What is a rough opening?
A standard US rough opening consists of:
One of the fundamental elements here is a wall stud.
Studs are traditionally made of wood, usually 2"×4" or 2"×6" dimensional lumber and typically placed 16 inches (406 mm) from each other's center, but sometimes also at 12 inches (305 mm) or 24 inches (610 mm). The wood needs to be dry when used otherwise problems may occur as the studs shrink and twist when they dry out.
Considering this fact, the actual sizes of the framing studs are:
The standard 2"×4" or 2"×6" wall assembly is as follows:
Studs with insulation filling in between and a layer of drywall from both sides of the construction. The drywall is normally 5/8’’ thick. Sometimes several layers of drywall are used. This knowledge is important whenever you want to measure the thickness of the wall because it actually defines whether you need an extension or not.
