What size of crane do I need?

There are two major factors that have to be answered before you can choose your crane.

• What is the distance you are craning?
• What is the weight of the heaviest object(s) you are craning from that spot?

To determine the answers to these questions, you must answer a series of other questions to contextualize everything.

Where is the crane going to be placed?

Knowing where the crane is going to be placed and how it is going to be positioned in that spot are critical pieces of information. It determines the starting point of your distance calculation. Will the crane be parked on the street, in the driveway, or off the neighbouring property? When the average crane has a maximum reach of about 100-120 feet, the answer to this question can radically change the math on the distance calculation. The starting point is ALWAYS calculated from the middle of where the crane rotates, NOT the end of the crane truck.

Where is the crane trying to reach too?

This is the end of your distance calculation. The biggest mistake people make here is measuring only to the end of the item. You really need to measure from where the hook is attached to the object, which 9 out of 10 times is the middle of the object. The bigger the object (say a pool) being craned a long distance, the more important this is.

Did you take the crane outriggers into consideration?

When the crane is deployed, outriggers come out of the side of the crane. These help stabilize the crane and prevent it from tipping over sideways. The larger the crane, the bigger the outrigger footprint is required. Where you are planning to park the crane, does it have space for these to extend out the side?

Is the ground level on which the crane can park?

Most people do not realize the crane must be level to work safely. A crane that is not level is an accident waiting to happen. Most mobile cranes have outriggers that come out the side to balance and stabilize the truck. Those stabilizers have a limited distance of movement that they can lift the crane. If the ground is too uneven, you might be unable to level the crane. If the ground is on an incline that is too steep, you might also not be able to deploy it where you want it. That could increase the distance you need to reach if you also have to reach over some unsafe ground.

Is there any height obstructions?

Your standard stick crane usually cannot lower its boom more than 45 degrees without risk of falling over. That means a couple of things:

1. The crane can never reach the entire boom length because it must also go up for every foot out.
2. If a tall object is beside the crane truck that it has to go over, two things might happen.
   • The crane needs to move further away so the angles still work, increasing the distance the crane needs to reach.
   • The crane’s reach is reduced because it must reach taller to get over the object. This means the angle of degrees that the boom can bend down has been reduced because the crane is blocked by a house or tree, for example.

While the crane itself can move from side to side, it can only extend forward in one direction. That means that if an object like a tree or power line is in the way, it also has to go over it to reach where you want to go.

We should note here that knuckle cranes do not have the same restrictions as your standard stick crane. Knuckle cranes do not have a 45-degree restriction and have powerful jib attachments built into the boom for changing direction and increasing the amount of reach it can lift. You should always talk to a knuckle crane specialist on trickier or tight lifts to see what is and is not possible.

What is the weight you are trying to lift?

The most important thing to understand when craning is that the weight the crane can lift is constantly changing depending on several factors. To simplify this into layman’s terms, the further you want to reach, the less weight you can lift. Or the more weight you want to lift at distance, the bigger the crane you might need to do it.

For example, a crane that can lift 5000 pounds at 20 feet distance from the crane truck. It might be only 2000 pounds at 50 feet distance and 500 pounds at 100 feet distance. Every crane truck has what they call a load chart, which shows how much weight it can lift at what distance. While some trucks have similar charts, every chart is custom-designed for that specific crane truck. This is why knowing the weight and distance is so important. A bad guess here can mean the difference between success and failure.

I have the weight and distance. What is next?

Give those numbers to the crane company, along with some pictures of what you think you need. Let them tell you what crane you will need. While you might think you know which crane you need, you do not want to be caught ordering the wrong size. If you guess wrong, you must pay for that crane, regardless of whether the lift was done successfully or not. In the crane business, you are paying for crane time, including the time for the wrong crane to show up at your job site. Let the crane professionals confirm that your numbers make sense so you always get the right crane the first time.