Most homes need two kinds of ladders: a stepladder for heights up to 10 feet and an extension ladder for greater heights.
Make sure a stepladder has grooved treads, rubber or plastic non-slip safety shoes, and angled metal braces on the lowest tread. On an extension ladder look for a reinforced bottom rung as well as pivoting non-slip safety shoes and a device that locks the two sections together firmly.
If a ladder's rungs or steps aren't skid resistant, buy adhesive-backed anti-slip strips from a hardware store and apply them.
Ladders are available in wood, aluminum or fiberglass--the last being the costliest but the safest. (Fiberglass protects against accidental electrical shock.)
Buy a ladder that's rated Type I (heavy duty--each rung is capable of supporting 250 pounds) or Type II (medium duty--225 pounds per rung). Or for 300-pound support, buy Industrial IA.
Here are some tips for the safe use of ladders:
When moving a ladder, avoid overhead wires. A metal or wet wood ladder that touches a power line can give a lethal shock. When on a metal ladder, use grounded double-insulated power tools only.
Position an extension ladder so that the distance between its base and the wall is one-quarter of the ladder's length up to its point of support. Don't lean a ladder against a window or a door.
When you open an extension ladder, make sure that there's at least three feet of overlap. Set the rung locks.
To raise an extension ladder, stand the ladder against the wall and lift the top end, rung by rung to the desired length, at least three feet above working level.
When climbing up or down, face the ladder and hold on with at least one hand. Haul tools up in a bucket after you are set, or carry them on a tool belt.
Make sure your hips stay within the side rails. Many falls from a ladder are caused by overreaching. Don't lean out. Move the ladder instead.
Open a stepladder fully, and fully lock the braces.
Before climbing an extension ladder, jump up and down lightly on the bottom rung to ensure rungs are firmly planted.
On muddy ground, drive a 2-by-4 stake into the ground behind the extension ladder. Then tie a rope around the second rung from the bottom and secure it to the stake.
When working high on a ladder against the house, lash the ladder through an open window so that it can't fall over. Tie one end of a rope to a rung, about two-thirds of the way up, and the other end to a radiator or other solid object inside. Or tie the rope to a 2-by-4 long enough to bridge the inside of the window. Pad the 2-by-4 to avoid marring the interior window frame.
Wall grips on ladder tops prevent slipping, and ladder-leg extensions can compensate for uneven ground. Or, on uneven ground, put a firm, flat block under a ladder's lower foot. On soft ground, place a wide board under both ladder feet.
Don't lean a ladder on an aluminum or vinyl gutter. Use a tall stepladder. Or add a U-shaped stabilizer to your extension ladder to hold it out from the wall.