THREE STEPS TO SELECTING THE RIGHT LADDER

Choosing the right ladder for the task at hand starts with identifying the job you will be using it for. If the job is a free-standing task, then a stepladder is likely the right tool. If using it for elevated tasks where you must lean the ladder to get access, then an extension ladder is the better choice. Remember to never lean a stepladder against a building and use it like you would an extension ladder.

Whatever the task, follow these three steps to ensure your product selection will not underperform.
 

1). Choose the right height and reach

Note that stepladder labels include the height of the ladder when open. In this table, the user’s maximum reach is calculated for an average person’s height of 5’9” with a vertical reach of 12 inches.

Tip: If you know how high you want to reach, let’s say 10 feet, you would likely select a 6-foot stepladder allowing you to safely stand almost 4 feet above the ground.

STEPLADDERS
LADDER SIZE APPROX. HIGHEST STANDING LEVEL MAXIMUM REACH
4’ 1’11” 8’6”
5’ 2’10” 9’5”
6’ 3’9” 10’4”
7’ 4’9” 11’4”
8’ 5’8” 12’3”
10’ 7’7” 14’2”
12’ 9’6” 16’1”
14’ 11’5” 18’
16’ 13’4” 19’11”
18’ 15’3” 21’10”
20’ 17’2” 23’8”

Extension ladders have a few other considerations. Here, the maximum working ladder length and highest standing level come into play for an average person’s height of 5’9” with a vertical reach of 12 inches.

EXTENSION LADDERS
LADDER SIZE MAXIMUM EXTENDED LENGTH MAXIMUM REACH WORKING RANGE TO TOP SUPPORT MAXIMUM ACCESSIBLE ROOF HEIGHT RANGE
16’ 13’ 15’11” 7 ½’ – 12 ½’ 4 ½’ – 9 ½’
20’ 17’ 19’10” 9 ½’ – 16 ½’ 6 ½’ – 13 ½’
24’ 21’ 23’8” 11 ½’ – 20’ 8 ½’ – 17’
28’ 25’ 27’7” 13 ½’ – 24’ 10 ½’ – 21’
32’ 29’ 31’5” 15 ½’ – 28’ 12 ½’ – 25’
36’ 32’ 34’4” 17 ½’ – 31’ 14’ – 28’
40’ 35’ 37’3” 19’ – 33 ½’ 16’ – 30 ½’
44’ 39’ 41’1” 21’ – 37 ½’ 18’ – 34 ½’
48’ 43’ 45’ 23’ – 41 ½’ 20’ – 38 ½’
60’ 48’ 49’10” 23’ – 46 ½’ 20’ – 43 ½’

 

2). Choose the right weight capacity

When selecting a ladder know its duty rating, the category assigned to a ladder to easily know how much total weight a ladder can support on each of its steps without any risk for the user. It’s written in Roman numerals going from lighter loads to heavier ones. Lighter loads start at duty rating of III and go to a duty rating of I for heavier loads; then adding IA and IAA for even heavier loads.

Remember that these ratings include all the weight a ladder can support. When thinking about the total weight that will be on the ladder, consider the weight of your tools and materials as well as your body weight.


TYPE IAA
375 LBS. LOAD CAPACITY (includes weight of user plus materials)
Professional use.  Extra heavy duty.
Uses:  MRO and industrial construction

TYPE IA
300 LBS. LOAD CAPACITY (includes weight of user plus materials)
Professional use.  Extra heavy duty. 
Uses:  Roofing, building maintenance, contracting and industrial construction

TYPE I
250 LBS. LOAD CAPACITY (includes weight of user plus materials)
Industrial use.  Heavy duty.
Uses:  Building maintenance, general contracting and sheetrock
 

3). Choose the right material

Step and extension ladders are made with two main types of material: aluminum and fiberglass. Both materials have advantages and disadvantages, depending on the type of job you have planned.

Aluminum ladder advantages

  • Light weight
  • Long-lasting construction
  • Resist corrosion
  • Ideal for painting, roofing and siding
  • Disadvantage: Can be dangerous to use near electricity as they are conductive, and doing so may cause electrical accidents

Fiberglass ladder advantages

  • Strong and durable
  • Weather-resistant
  • Ideal for heavy-duty construction
  • Safe for working around electricity, provided they are clean and dry