Project Difficulty:
Easy Estimated
Project Time: A few minutes to set up
Tools and Materials:
Two heavy-duty extension ladders
Set of ladder jacks
Scaffold plank
Ladder jacks are part of a ladder-jack scaffold system in which the jacks are attached to a set of ladders and then a scaffolding plank is positioned to rest on the ladder jacks. This type of simple scaffolding is useful for when you are working in one area for an extended period of time, or on an area that you cannot get a single ladder exactly where you need it (such as dead center on an upstairs window). It is meant to provide support for no more than two people working no more than 20 feet above the ground. Two people are needed to set up the system; each person climbs a ladder, holding an end of the plank. Once the plank is in place, you do not need the helper again until it is time to take the scaffolding down.
Ladder-jack scaffolding equipment is available at home center stores and rental stores. Always use a proper plank, which is typically aluminum and 10 feet long. Each end of a plank should extend 12 inches beyond jack; the ladders should be placed so that the jacks are no more than 8 feet apart. Resist any urges to press scrap lumber into service as a scaffolding plank. Jacks are adjustable to fit the width of the plank. Read and follow the instructions and cautions that accompany the jacks and possibly other components of a system.
Using scaffolding can make a job easier. Working while standing on the scaffolding, however, requires concentration so that you do not forget that you're standing on a narrow (about 18-inch-wide) platform. Inexperienced people have been known to get comfortable moving from side to side and front to back, so much so that they forget where they are, and take an unfortunate step off the scaffolding.
1.
Set Up the Ladder Jacks
Set two ladders in position for the jacks so that when the plank is in position each of its ends will extend 1 foot beyond a jack. If using a 10-foot long plank this means setting the ladders about 8 feet apart. Check that each ladder is level and stable. Working one ladder at a time, carry up a ladder jack and, at the desired height, secure the jack properly to the rung (Fig. 1). Make sure that both jacks are set to an equal height. Refer to the instructions that accompany the jacks for specific information.
2.
Bring Up First End of Plank
Carry one end of the plank up one of the ladders while a helper remains on the ground supporting the other end of the plank. (Fig. 2)
3.
Bring Up Second End of Plank
Rest the first end of the plank on the ladder jack and hold it in place while the helper brings up the second end. The first end juts over the jack as the second end comes up. (Fig. 3)
4.
Secure the Plank
Flip the plank into position onto the jacks. Make sure it is securely held by the jacks and extends at least 12 inches over at each end. (Fig. 4)
