Whether you’re a professional contractor or a DIY enthusiast, you may have found yourself wondering: does joint compound go bad?
Despite the wide range of formulations available, no drywall joint compound lasts forever. The life of most wet compounds is around nine months to a year if they are stored properly.
Buy only what you need, as excess mud will eventually expire. Joint compound for drywall does deteriorate over time.
A joint compound, also known as drywall mud or spackle, is a critical element in the finishing stages of drywall installation and repair.
It’s designed to create smooth, seamless surfaces on walls and ceilings, providing a foundation for painting or wallpapering.
However, like many construction materials, the joint compound has a limited shelf life, and its usability can deteriorate over time.
Does Drywall Mud Go Bad Over Time?
I would answer yes to this question. There is a natural degradation of drywall joint compound over time. This is due to the natural components this product contains.
They start decomposing quite a long time after being stored, leading to the overall decay of the product.
In other words, you can’t expect your drywall joint compound to retain its quality longer than twelve months, even if it is stored properly.
Also, air exposure accelerates the degradation of drywall joint compounds. It will take time for the contents of the container to become less and less valuable once you open the container.
It’s best to keep your tank with drywall joint compound in optimal conditions in this situation. This means that the container needs to be stored in a cool, dry place, and it must be sealed!
Thus, you will be able to extend the shelf life of your joint compound to the maximum; however, you must discard the joint compound once you see even the slightest signs of decay.
I’d like to take a look at the material data sheets of joint compounds from various manufacturers. According to CertainTeed’s Easy-Fil data sheet, the product is:
Shelf life: 12 months from the production code date when properly stored.
From Certainteed Easy-Fil Product Data Sheet
Therefore, you can expect a shelf life of 12 months if stored properly, which includes keeping it cool and dry without opening it. Based on Certainteed’s data sheet for ready mixed joint compounds, it states the following:
Distribution channels and applicators should have ample time to sell and apply products before quality deteriorates according to the recommended dates by product group
From Certainteed Finishing Product Shelf Life
As you noted above, the joint compound will deteriorate once opened and exposed to air, and it will deteriorate very quickly.
The table above shows that pre-mixed joint compounds should be used within nine months.
9 months, however, is based on mud that has not been opened or stored under ideal conditions. A drywall mud that is opened and stored in less-than-ideal conditions will deteriorate much sooner.
Continental Building Products’ material data sheet relating to ready mix joint compound states:
When the material has spoiled, is moldy, or has an unpleasant odor, you should not use it. Hence, yes. Mold will develop on drywall mud when it begins to “deteriorate” or decompose.
The Shelf Life of Drywall Joint Compound
The joint compound for drywall comes in many formulations, but none of them last permanently. The mud can dry out over time, become mouldy, or become otherwise unusable.
Keeping it in the proper condition dramatically affects its shelf life. Various factors influence the shelf life of drywall compounds, resulting in an unpredictable life expectancy.
Air
There is a great deal of air in the drywall compound, which poses a significant problem. Air will dry it out, and it will become unusable quickly if it is exposed to it.
In some cases, only the top of the compound will dry out, and if you remove it from the container, there may still be usable mud underneath.
When stored in a completely sealed pail, your mud may last much longer than if kept in less secure containers.
Mold
After opening a package of drywall compound, contaminants are exposed to the product. An open compound is more susceptible to microorganisms. It could result in mold growing on the compound if it is stored once again.
The compound used to manufacture some types of drywall is specially designed to resist mold growth. These products may damage walls that are exposed to moisture, especially in bathrooms and kitchens.
The built-in mold resistance of these compounds helps make them last longer than other compounds.
Water
Store your mud in a pail that you can seal tightly and then layer it with water to increase its shelf life. It keeps the compound from drying out, so it’s still usable when needed.
When using this option, do not throw a dirty drywall knife into the bucket or re-use the compound once it is removed.
Adding water to a container helps prevent contamination, which is essential since water speeds up mold growth.
Other Signs of Spoilage
Besides expiration dates, there are other indications that the drywall mud is no longer usable. A strong smell comes from the mud when it has started to spoil, a scent that is different from its typical smell. In addition, expired mud has an uneven color or has changed colors completely.
Lastly, ensure that the expiration date is accurate. A weak job is likely to be compromised if you use expired mud or mud with visible spoilage signs.
How Long Does Drywall Joint Compound Last?
As long as you store the drywall compound under the correct conditions, you should be able to keep it for years.
The reality is that this powder will only remain good for a very short period before it starts losing quality!
You will likely find the expiry date set by the manufacturer on the bucket that your joint compound was sold in.
The date, in the case of this product, refers to the period during which you should use the whole container. The compound will start degrading slowly if you do not perform this step.
The warranty that worked for the valid product will become invalid if the product is past its expiration date.
As soon as a joint compound expires, its potency and strength will decrease. Aside from that, it will dry quickly, so it will be risky to apply!
As such, if you want to be sure that you are using a product with the best quality that will last a long time, double-check whether your drywall compound is still usable.
How Long Does Unopened Joint Compound Last?
If you accidentally bought too much joint compound and realized that it will not be able to be used right away, you will have to save it somehow.
You need to know exactly how long this stuff will last in your basement or wherever you plan to keep it.
If we are discussing drywall mud, your unopened container with joint compound should keep its quality for nearly 12 months (from nine to twelve months).
Powdered compounds have approximately the same lifespan but do not last longer than one year!
How Long Does a Used Joint Compound Last For?
How about if you have already opened the joint compound tank and used parts of it for your renovations? Is it possible to still use the rest later? How long does it keep at home without losing its potency or quality?
In all honesty, we wouldn’t recommend using drywall joint compound (wet, dry) if the container is already open.
Once unsealed, this product tends to deteriorate far faster than it would if it were in a tightly sealed container.
Additionally, even if your joint compound lid is tightly closed, air will get into it regardless.
In addition, the air exposure will have an adverse effect on it. The joint compound will become dusty and hard much more rapidly in the presence of air. Additionally, mold spores will be more likely to congregate there.
How Long Does Powder Joint Compound Last?
There is good news for you if you have a batch of powder drywall joint compound left over from your recent home renovation, and you need to find out how long it will last until it needs to be thrown away.
Powder joint compound in an unopened container can remain beneficial for nearly twelve months if stored correctly. This way, you’ll know the walls will still look good if you decide to refresh them in the future.
How Long Does a Pre-mixed Joint Compound Last?
There is not much difference in shelf life between pre-mixed joint compounds and this product’s powdered and liquid forms.
A pre-mixed joint compound may take nine months to get old if it has not yet been opened.
As such, you must use the product within the given timeframe. In addition, if the product is kept correctly, its qualities will remain intact!
For a complete understanding of the storage and shelf life of the drywall joint compound, we recommend you check out the comparative chart, where you can find the expiry dates for any variety.
Final Words
Now that you know how long drywall compound lasts and how to store it effectively, you know what conditions must be met for it to last.
