How ladder length planning works
Support height + 3 ft, class matching, and climb safety.
Ladder length planning
Telescoping ladder size by support height
Enter height to the top support or landing in feet. Get a 13 / 17 / 20.5 ft class or NO_MATCH. Adds 3 ft above landing for straight-extension shopping. Confirm load rating and never stand on top steps.
Ladder length planning
Result
Needed ≈ support_height_ft + 3. Classes: 13 · 17 · 20.5 ft max straight length. Above 20.5 → NO_MATCH. Straight-extension shopping screen (OSHA-style +3 ft), not a full job-site fall-protection plan.
From measurement to decision
Open the full calculator
Same tool with room for examples.
13 vs 17 vs 20.5 ft classes
When each class fits — and when none do.
No resources match. Try another term.