What is the minimum distance a 40' extension ladder should be set from the wall it is leaning against?

To determine the minimum distance that a 40' extension ladder should be set from the wall it is leaning against, it's important to consider the proper ladder angle for safety and stability. The typical recommendation is to place the base of the ladder one foot away from the wall for every four feet of ladder height.

For a 40-foot ladder, this rule indicates that the base should be positioned 10 feet away from the wall. This set-up helps ensure that the ladder is at a safe angle, which typically ranges from about 75 to 80 degrees to the ground. Having the ladder too close to the wall can lead to instability and increase the risk of the ladder tipping over.

Choosing a distance of 10 feet aligns with this safety guideline, meaning that 10 feet is the minimum safe distance from the wall when using a 40-foot extension ladder.