s to 1950s. Certainteed purchased Beaver Products in 1928.

Certainteed's Bestwall Gypsum board contained asbestos through 1976 or possibly 1977 depending on when the product installed in that year may actually have been manufactured. You should also consider that joint compound used with the product may also have contained asbestos.

On 2020-01-17 0 by Nick

Recently began to take down some old gypsum and I noticed that it said "Certain-Teed Beaver Gypsum Fireproof. Does anyone know anything about this?

On 2020-01-15 by (mod) - Asbestos in this Canadian Drywall? Type C fire rated drywall (Improved Type X)

I can't say for sure if that gypsum board contains asbestos, but indeed some detail about the CAN/CSA standard A82.27 addresses fire-rated gypsum board, SOME of which products, depending on when they were made and by whom, could contain asbestos.

I think that's a Type C gypsum board.

Type C fire rated drywall (sometimes referred to as Improved Type X) is similar in composition to Type X, except that it has more glass fiber reinforcement and other ingredients in the gypsum core that makes its fire resistive properties superior to Type X.

Type C gypsum board is available in 1/2-inch (12.7 mm) and 5/8-inch (15.9mm) thicknesses. - source FIRE RATED GYPSUM, Certainteed https://www.certainteed.com/drywall/what-fire-rated-gypsum/

It would be helpful to know the age of the product or at the very least the age of the building where it was installed and a guess at when it was installed.

CAN/CSA-A82.27-M91
Gypsum Board
Covers requirements for gypsum board designed for use with or without the
addition of plaster, for walls and ceilings.

Status: Withdrawn
SDO: CSA
Language: English
Publish date: 1991-06-30
Supersedes: A82.27-M1977
Keywords: BOARDS, COMPOSITION, CONSTRUCTION MATERIALS, GYPSUM, PHYSICAL TESTING,PLASTERBOARD, STRENGTH OF MATERIALS, SURFACE TREATMENT, WALLBOARD
ICS Codes: 91.100.10;
Standard Number: CAN/CSA-A82.27-M91

See details at CANADIAN DRYWALL ASBESTOS

AND

CANADA ASBESTOS REGULATIONS

On 2020-01-15 by quetzo_van - drywall in 97 yr old house in Vancouver, BC, Canada.

Hey all, Enjoyed looking through the pics to see if my boards are similar, but no!

Trying to determine if this can safely go in a landfill or needs asbestos/hazardous waste protocol...? Pulling down various drywall bits from renos over the past 10~30ish years in a 97 yr old house in Vancouver, BC, Canada.

Above: Text: 85V332W08 MADE IN CANADA

Below: Another pic of a diff type of drywall board... same reno. Thanks. Text: BORD AMINCI ... 2424 Chemin Lakehorse Quest., Mississauga, Ont. L5J 1K... ... POUR SUPRASSER LES NORMES CANSA-A82.27 et ASTM ...

On 2020-01-14 by (mod) - If you don't see a UL classification, a Type X or Type C or U495 and V416 stamp,

If you don't see a UL classification, a Type X or Type C or U495 and V416 stamp,

Then I would assume that the drywall is not fire rated or that it was made before those US stamps and datings were used.

It would be helpful to know the country and city where the drywall is located and the age of it or at least the age of the building.

On 2020-01-14 by (mod) -

I don't think those characters identify the manufacturer explicitly but probably do identify a production plant and perhaps encoded date and time.

If you don't see a UL classification, a Type X or Type C or U495 and V416 stamp,

Then I would assume that the drywall is not fire rated or that it was made before those US stamps and datings were used.

It would be helpful to know the country and city where the drywall is located and the age of it or at least the age of the building.

On 2020-01-21 Reader Follow-up re the drywall above: no asbestos - Vancouver BC

In response to the (mod) who took a look at the pics of my board with no fire-rating stamps of any kind on it - the house is located in Vancouver, BC, Canada, and the install happened likely before 1986 (so 34 years old now). The home is 97 years old, built 1923.

On 2020-01-14 by Mark Fricke

Trying to identify the fire rating for this dry wall these are the only makings I could find.

On 2019-03-11 by Shawn Haag

Can anyone identify the date of manufacturing from a stamp on the back of drywall that appears thusly:

Caledonia East 88 02 22 02 26 B
IMAGE LOST by older version of Comments code - now fixed. Please re-post the image if you can. Sorry. Mod.

On 2018-11-25 by (mod)

Ellen

I could just make out a big red e. Not the rest of the text. It is a stamp that I have not seen before so I'm not sure who's drywall or gypsum board that is. If you can remove pieces without making a Dusty mess you're pretty safe in any case.

If you've read these articles you know that the main Hazard is in the joint compound and in particular if you use a power saw or grinder or sander.

If I had to remove a piece of drywall like that I would probably use a utility knife and pull it from the wall using an approach that did not break it into pieces and I would certainly not use a power saw. You can also reduce hazards by wedding.

And you can also clean up dust by HEPA vacuuming

On 2018-11-25 by Alan

Hi
I'm trying to check my drywall before I remove it. There is a small inspection hatch.

I could not see any brands , just 6 inch high red letter
E38192s

IMAGE LOST by older version of Comments code - now fixed. Please re-post the image if you can. Sorry. Mod.

...

Continue reading at DRYWALL TYPE IDENTIFICATION STAMPS - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• ASBESTOS in DRYWALL
• DRYWALL, FIBERBOARD, PLASTER INTERIORS - home
• DRYWALL & GYPSUM BOARD COMPOSITION & HISTORY - composition of drywall & drywall history
• DRYWALL MANUFACTURER IDENTIFICATION STAMPS & DATE CODES 
• DRYWALL TYPE IDENTIFICATION STAMPS
• GYPSUM BOARD GYP ROCK SHEATHING
• GYPSUM BOARD PLASTER LATH SYSTEMS
• PLASTER TYPES & METHODS in BUILDINGS

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