Resources
Setting Standby and Portable Generators
In Short
A generator has to land square to the anchor bolts and dead level. That needs a cured pad. It also needs your electrician standing there when it comes down.
2 min readUpdated July 2026
Generator placement means craning a standby or portable unit onto its pad, roof or platform and setting it square to the anchor bolts and conduit stub-ups. The pad must be cured and level before the crane arrives. Having your electrician on site while the hook is still attached saves a day of rework.
Pads, Roofs and Raised Platforms
A standby generator is a heavy, awkward box with a flat bottom and no obvious place to grab. Most of them land on a concrete pad beside the house or the building. Some go on a roof next to the equipment they back up. Some go onto a steel platform to get them above a walkway or out of a drainage path. Each of those changes the pick, and none of them changes the requirement that the unit arrives square and level.
Portable units weigh less and get moved more often. With those, access is the problem rather than weight: a fenced equipment yard with no drive-in, a rooftop with a parapet in the way, or a pump house doorway narrower than the frame of the machine.
Cure Time, Level and the Bolt Pattern
Green concrete is the single most common reason a generator set gets pushed a week. A pad that feels hard on top is not necessarily a pad ready to take a concentrated load and an impact wrench torquing anchors into it. Ask the concrete crew for the date it is ready to load, then book the crane after that date rather than hoping.
Level matters more than most people expect. Engines have oil pans and fluid sight gauges that assume the machine sits flat. The pad gets checked with a level while the unit is still on the trailer, not after, because shimming a machine that is already bolted down turns into a long afternoon.
Then there are the anchors. Cast-in anchor bolts have no give whatsoever. If the pattern is already in the concrete, the unit has to come straight down onto it inside a very small window, with a hand on each end guiding it. If the anchors get drilled after the set, you gain some room to slide the machine, but only if the rigging can still lift it a fraction of an inch to shift it.
Fuel Lines, Gas and the Conduit Stub-Ups
Almost every generator has a fuel or gas connection and a bundle of conduit stub-ups poking out of the pad. Those stub-ups are the reason the unit has to be set square and not merely close. Rotate the enclosure a few degrees and the conduits come up in the wrong place inside the cabinet, and the electrician spends the rest of the day fighting geometry instead of terminating wire.
The sequence works best when the electrician or the gas fitter is standing there while the crane is still hooked on. Set the unit, check it against the stub-ups and the gas stub, adjust while the hook can take the weight back, then release. A few minutes of adjustment with the boom overhead beats a day of rework after the truck leaves.
Swapping an old unit out and a new one in on the same visit is routine and it is the efficient way to do it. The old machine gets disconnected and drained by the trade that owns it. We pick it off the pad and set it on your trailer or aside in the yard, then the new one goes down. A single setup, and the pad sits open for part of a morning instead of a week.
How the job runs
Our Process
Step 1: Confirm the pad is ready to load
We ask for the pour date and the concrete crew's word that the pad will take a load. If the answer is uncertain, the sensible move is to shift the lift a few days rather than crack a new pad.
Step 2: Map the anchors and the stub-ups
Before rigging, we look at the bolt pattern, the conduit locations and the gas or fuel stub. That tells us which way the unit has to face and how tight the landing window really is.
Step 3: Rig level and bring it in square
Slings go to the lifting lugs on the frame or the enclosure base. The unit hangs flat, a tag line keeps it from rotating, and it comes down oriented rather than being spun on the pad afterward.
Step 4: Hold the hook until it checks out
Level gets confirmed, the bolt holes get eyeballed against the anchors, and your electrician gets a look at the stub-ups. Only then does the rigging come off.
Scope
What Is Included
- Old unit picked off the pad and staged if this is a swap
- Rigging matched to the unit and its lifting lugs
- Set square to the anchor pattern and conduit stub-ups
- Level confirmed before the hook is released
- Coordination on site with your electrician or gas fitter
Answers
Frequently Asked Questions
How do I find out what my generator weighs?
Start with the model plate on the enclosure, then check the manufacturer spec sheet for that model with the enclosure and base tank included. Wet weight with fuel in the base tank is the number that matters, not dry shipping weight.
Can you put a generator on a roof?
Yes, if the structure is built for it and someone has confirmed the roof can carry the unit at that location. The lift itself is straightforward. The engineering call about the roof is not ours to make.
Does the pad have to be finished before you come?
Yes. The pad needs to be poured, cured to the point it will take load, and reasonably flat. Setting a machine on green concrete risks the pad, the anchors and the alignment all at once.
Will you haul the old generator away?
We can pick it and set it on your trailer or in a spot you choose. Hauling and disposal are yours to arrange, so it is worth having that trailer on site the same morning we do the swap.
Do you need my electrician on site?
It is strongly worth it. Having the electrician there while the hook is still attached means an alignment problem takes minutes instead of becoming a return trip for everyone.
More Guides
- Equipment Setting PackageMachinery, tanks, containers and modular sections set square to the anchors already in your slab, rigged from the frame when there are no lifting eyes.
- Site Preparation ChecklistWhat to clear, move, unlock and check before a crane arrives. A prepared site keeps the visit short and stops problems being found at the worst moment.
- Choosing the Right CapacityChoosing between the 22-ton and 40-ton boom truck is weight, distance and setup room together. Here is how the call gets made and what to send.
- Ground Conditions and OutriggersA crane puts its weight through four small pads. Here is what makes ground good or bad for outriggers, and what caliche and buried trenches mean here.
- Machinery PlacementSetting lathes, presses, compressors, tanks and pumps: finding lift points, protecting panels, measuring doorways and moving gear inside a yard.
- How Mobile Crane Service WorksA mobile crane brings the machine and the operator to your site. Here is what happens from the first phone call through setup, the pick and pack up.
- Capacity and Reach ExplainedA 40-ton crane will not lift 40 tons at full boom. Here is what capacity ratings, load radius and 142 feet of reach actually mean for your job.
- Site Preparation ChecklistWhat to clear, move, unlock and check before a crane arrives. A prepared site keeps the visit short and stops problems being found at the worst moment.
- What to Expect on Lift DayA walkthrough of lift day from arrival to departure, including how long each stage takes, what you can do, and why setup takes longer than the pick.
- HVAC Unit Crane Placement GuideHow rooftop package units and condensers get craned on and off, how the work is sequenced with your HVAC contractor, and what a curb mismatch means.
- Truss Lifting Process and SafetyHow roof trusses get set with a boom truck: staging bundles, spreader bars, bracing, wind limits and keeping the crane in one position along the wall line.
Ready to schedule your lift?
Tell us the load, the site and the timing. We will confirm capacity, access and a window.