How do I know when a ladder should be thrown away?

A ladder does not wear out gradually in a way you can watch. It develops a specific defect at a specific point and then fails there. That means the useful skill is not judging general condition but knowing the short list of faults that mean the ladder is finished, and checking for them habitually.

Safety

Step by step

1. Check it before every use, not annually.Thirty seconds, walking the length of it. Most ladder damage happens between uses — being run over, falling off a roof rack, being leaned on by something heavy — so the check that matters is the one immediately before you climb.
2. Sight along both stiles.Lay the ladder flat and look along each stile from the end. Bends, kinks and twists are far easier to see this way than from the side, and any of them condemns it. An aluminium stile that has been dented has lost strength that cannot be restored.
3. Twist and pull each rung.A rung that turns, moves, clicks or shows a gap at the stile has a failed joint. Rungs are usually swaged or riveted into the stile and a failed joint is not repairable.
4. Check the feet.Missing or perished feet are the most common condemning fault and by far the most common cause of a base slipping. Replacement feet are available for many ladders and fitting genuine ones is a legitimate repair; running without them is not.
5. Work every locking mechanism.Extension locks, hinge locks, spreader locks, stabiliser clamps. Each should engage positively and hold. A lock that only engages on one side, or that has to be persuaded, is finished.
6. Look for evidence of an event.Scuffed paint on a stile, a bent stabiliser, a distorted foot, a rung with a flat spot. A ladder that has been dropped from height or driven over may look serviceable and be structurally compromised.
7. Reject repairs.Welded aluminium stiles, riveted patches, replacement rungs made from something else, a splint on a timber stile — none of these restore the tested strength and all of them are found in accident reports. Feet and ropes are the only routine replaceable parts.
8. Never paint a timber ladder.Paint hides splits and rot, which is exactly what you are inspecting for. Timber ladders are treated with clear preservative for this reason.
9. Destroy a condemned ladder.Cut it up, or at minimum remove the feet and mark it clearly, before it goes for disposal. A ladder leaning in a garage marked 'do not use' will be used.
10. Store it so it stays serviceable.Horizontal, supported at several points along its length, off the ground, out of the weather, and where it cannot be knocked or leaned on. Hanging on two brackets in a garage is ideal; standing on end in a corner bends it, and leaving it against a fence outdoors invites both corrosion and theft.

Tips

• Ladders are among the most stolen items from gardens and garages. Store yours out of sight, and consider a ladder lock or a ground anchor — a stolen ladder is also somebody else's way into a first floor window.
• Timber ladders left outdoors rot from the inside at the rung joints where water sits. Age alone is not a fault; weathering is.
• Keep the manufacturer's label legible. If it has gone, so has your evidence of the rating, and a ladder with an unknown rating should be treated as the lowest.
• If a ladder has been in a fire, or exposed to strong chemicals or acids, scrap it regardless of appearance. Aluminium loses strength invisibly.

Checklist

• Stiles: no bends, dents, splits, kinks, corrosion or repairs
• Rungs: all present, tight, straight, uncracked, not spinning in the stile
• Rung-to-stile joints: no movement, no cracked or missing rivets, no gaps
• Feet: present on both stiles, not worn smooth, not perished, not missing
• Extension locks: engage fully and positively on both sides at every setting
• Rope and pulley: not frayed, running freely, correctly reeved
• Spreader bars and hinges on a stepladder: straight, locking, undamaged
• Steps and platform: secure, clean, no paint or grease
• Label: present and legible, with the rating and standard readable
• Overall: no twist when laid on flat ground, no sign of a heavy impact

Questions people ask