FactSheet

Ladder Jack Scaffolds

Supported Scaffolds

A ladder jack scaffold is a system designed to perform activities, such as: installing 

building exteriors, trim, and finishes. Contractors widely use ladder jack scaffolds 

because of their cost effectiveness, portability, and quick erection and dismantling 

procedures, as well as their adaptability for use in narrow spaces at construction 

worksites. 

What is a Ladder Jack Scaffold?

Triangle-shaped brackets called “ladder jacks” 

are attached to portable ladders, which are used 

on each side of a ladder jack scaffold to form a 

means of support for a platform.

Ladder Jack Scaffold

Photo courtesy of National Association of Home Builders.

Types of Ladder Jack Bracket Devices

There are different types of Ladder Jack bracket 

devices. These include: 

1. Side Rail Ladder Jack – 

(Over the rail and rung) 

This style of jack is installed onto the railing and 

rungs of a pair of extension, or single, ladders. 

The planking is then slid into position along the 

side of the bracket to create a work platform. 

Side Rail Ladder Jack

Photo courtesy of ACRO Building Systems, Inc.

PLANKING

2. Two or Three Rung Bracket Ladder Jacks –

(Over the rung only)

This style of jack hooks directly onto two or 

three ladder rungs. With these types of ladder 

jacks, planking may be placed on top of the 

bracket jacks to create a working platform.

2-Rung Bracket Jack 3-Rung Bracket Jack

Photos courtesy of Werner Co Services, Inc.

Setting-Up Ladder Jack Scaffolds 

Before each use: 

• Inspect all scaffold components for damage.

• Verify that all parts are working and ensure 

that all nuts are tightened.

• Do not use bent, cracked, damaged or 

substitute parts. 

• If using a two- or three-rung bracket jack, 

ensure that the rectangular brackets are fitted 

securely onto the ladder rungs in accordance 

with manufacturer’s specifications. 

• If using the side rail ladder jack, secure the 

upper round hooks and the lower brackets of 

the device onto the ladder’s side rails, then 

rest the brackets onto the rungs, and secure 

the platform gusset plate onto the adjustable 

notches at center. (See Figure #1).

• The ladder jack must be designed and 

constructed so that it will bear on the side rails 

and ladder rungs or on the ladder rungs alone. 

If bearing on rungs only, the bearing area 

must include a length of at least 10 inches 

(25.4 cm) on each rung [29 CFR 1926.452(k)(3)].
• Ensure that the bracket jack is adjusted so that it 

is parallel to the ground to create a level platform.

• Securely tighten the ladder jack’s wing nuts to 

prevent slippage during use.

• If the scaffold system is defective, tag and 

promptly remove it from service. 

Figure #1

Illustration courtesy of ACRO Building Systems, Inc.

Upper Round Hooks

Lower Brackets

Adjustable 

Notches

Using Ladder Jack Scaffolds 

• Extension ladders must not be separated to 

create two ladders.

• Keep the areas around the base of all ladders 

clear to prevent trip-and-fall hazards. 

• Avoid setting ladders up in high traffic areas 

or barricade areas near the base of the ladder.

• Keep ladders on stable and level surfaces, 

unless secured, to prevent accidental 

displacement.

• Ladders must be secured or provided with 

slip-resistant feet when used on slippery 

surfaces. 

• Workers should avoid electrical hazards and 

look for overhead power lines before handling 

ladders. 

• Workers should not use metal ladders near 

power lines or exposed energized electrical 

equipment.

• Keep platforms clear for working activities.

Platform Requirements 

• Two workers are recommended when 

installing planking onto jack bracket supports 

for scaffolding.

• Do not paint or plaster scaffold planks, and if 

paint or plaster is observed, promptly remove 

the plank from service.

• Do not use ladder jack scaffolding to 

support a platform higher than 20 feet (6.1m) 

[§1926.452(k)(1)].

• Do not bridge scaffold platforms together 

[§1926.452(k)(5)]. (This practice often causes 

the center of the platform to overload.)

• Each ladder jack scaffold platform must be at 

least 12 inches (30 cm) wide [§1926.451(b)(2)(i)].

When choosing a straight or extension ladder, 

make sure that its length allows you to set it up 

at the required angle, using the 4-to-1 Rule. ©WorkSafeBC. Used with permission.

Suggested Guidelines 

[29 CFR 1926 Subpart L, Appendix A(2)(k)]

• The maximum intended load for a ladder jack 

scaffold is 25 lb/ft2. 

• No more than two workers may occupy a 

platform at any one time. 

• The maximum span between supports is 

8 feet.

Training 

• The training requirements of 29 CFR 1926 

Subparts L – Scaffolds (§1926.454) and X – 

Stairways and Ladders (§1926.1060) apply to 

ladder jack scaffolding. 

• Employers must provide training for workers 

in hazard recognition, and procedures for 

controlling or minimizing hazards, when 

working on ladders and scaffolding. 

• Employers must ensure that workers use 

ladders are trained by a person competent in fall 

hazards, fall protection systems, the maximum 

intended load-carrying capacity of ladders, and 

the proper construction, use, placement and 

care required when handling ladders.

• Employers must ensure that workers involved 

in erecting, disassembling, moving, operating, 
repairing, maintaining, or inspecting 

scaffolding are trained by a person competent 

in hazard recognition.

Which OSHA standards apply to Ladder 

Jack Scaffolds?

Several OSHA standards apply to construction 

operations involving the use of ladder jack 

scaffolding, including:

• Ladder Jack Scaffold: A platform resting on 

brackets attached to ladders [§1926.450(b)];

• Supported Scaffold: One or more platforms 

supported by outrigger beams, brackets, 

poles, legs, uprights, posts, frames, or similar 

rigid support [§1926.450(b)]; 

• Ladder Jack Scaffolds: requirements applicable 

to specific types of scaffolds (29 CFR 1926 

Subpart L – Scaffolds), including requirement 

that all ladders used to support ladder jack 

scaffolds meet the requirements of Subpart X – 

Stairways and Ladders) [§1926.452(k)];

• Non-Mandatory Guidelines: 29 CFR 1926 

Subpart L, Appendix A – Scaffold Specifications. 

Ladder Requirements 

• All ladders used to support ladder jack scaffolds 

must comply with 29 CFR 1926 Subpart X – 

Stairways and Ladders [§1926.452(k)(2)]. 

• Exception: Job-made ladders must not be 

used to support ladder jack scaffolds.

Fall Protection Requirements 

• Employees working above 10 feet (3.1 m) on 

a ladder jack scaffold must be protected from 

fall hazards by a personal fall arrest system 

(PFAS) [§§1926.451(g)(1) & (g)(1)(i)]. 

• Personal fall arrest systems for scaffolds 

must meet the requirements of §1926.502(d) & 

§1926.451(g)(3). 

• The maximum distance from the face for 

plastering and lathing operations must be 

18 inches (46 cm) [§1926.451(b)(3)(ii)].

• The front edge of all platforms must not be 

more than 14 inches (36 cm) from the face of 

the work, unless guardrail systems are erected 

along the front edge and/or personal fall arrest 

systems are used [§1926.451(b)(3)].

OSHA’s Scaffolding e-Tool

• OSHA’s Scaffolding e-Tool provides 

information on the requirements that apply 

to specific types of scaffolding and ways 

to recognize potential hazards and identify 

controls, at: www.osha.gov/SLTC/etools/

scaffolding/supported.

Workers’ Rights

Workers have the right to:

• Working conditions that do not pose a risk 

of serious harm.

• Receive information and training (in a 

language and vocabulary the worker 

understands) about workplace hazards, 

methods to prevent them, and the OSHA 

standards that apply to their workplace.

• Review records of work-related injuries 

and illnesses.

• File a complaint asking OSHA to inspect 

their workplace if they believe there is a 

serious hazard or that their employer is not 

following OSHA’s rules. OSHA will keep all 

identities confidential.

• Exercise their rights under the law without 

retaliation, including reporting an injury or 

raising health and safety concerns with their 

employer or OSHA. If a worker has been 

retaliated against for using their rights, they 

must file a complaint with OSHA as soon as 

possible, but no later than 30 days.

For more information, see OSHA’s Workers page.

How to Contact OSHA

For questions or to get information or advice, 

to report an emergency, fatality, inpatient 

hospitalization, amputation, or loss of an eye, or to 

file a confidential complaint, contact your nearest 

OSHA office, visit www.osha.gov or call OSHA at 

1-800-321-OSHA (6742), TTY 1-877-889-5627.

This is one in a series of informational fact sheets highlighting OSHA programs, policies or standards. 

It does not impose any new compliance requirements. For a comprehensive list of compliance 

requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. 

This information will be made available to sensory-impaired individuals upon request. The voice phone 

is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.

DOC FS-3857 04/2016