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The four-to-one ladder ruleAn extension ladder leans on a wall. For every four feet of height up to where the ladder touches the wall, the base sits one foot out from the wall. The ladder reaches three feet above the roof edge so there is something to hold when stepping on and off.Roof edge4 up1 out3 feet above the edgeThree points of contact,belt buckle between the rails
Four up, one out: for every four feet of height, the foot of the ladder sits one foot from the wall. Extend it three feet above the roof edge.

How to do it

  1. Inspect the ladder for cracked rails, loose rungs and missing feet, and check its load rating covers you plus tools.
  2. Look up and keep the whole ladder at least ten feet from overhead power lines.
  3. Set the feet on firm, level ground, using a ladder leveler rather than bricks on uneven ground.
  4. For an extension ladder, place the base one foot out from the wall for every four feet up to where it rests.
  5. Extend it at least three feet above a roof edge or landing so you have something to hold as you step off.
  6. For a stepladder, open it fully and lock the spreaders; never lean a folded stepladder against a wall.
  7. Climb facing the ladder, holding on with both hands, and carry tools on a belt or haul them up on a line.
  8. Keep your belt buckle between the rails, move the ladder instead of leaning out, and stay off the top two rungs of an extension ladder and the top cap of a stepladder.

Stop and call a professional if

  • The job is on a roof, a second-story gutter, or anything you cannot reach with your feet well below the top rungs.
  • The ground is soft, sloped or icy.
  • There are power lines anywhere near where the ladder would go.

Common mistakes

  • Setting the ladder too steep or too shallow instead of using the four-to-one rule.
  • Overreaching to the side to save climbing down.
  • Using a metal ladder near power lines.
  • Standing on the top of a stepladder or its paint shelf.
  • Climbing alone with nobody home to help if you fall.

Quick self-check

Three questions. Your last score is kept in this browser.

1. An extension ladder reaches a wall 16 feet up. How far out does the base go?
2. How far should the ladder extend above a roof edge?
3. Where should your belt buckle stay?

Teach this to someone

A one-page sheet for showing a friend, a roommate or a kid: what to say, what to show, and one question to check it landed.

Sources

  • Ladder maker's safety labels and instructions, per ladder. Checked September 28, 2026.

Last reviewed . First published .