Rule of thumb: your ladder's extended height should be about 3–4 feet more than the highest point you need to reach, so you never stand on the top rungs.
- Bulbs, ceiling fans (9–10 ft ceilings): 10–12 ft
- Painting, high windows: 14–16 ft
- Exterior work, double-height ceilings, terraces: 18–23 ft
A telescopic ladder extending to 23.6 ft covers nearly every household task. Never stand on the top rung; size up rather than overreach.