Two Post Lift Site Survey Checklist: What We Check Before Install

Before we ship a single bolt, we run every job through our two post lift site survey checklist, because the single biggest cause of installation delays and change orders isn’t the lift itself — it’s a bay that wasn’t measured right. We’ve been installing and servicing two post lifts across Iowa long enough to know that a fifteen-minute survey up front saves a full day of headaches on install day. Whether you’re a one-bay home garage or a ten-bay dealership service department, the same checklist applies, and we walk every customer through it before we quote equipment or schedule a crew.

Ceiling Height and Overhead Clearance

The first item on any two post lift site survey checklist is overhead clearance, and it’s the number one reason we turn people away from a model they’ve already fallen in love with online. You need enough height for the vehicle at full rise plus the arm assembly and safety locks, and most asymmetric two post lifts need somewhere in the 12 to 14 foot range depending on the model and the vehicle you’re lifting. We measure from the finished floor to the lowest overhead obstruction — not just the ceiling, but HVAC ductwork, sprinkler heads, light fixtures, and support beams that cut across the bay.

A lot of Iowa pole barns and older shop buildings have trusses or purlins that drop clearance in spots that aren’t obvious until you’re standing under them with a tape measure. We’ve had customers assume they had 14 feet because that’s what the building plans said, only to find a gas line or conduit run hanging two feet lower right where the lift needs to go. This is why we do the measurement in person or ask for photos and exact numbers before we finalize a quote — guessing on ceiling height is how lifts end up sitting in a warehouse because they don’t fit.

Concrete Slab Thickness and Condition

Every two post lift site survey checklist has to include a hard look at the slab, because the lift is only as strong as what it’s anchored into. Most two post lifts call for a minimum of 4 inches of structurally sound, unreinforced or properly reinforced concrete with a minimum compressive strength, and older Iowa buildings sometimes have thinner slabs, especially in additions or lean-tos built onto the original structure. We ask for the age of the slab, whether it’s been core drilled or cracked, and whether there’s any radiant heat or in-floor plumbing running through the anchor zone.

We also check for existing cracks, expansion joints, and previous anchor holes from lifts that came out before. Anchoring into cracked or contaminated concrete voids the anchor manufacturer’s rating and creates a real safety risk once vehicles start going up and down. If your slab is thin, cracked, or unknown, we’ll talk you through options, including pouring a new footprint before the lift arrives, so the survey happens before money gets spent, not after a lift shows up that can’t be safely anchored.

Bay Width and Column Spacing

Column spacing gets overlooked more than any other item on a two post lift site survey checklist, and it causes real problems on the vehicles side, not just the building side. You need enough width between columns for the widest vehicle you’ll service to open both doors, plus enough clearance on each side to walk around and work. Most shops need at least 12 feet of usable bay width for a standard asymmetric lift, more if you’re running duallies, extended vans, or heavy trucks with wide door swings.

We also look at what’s next to the bay — support columns, tool chests, other lifts, or walls that limit how wide you can actually set the columns even if the floor space technically allows it. A lift that’s too narrow forces techs to fold mirrors or squeeze doors open at an angle, which slows down every single job that goes on it. We measure actual usable width, not just the number on the building blueprint, because blueprints and reality don’t always match in shops that have been remodeled or added onto over the years.

Electrical Service and Power Location

Power requirements are part of every two post lift site survey checklist we run, and they’re easy to underestimate. Most two post lifts run on a dedicated circuit, and the voltage and amperage depend on the motor size and model. We confirm what’s already run to the bay, whether it’s a dedicated circuit or shared with other equipment, and where the disconnect and control box need to sit relative to the columns.

Running new electrical after a lift is already anchored is far more expensive and disruptive than planning it during the survey phase. We’ve seen shops have to cut into finished floors or reroute conduit around a lift that’s already in place because power wasn’t part of the original conversation. If your building is older or you’re not sure what’s currently run to the bay, we’ll ask you to have an electrician check panel capacity and existing circuits before we finalize equipment, so there are no surprises when the crew shows up to install.

Vehicle Types and Weight Capacity

No two post lift site survey checklist is complete without knowing exactly what you’re lifting, because capacity and lift point geometry depend entirely on the vehicles in your bay. A shop that services mostly sedans and light trucks has very different needs than one lifting three-quarter-ton trucks or vans with unusual frame rails. We ask about your heaviest regular vehicle, your tallest vehicle, and whether you ever bring in anything unusual like a lifted truck or a low sports car that needs different arm configurations.

Undersized capacity is a safety issue, not just an inconvenience, and oversized capacity for your actual work is wasted money. We size the lift to your real fleet, not the biggest number in the catalog, and we factor in future growth if you’re planning to take on new types of work. This step of the survey directly drives which model and arm configuration we recommend, so it happens before, not after, we send a quote.

Drainage, Lighting, and Bay Layout

Beyond the structural items, a thorough two post lift site survey checklist covers how the bay functions day to day. We look at floor drains near the anchor pattern, since cutting into a drain line changes the anchoring plan, and we check existing lighting to make sure techs can actually see the underside of a raised vehicle without dragging in a work light every time. We also look at door swing, traffic flow in and out of the bay, and where tool carts and equipment currently live.

Getting the layout right the first time avoids relocating a lift a year later because it turns out the columns block the overhead door track or crowd a walkway. We sketch the bay with the customer, mark where the lift will sit relative to doors and other equipment, and confirm there’s enough room around the perimeter for safe operation and maintenance access. This is usually the last item we check, but it matters just as much as ceiling height when it comes to a shop that actually works well every day.

Putting the Survey Results to Work

Once we’ve been through every item on the two post lift site survey checklist, we put it all together into a recommendation — model, capacity, arm style, and anchoring plan — rather than just handing you a spec sheet and hoping it fits. If you want to see the full process in more detail, our two post lift site survey guide walks through how we document each measurement, and our lift site survey checklist covers the same process for other lift types if you’re weighing options beyond a two post.

We also point customers toward our pre-purchase site survey checklist if you’re still comparing lifts before committing to a brand or model. The goal across all of it is the same: catch every clearance, power, and slab issue on paper, before a crew and a lift show up to a bay that can’t accept it. That’s the difference between an install day that goes smoothly and one that turns into a change order.