Cabin that is completely sheetrocked inside…heat on when occupied…temps from -20 to +85. Some joints are cracking due to the temp variances. Is there a paint I can apply to help hide this and prevent future visible cracks? Annually touching up of the cracks is not an answer.

I was priming walls that were previously painted to cover up some kids marks and after finishing I discovered the primer was oil based. I feel like the prior paint was latex. Do I need to sand the primed areas before painting the wall with latex?

Primed some interior walls but haven’t had a chance to paint them. Is there a time period the primed walls must be painted? Someone told me one must paint primed walls within one week of priming them.