Learn about Ladders

The three basic types of ladders are straight (extension), step and step/extension. Stepladders include step-stools and platform ladders, generally for home or light commercial use.

Quality classifications of step/extension ladders include consumer (household), commercial (mechanic) and industrial grades.

Metal ladders, usually made of aluminum, require little if any maintenance. Wood ladders should be treated with two coats of clear penetrating sealer or varnish. Opaque sealers should never be used on wood ladders because they hide cracks or other defects.

Hinges and other moving hardware should be lubricated periodically. If the metal is not rustproof, it should be treated periodically with clear varnish or other rust proofing material.

Ladder rungs are either flat, round or “D” shaped. Stepladders use 3″ or greater channels for flat steps. “D” rungs are preferred for step/extension and straight ladders. Their flat top surface is more comfortable to stand on.

Rungs must be capable of carrying an 800-LB. load as a household ladder, a 900-LB. load as a commercial ladder, and a 1,000-LB. load as an industrial ladder. The minimum size considered acceptable for round rungs is 1-1/4 and 1-1/2 the minimum for “D” rungs.

Standards established by the American National Standards Institute (ANSI) and required for ladder identification are:

  • Type I, industrial, duty rated at 250 lbs. For tradesmen, construction, maintenance and industrial.
  • Type IA, extra-heavy-duty industrial, duty rated at 300 lbs. For industrial use.
  • Type II, commercial, duty rated at 225 lbs. For handymen, light maintenance, light mechanics.
  • Type III, duty rated at 200 lbs. For household use.

All ladders should bear labels with ratings, sizes and maximum standing heights.


There are four major points to consider when selecting a ladder: the kind of activity involved, the demands of the application, the height of the ladder must reach so the climber may work from a safe position, and the basic material from which the ladder is made.

Activity: In most cases, the activity involved will make the choice fairly obvious. For example, a stepladder would be the choice to paint the outside walls and ceilings; an extension ladder usually is needed to paint outside. If the job involves more effort than usual, or will require more time on the ladder, consider “upgrading” to a ore-efficient or capable design. For example, a platform ladder in place of a stepladder.

Application: Ladders are constructed to safely hold a certain amount of weight, which includes the user, clothing and tools. Therefore, ladders are matched or job rated to the physical demands and abuse of the application. For example, a ladder used daily on a construction site should feature more-sturdy construction (or higher-duty ranking) than the ladder used a few times a year for light chores around the house.

The heavier-duty ladder, while it costs more to build and buy, is better suited for commercial or industrial use, because it will stand up under more frequent and rigorous use. The homeowner may prefer a lighter and more economical “household”-duty ladder for less-frequent use and less-demanding application.

Because the most critical point involved here is the rated-load capacity, or the working weight of the user, his clothing and tools, the duty rating is described in terms of pounds.

Household-rated ladders are economical, lightweight and dependable for around-the-house use. They represent an excellent value. Commercial-rated ladders are engineered for the handyman, painter, mechanic and for general use. Industrial-rated ladders are for the heavy climber, for daily use. Stable, strong and built to take it, industrial ladders are intended for contractors, maintenance and industrial work.

Every ladder’s duty rating is prominently displayed by a color-coded label on the ladder side rail. Look for the proper duty ratings to match the highest level of use.

Height: Beyond the actual ladder height, the height of the maximum safe working position on the ladder must be considered. With stepladders the ladder should be high enough so the user does not stand above the second step from the top. The first step from the top carries a label warning the user not to stand on that step. With extension ladders, the user should stand no more than four rungs from the top.


The final consideration is which ladder material is best suited to your needs. The three most common and generally available materials for ladders are wood, aluminum and fiberglass. Each has certain characteristics that make it the preferred material for certain uses.


Because clean and dry wood ladders are nonconductive, they offer a margin of safety when working near electricity. They also offer a natural firm grip for the worker’s feet and hands. However, wood ladders are heavy. A pleasing traditional look, wide availability and outstanding economy are among wood ladders’ strongest attributes.


Aluminum’s strongest advantage is its light weight in combination with strength. Aluminum is also corrosion resistant, economical and performance is reliable. However, because aluminum ladders conduct electricity, they should never be used when working near energized electrical lines.


Fiberglass offers a favorable blend of desirable characteristics when compared with wood or aluminum. Being nonconductive (like dry, clean wood), yet made of modern and rugged materials (like aluminum), fiberglass ladders have become a leading choice for applications where they must be used regularly in widely varying circumstances.

The Proper Paint for the Job
– Alkyd primer needed on new wood. Two- or three-day wait recommended before any oil-base paint is applied after rain. Not recommended for application over masonry. Requires 12 to 48 hours to dry, depending on local conditions. Brushes and tools clean with turpentine.
– Need alkyd or good latex primers on new wood. Have chemical binder instead of oil. Resistant to moisture. Dry to touch in 30 minutes (under normal conditions). Brushes and rollers wash in water.
– Need latex primer on new surfaces. Should be applied in heavy layers. Takes 4 to 12 hours to dry. Brushes and rollers wash in water.
– Latex paints are waterbased; alkyd paint, oil-base. Waterbase paints dry faster than oil, and, as a rule, do not give off “painty” odors common to oil quality alkyd paints form a tough non-porous surface which makes them more washable than latex. Latex is easier to use because clean-up is done with water.
– Require undercoat and surface preparation. Go on like paint, but look like porcelain after they dry. Used on ceramic tile, walls, bowls and appliances. Will not stick if applied over ordinary paint. Toughest finish available.

Check your state and local codes before starting any project. Follow all safety precautions. Information in this document has been furnished by the North American Retail Hardware Association (NRHA) and associated contributors. Every effort has been made to ensure accuracy and safety. Neither NRHA, any contributor nor the retailer can be held responsible for damages or injuries resulting from the use of the information in this document.

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