Patching and Plastering - old joint compound

i have a bucket of joint compound that's 1 1/2 years old. it used to be white, but now it's grey and smelly. i'm playing it safe and going to buy a new bucket. but just out of curiosity, how long can you keep this stuff if it's sealed well, and how do you know when it's gone bad?

i bought the same brand as the old bucket and can see and smell the difference. old bucket is runny, grey and smells like low tide. new batch is thick and creamy and doesn't stink. but I'm still curious about how long this stuff keeps. Bucket tells retailers to rotate stock every 90 days. But I also heard not to hang onto it for more than a month. I've got a few projects I'll be doing over the next few months. Not sure if it's best to buy a small jug of compound for each project or a big bucket to get me through them all.

The better you seal the bucket, the longer it will last. I often add a little water to cover the mud - this will help it to last longer. Basically joint compound will last forever or until it dries out [even then, mixing in water will resurect it]

If the j/c becomes moldy/stinky it is best to trow it out and get a new bucket - it's not that expensive and you don't want to introduce mold to your walls/ceiling :eek:

I know this doesn't exactly give you a definete answer as to how long a bucket will last but it just depends on how well it is sealed. I once opened an unopened bucket that I had bought close to a year earlier and it was still good :D but I've also had buckets in the van for only a month or so that were getting kind of iffy.

I'll use the water trick. One or two big buckets should get me through all of my projects, and as long as I can get them to last a few months, I should be set. That will save me a few bucks. The big buckets are less than $10, The small buckets, which hold less than 1/8 the big bucket, are more than $5. So buying in bulk will help me keep the costs, which seem to add up fast, down at least a little bit. thanks again for the help.

I think throwing a layer of plastic wrap across the top of the bucket before you put the lid on makes a better seal.

Jointing compounds, won't last more than 6 months after opening.

Like others have said it gets mouldy and very smelly.

To store:

Clean the sides inside of the bucket with a wet sponge.
Pour about 2" of water over the top.
Make sure the bucket is well sealed.

When you go to use it again tip off the water.

Sometimes the top layer will still go a bit hard. If so take off the top inch or so, give it a good mix and it will be good to go.

If it smells chuck it out.

Cheers