Square, Level and Plumb

Think builders have a language all their own? Add these terms to your vocabulary, and you'll be in the know. Level refers to a being straight on the horizontal. Plumb refers to a straight vertical line. Square refers to the intersection of two lines to create a right angle.

How to Use a Laser Level

Laser levels are easy to use, and with a variety of designs available, there's a style that suits any application. Different types of laser levels have been developed for specific uses, but all laser levels include two common components: the laser plus a leveling base that can sit on the floor, mount on the wall or attach to a tripod. This base helps you to project the light at the required height. There's also a leveling mechanism, either a bubble vial or a pendulum and magnets plus electronic sensors (the differences between these two types of mechanisms will be discussed below). The enclosure, or case, is usually made of a durable plastic or metal that's tough enough for sturdy performance on a job site.

Laser levels find "level" in different ways. Manual laser levels work in the traditional way: The user lines up a bubble inside a vial either by repositioning the level or turning a knob. Well-suited for typical do-it-yourself projects, these laser levels are less expensive and require less battery power than a self-leveling unit.

Self-leveling units offer a greater degree of accuracy. They work best when placed on a surface that the user determines is "close to level." You can use a bubble vial to manually level the unit before the unit's self-leveling mechanism takes over. The laser component hangs like a pendulum inside the level. Magnets and gravity work together to still the pendulum, and the beam is then projected through a light or prism.

Some laser levels are equipped with electronic self-leveling sensors that boost accuracy and reliability, and they are ideal on a busy outdoor construction sight. For indoor jobs where the level is moved around frequently, a self-leveling mechanism helps to save time and increase reliability.