Damp plaster does dry out, although the drying time depends on several factors, including the type of plaster, the surrounding temperature, moisture content, and the extent of the dampness. Sometimes, it can take weeks or months for wall plaster to dry naturally.

The time it takes for thinset to dry is determined by your room’s ambient temperature and humidity levels. Assuming the average humidity level is around 40% with an average temperature of 70 degrees Fahrenheit, thinset can dry within 48 hours. Lower temperatures and higher humidity can extend the curing process beyond 72 hours, while high heat and zero humidity can shorten the curing process. However, thinset can crack if it dries too fast.

If your home’s foundation shifts slightly over time, any seams in the drywall represent the weakest point in the wall, leading to cracks. If your home has significant changes in temperature and humidity, this can cause the drywall to swell and contract slightly, causing a crack at the weak point of the seam. If your drywall installer did a poor job securing the panels to the wall studs, this could cause a weak layout and cracks in the seams.

Furring strips, thin strips of wood or metal, are not always required for ceiling drywall installation. If the ceiling surface is even and in good condition, drywall can be directly attached to the ceiling joists using screws. However, furring strips become essential when dealing with irregular surfaces or when additional insulation or soundproofing is needed. They create a level substrate for attaching the drywall. Ultimately, the decision to use furring strips depends on the condition of the existing ceiling and the specific requirements of the project.