# IMO primer shrinks drywall mud



## omax514 (Oct 17, 2021)

I am a DIYer. I drywalled and mudded my whole place, learning as I went with pretty good results. However, I've come to realize that drywall mud shrinks once primer is applied. Everything looks perfect shining a light sideways on my walls before primer. After I prime, I see the screws. Every single one in harsh lighting. This is after 3, sometimes 4 coats if I feel some are still not perfect. I've used SICO go prime, and KILZ 3. For drywall mud I use CGC all purpose light. Is there such thing as a primer that doesn't react this way with drywall mud? 

Here is a picture of a screw before and after primer.


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## hendrix417 (Aug 9, 2018)

how many coats of mud on screw?


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## Loffredo (Jul 22, 2021)

is the first coat proud of the patch before skim coating? Also, try pushing the board to see if the screw is popped, the drywall could be moving. Sometimes you need to add additional screws on both sides of the pop.


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## picks drywall (Apr 13, 2021)

1st pic looks like someone sanded the life out of the board and fuzzed paper? sand paint and roll again. second pic "nail pop like said. when you rolled or sanded it pushed rock tight and popped. non professional mistakes = reason its called "skilled trade".


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## Shelwyn (Apr 10, 2015)

Hey you made a lot of mistakes but you saved yourself a lot of money haha.


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## Michael T. Pendarvis (Nov 3, 2021)

How do you keep drywall mud from shrinking?


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## Shelwyn (Apr 10, 2015)

Michael T. Pendarvis said:


> How do you keep drywall mud from shrinking?


The drywall mud has to dry completely between coats, which happens via different processes depending on the type of compound used. In the most common ready mixed joint compound, as the water evaporates from the compound, the solid particles left behind take up less space, causing the compound over the area as a whole to shrink.


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## epalacios_317 (Nov 6, 2021)

Mate I would also suggest checking the humidity of the drywall. I have had this issue even after applying 3 coats of mud. If gypcrete is being poured or you have excessive humidity before joint compound has time to cure properly you will have shrinkage. The best way to check is by going to your local hardware store and picking up a humidity prong gadget its very inexpensive we are talking 40 bucks or so. Just plug into your drywall and let it check the humidity make sure you are definitely no more then 15-17 percent.


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