A gypsum-based paste that is used to finish drywall joints and corners, trim and fasteners, as well as skim coating in new drywall installations is known as the drywall compound (mud).
It’s actually very useful as it protects the wiring and the structural supports in your wall from debris and moisture and also seals the drywall from invading by any insects.
Does drywall compound go bad?
Drywall compounds containing water-based organic ingredients tend to go bad in the presence of moisture contamination or too high or low temperature fluctuations. Even due to a lack of effective preservation after opening, it can go bad. But normally it lasts up to nine months after opening.
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Drywall has a 12-month shelf life if it has not been opened. It actually contains water-based organic ingredients that can easily go bad. However, it also depends on a variety of factors like humidity, air, temperature fluctuations, and the storage method why it goes bad.
It normally lasts up to nine months after opening, but if opened sooner, it might go bad, emitting a terrible odor, accumulating black fungus, or converting its off-white color into gray or brown discolorations. Here the factors briefly discussing:
Lack of preservation:
If drywall compound is not kept in an airtight or waterproof container, it may decompose. Because drywall compound contains water, it is easily spored by mold when exposed to humid air, especially on rainy days. Molds love moisture.
Temperatures that are too low or too high:
Drywall chemicals should be stored at temperatures ranging from 32 to 35 degrees Celsius. As the temperature drops below 13 degrees Celsius, the chemicals begin to freeze and clump together, especially at 0 degrees Celsius.
On the other hand, too much heat causes the drywall compounds to dry up, giving cracks. Therefore, the ideal temperature for storage and avoiding decomposition should be found.
Humidity:
Humidity levels of more than 40% in the air have an unfavorable effect on drywall compounds, resulting in an unpleasant odor and black mold stains all over.
The problem of drywall compounds going bad can be solved by keeping them at a humidity level of 20% to 40% in a room temperature setting.
Does drywall have a shelf life?
Yes, drywall has an expiration date. Most brands have a recommended shelf life of 12 months from the date of manufacture, after which the quality of the product may deteriorate. However, with appropriate handling, it can be kept for many years.
Within a nine-month to one-year shelf life, the wet compounds are suitable for application. However, with careful storage, dry compounds can readily last a year.
The shelf life of drywall compounds is unpredictable since it is affected by a variety of elements like humidity, air, temperature, and the storage method.
When a compound reaches the end of its shelf life, it tends to dry up, losing its strength and efficacy and becoming contaminated by mold. Therefore, it’s best to utilize it before it expires.
Does drywall mud go bad if it freezes?
Yes, if the drywall mud freezes, it will clump and crystallize. The drywall has a water-base complex formula that contains water and has the same freezing point as water, so if it is exposed to cold temperatures, it will freeze and go bad, leading to a poor application.
For best results, store drywall mud at a typical room temperature of 65 to 85 degrees Fahrenheit; otherwise, the drywall mud will go bad.
Normally, drywall mud can freeze at temperatures below thirteen degrees Celsius. However, any deviation from the regular room temperature can cause the drywall mud to deteriorate. If used below 0 degrees Celsius, the drywall mud may split and clump.
Previously frozen mud may emit a foul odor after a few days, and it may also shatter over time. If the texture freezes, it will never be the same and will dry hard, resulting in poor performance when used.
How do you know if drywall mud is bad?
When drywall mud deteriorates, it displays indications such as black mold spots on the surface, as well as discoloration, foul odors, and dryness caused by the decomposition of its organic contents.
Moisture, temperature, and the location of the storage procedure all tend to contaminate the drywall mud and cause it to deteriorate. Here are the symptoms by observing you may know if your drywall mud is bad:
Moldy spots:
When drywall muds aren’t stored in an airtight container, mold in the air has a chance to grow. Because drywall mud is water-based, molds that come into contact with it spread quickly, resulting in black moldy spots.
These black patches indicate how much of the surface has been affected by mold spores.
An unpleasant odor:
Drywall muds have a pleasant, light, chalky aroma to them. When it becomes stale, it emits an unpleasant odor that has been described as being like rotten eggs.
Discoloration:
When mold causes discoloration, it will reveal certain regions of brown, gray, or black discoloration. In most cases, drywall should be kept at a humidity level of 20 to 40%. Anything higher than that will encourage mold growth.
Drying out:
Due to the drying out of the chemical compounds, it loses its strength and potency and as a result, the drywall mud will reveal cracks and peel off. It happens most of the time because of temperature fluctuations.
How long can you keep drywall compound once opened?
The self life of drywall compound typically is considered 12 months or one year. And there’s no method that can make them last forever because of its many different formulations.
But after opening, the drywall mud won’t even survive more than 9 months or it can go bad even sooner. Moreover, you have to store that very carefully to reuse it.
It’s wise not to buy too much extra mud as it’s going to eventually expire. However, it must be stored in an airtight and waterproof container to extend its shelf life, keeping in mind that it should not be exposed to direct sunlight or water.
Or, it will go bad and accumulate fungus and mold. It may emit a terrible smell and become discolor, gray or brown.
How to keep drywall mud good for long?
If the drywall mud is stored properly, it can be reused for a long time. But it’s true that there’s no method that can make them last forever and so, it’s better not to buy too much extra mud. However, here are the ideas you can follow to keep drywall mud good for reusing a long time:
Store the mixture in an Airtight container:
The container where you’re going to store the drywall compound has to be completely airtight. If it’s pre mixed use a bucket and make sure the lid is locked in place before the mix is stored.
Cover with bleach rag:
The bleach rag helps by terminating any elements which can cause the drywall mud to become damaged and unusable. Dip a clean rag into a mixture of two parts water and one part bleach and place it in a single layer on top of the tight plastic covering.
Avoid storing in hot or freezing:
When picking a place to store, it’s better to use moist Locations and avoid warm, humid spaces as it may affect the dry compounds. Though freezing is not a good option to store the mixture, it can be used in the warmer months for storing.
However, during winters it shouldn’t freeze because it’ll dry the mud.
Can I use old drywall compound?
Old drywall compound can only be used if the proper storage methods were used as the drywall compound package is exposed to a number of contaminants.
Even If the compounds are wet or premixed it can also be used around nine months to a year only if they are kept in the right condition. Otherwise, microorganisms may infiltrate the compound or it may dry out.
According to the experts, it’s suggested to use the opened package or mixed compound within three months from opening to get the best result.
Otherwise, it may start to lose its strength and potency and also may dry out, become moldy or otherwise become unusable over time and even become risky to use. It’s actually better not to buy too much at a time as it eventually will go bad within a short period.
Final Thoughts
Because of the presence of moisture contamination or temperature fluctuations or lack of effective preservation in its organic ingredients, drywall compound can go bad. Though, the self life of drywall compound is typically 12 months, without storing carefully it may go bad more quickly.