A ladder that slips or falls is one of the leading causes of construction site fatalities in the United States. Most accidents happen not because of faulty equipment but because the ladder was set up incorrectly. This guide covers every step of the process so you can work at height without second-guessing your setup.
Recommended Extension Ladders
Before getting into the setup steps, here are three Werner extension ladders built to OSHA Type IA standards. Choose based on how high you need to reach.
1. Werner D6216-2 — 16-Foot Fiberglass Extension Ladder
Type IA rated at 300 lb. Best for single-storey work, gutter cleaning, and exterior painting up to 13 feet working height. Non-conductive fiberglass rails. Alflo rung joint prevents twist during use. Compact enough to transport in most vehicles.
2. Werner D6220-2 — 20-Foot Fiberglass Extension Ladder
Type IA rated at 300 lb. Reaches 17 feet working height, covering most two-storey residential work. Includes rope and pulley for easier extension. Non-conductive fiberglass rails. The most versatile size for homeowners who do regular exterior maintenance.
3. Werner D6228-2 — 28-Foot Fiberglass Extension Ladder
Type IA rated at 300 lb. Reaches 25 feet working height, suitable for two and three-storey buildings. Used widely in construction and facilities maintenance. Fiberglass non-conductive rails with Alflo rung joint. The professional standard for residential and light commercial work.
How to Set Up an Extension Ladder in 7 Steps
To set up an extension ladder safely: inspect it for damage, choose a flat stable surface, apply the 4-to-1 angle rule, extend the fly section to the correct height, raise the ladder, secure the top and bottom, then climb while maintaining three points of contact at all times.
🪜 Step 1: Inspect the Ladder
Before setting up, inspect your ladder for any defects or damage. A damaged ladder that fails under load can cause fatal falls.
- Check for any loose or missing parts
- Make sure the ladder feet work properly and swivel smoothly
- Ensure the rungs and side rails are intact and free from cracks
- Validate that the pulley, ropes, and rung locks are functioning correctly
🪜 Step 2: Choose the Right Location
Choosing a solid and level base makes all the difference. An unstable surface is the most common reason ladders slip at the base.
- Avoid setting up on wet, muddy, or slippery surfaces
- Keep away from doorways or areas with heavy foot traffic
- Ensure the area is clear of power lines, windows, and overhanging obstacles
🪜 Step 3: Determine the Correct Angle
Setting up at the correct angle is the most important safety step. Too steep and the ladder tips backward. Too shallow and the base slides out.
The 4-to-1 Rule
The ladder base should be one foot away from the wall for every four feet of ladder height. A 16-foot ladder needs its base 4 feet from the wall. A 20-foot ladder needs 5 feet. This produces a 75-degree angle, which OSHA identifies as the safest position for climbing.
- Prevents the base from sliding out
- Reduces the chance of the ladder tipping backward
- Balances the force across both side rails
- Provides the most stable climbing position
How to Measure the Angle
You can use these techniques to confirm the correct ladder angle:
- Visual method: Divide the ladder height by four. That number is how far the base should sit from the wall.
- Shadow method: On a sunny day, the shadow cast by the ladder on the ground should equal the distance from the base to the wall.
- Right-angle triangle method: Attach a 12-inch strip perpendicularly to a 48-inch strip. Place the long side on the ground with the short side against the ladder base to confirm the correct angle.
- Smartphone leveler app: An inclinometer app can measure the exact angle and confirm you are at 75 degrees.
Extra Tips
- Check the angle after fully extending the ladder, not before.
- If setting up the ladder on uneven ground, adjust each foot independently using levelers.
- Never overreach. Reposition the ladder instead of leaning sideways.
🪜 Step 4: Extend the Ladder
Follow these steps to extend your ladder correctly before raising it against the wall.
- Keep the ladder flat on the ground with braces locked and have one person hold it steady
- Pull on the rope to lift the fly section to the desired height
- Ensure the rung locks are securely engaged before releasing the rope
- Fully extend the ladder before raising it upright
🪜 Step 5: Raise the Ladder
Raising the ladder requires technique, not just strength. The walk-up method is the safest approach for one person.
- Stand at the ladder base, grip the rungs (not the rails), and lift
- Walk hand over hand under the ladder until it stands vertical
- If the ladder is too heavy, get a second person to help — do not force it
How to Raise an Extension Ladder by Yourself
- Clear the area: Remove any obstacles around the base and confirm stable footing.
- Position the ladder: Carry it to the building with the fly section against your body. Place it flat on the ground about 6 inches from the wall.
- Walk it up: Stand at the far end and gradually walk toward the wall, moving hand over hand up the rungs until the ladder stands vertical.
- Adjust the base: Lift the base away from the wall to set the correct 4-to-1 angle.
- Verify the locks: Confirm rung locks are engaged before climbing.
🪜 Step 6: Secure the Ladder
A correctly angled ladder can still slip if the top and bottom are not secured. This step is where most DIY users cut corners.
Securing the Top
Use ladder accessories to secure the top against the wall and protect surfaces from damage.
- Ladder stabilizer: A U-shaped bracket that straddles the roof edge, providing a wider contact point and keeping the ladder away from gutters and windows.
- Stand-off brackets: Fit onto the rungs and lean against the wall, creating a gap that distributes load and prevents surface damage.
Securing the Bottom
A spotter holding the base is the most reliable method. If no spotter is available, use ladder stoppers or spiked feet designed for outdoor use.
- The spotter should hold the rails firmly with feet planted, standing clear of the area directly beneath the ladder
- For soft ground, use spiked feet or a rubber base plate to prevent sinking
Securing an Unattended Ladder
- Place sandbags around the base for added stability in wind-prone areas
- Use ladder mitts on the top ends to prevent slipping against smooth walls
- Never leave an extended ladder unattended near public access areas
🪜 Step 7: Climb Safely
- Always maintain three points of contact: two hands and one foot, or two feet and one hand
- Never carry heavy objects while climbing — use a tool belt or rope-and-pulley system
- Face the ladder when climbing up and descending
- Do not lean sideways — move the ladder instead of overreaching
What is the Correct Way to Place an Extension Ladder?
Place the ladder on stable, flat ground and apply the 4-to-1 rule — the base sits one foot from the wall for every four feet of height. This produces a 75-degree angle. Once the base is secured, extend the fly section to the desired height and confirm the rung locks are engaged before climbing.
Which Side of an Extension Ladder Goes Against the House?
The base section goes at the bottom, with the rungs of the fly section facing toward you. This orientation gives you the correct grip on the rungs while climbing and prevents the ladder from flexing under load.
What is the Safest Angle for an Extension Ladder?
75 degrees is the safest angle. Apply the 4-to-1 rule to reach it. At 75 degrees, the ladder provides maximum stability and minimizes the risk of the base sliding out or the top tipping backward under the climber’s weight.
How Do You Know if an Extension Ladder is at the Correct Angle?
Check visually: the base should be one foot from the wall for every four feet of ladder height. For a 16-foot ladder that is 4 feet. For a 20-foot ladder that is 5 feet. You can confirm with a smartphone inclinometer app, the shadow method, or the right-angle triangle method described in Step 3.
How to Extend a Ladder Without a Rope
If your ladder does not have a rope and pulley (the 16-foot Werner D6216-2 does not ship with one), you can manually push the fly section upward.
- Position the ladder safely: Ensure stable, level ground and apply the 4-to-1 angle rule.
- Disengage the locks: Make sure the rung locks are disengaged before extending.
- Push the fly section up: Grip a rung of the fly section with both hands and push it upward firmly. Keep control at all times to prevent the fly section from dropping.
- Engage the locks: Once extended to the correct height, secure the rung locks.
- Double-check: Pull down firmly on the fly section to confirm the locks are holding before climbing.
Frequently Asked Questions
How far should an extension ladder extend above the roof or landing point?
OSHA requires the ladder to extend at least 3 feet above the roof edge or landing point. This gives you something to hold onto when stepping on and off the ladder at the top.
What size extension ladder do I need for a two-storey house?
A standard two-storey house is 20 to 25 feet tall. A 24-foot or 28-foot extension ladder gives you a working height that reaches the gutters and roof edge with the 3-foot overhang required by OSHA.
Can one person set up an extension ladder safely?
Yes, using the walk-up method described in Step 5. For ladders over 28 feet, a second person is strongly recommended. Beyond that height the weight and leverage required make solo setup a significant fall risk.
How do I stop an extension ladder from sinking on soft ground?
Use a base plate or board under the ladder feet to spread the load. Most Werner ladders include dual-action feet that can switch between flat mode for hard surfaces and spur mode for soft ground. Never set a ladder on soft ground without support.
How often should I inspect my extension ladder?
Inspect before every use. Check rungs, locks, ropes, and feet each time. A more thorough inspection including checking the rung joints and side rails for cracks should happen at least once a month if the ladder is in regular use.
Is it safe to stand on the top three rungs of an extension ladder?
No. OSHA prohibits standing on the top three rungs of an extension ladder. If you need to reach higher, you need a longer ladder. Standing on the top rungs removes your ability to maintain three points of contact and makes the ladder unstable.
Conclusion
Setting up an extension ladder correctly takes about two minutes when you know the steps. Inspect the ladder, pick a stable surface, apply the 4-to-1 rule, extend fully before raising, secure both ends, and climb while maintaining three points of contact. Every shortcut in that sequence increases your fall risk.
For more on ladder safety and selection, see our guides on the correct angle for a ladder, what size ladder you need for a two-storey house, and whether you can lean a ladder against a gutter.
