An access panel or plumbing access door is a door, panel or piece of plywood that can be easily removed to provide access to a shut-off valve, drain or other (most often) plumbing part.
DIY Dictionary: Access Panel
What is an Access Panel?
An access panel is a door, panel or piece of plywood that can be easily removed to provide access to a shut-off valve, drain or other (most often) plumbing part to which you need occasional access in order to make a repair. It can also be called a plumbing access door. Learn how to install a shower faucet and plumbing access panel. Perhaps the most common place you’ll encounter an access panel is on the back side of the plumbing wall of a bathtub or shower. Learn how to fix a leaking shower faucet.
Though a piece of plywood will usually suffice for an access panel, you can purchase a manufactured plumbing access panel, complete with a frame and removable door, for about the price of a takeout pizza. Installing one involves cutting the appropriate size hole in the drywall, then gluing the access panel frame in place. Increasingly, access panels are being installed to provide easier access to low-voltage and communication wiring systems and devices. Some sneaky people use access panels as a place to stash valuables. Check out our ultimate guide to secret hiding places in your home.