sheetrock mud

[chrisasst]

If I am putting up molding, do I need to mud the joint between the wall and the ceiling?

 

[gzecc]

Technically yes as per fire code.

 

[billb3]

I would, just to stop the dust and dirt from filtering down through the joint.
It's also one more wind penetration possibility.
If you're covering the corner with molding you wouldn't have to finish / sand it.

 

[firefighterjake]

Another vote to do it . . . for the noise/wind/fire protection and in case you ever decide to take down the molding . . . but as billb mentioned you don't necessarily have to sand it and make it pretty.

 

[woodsmaster]

I would Paper tape it but not finish it. It will seal the house better.

 

[gpcollen1]

Tape and mud provide and air seal to prevent drafts...it is a must do, even if you don't sand it.

 

[btuser]

The finished joint actually makes the two sheets bond together, so movement is limited which is important if you've got molding that is crossing two planes (like crown). Plus, its an opportunity for you to make your molding install go smoother. You can even out the wall with compound so you don't have such large gaps in between the wall board and the molding. Of course, this should have been done prior to sheetrocking but you get a second chance here.