Elevator Selection Guide: Types, Floors and Uptime

Start with height and traffic, not with a brand

Three inputs settle most of the decision: how far the car has to travel, how many people it has to move in the busiest part of the day, and what the building can physically accommodate.

Travel distance is the single most useful filter because it is fixed by the building rather than by preference. A three-storey building rarely justifies the machinery that a thirty-storey tower needs, and the reverse is just as firm: no amount of budget makes a low-speed system serve a tall shaft efficiently.

Traffic is the second filter, and it is the one that gets skipped most often. Two buildings of identical height can need completely different handling once the flow of people at the morning peak is measured. A residential building moves people slowly and predictably. An office building concentrates the same population into a twenty-minute window.

Working in this order also protects the budget. Once the system family and the car count are fixed, the remaining specification work is about finishes, controls and service levels, which is where supplier comparison is actually meaningful. Brand-first selection tends to produce an installation that is technically legal and financially difficult, because the machinery was chosen for reasons that had nothing to do with the shaft.

How the three mainstream systems work

Almost every passenger elevator sold today belongs to one of three families, and the difference between them is mechanical rather than cosmetic.

Hydraulic elevators lift the car with a piston, traction elevators lift it with a rope, and machine-room-less elevators are traction systems that have moved the drive into the shaft. Understanding which mechanism is doing the work makes the rest of the selection, including the cost and maintenance arguments, far easier to follow.

Those differences are not academic. The mechanism determines which buildings each family can serve at all, how much energy the installation consumes over its life, and what the maintenance team has to reach on a service visit. A hydraulic installation puts the working parts at the bottom of the shaft. A machine-room-less installation puts them at the top of the car, and a conventional traction installation puts them in a room the architect has to find space for.

Mechanism also sets the shape of the shaft. A traction installation needs a counterweight travelling beside or behind the car, which widens the shaft or changes its proportions. A hydraulic unit needs a cylinder standing under the car, or a piston fixed to the base, which drives the pit depth. A machine-room-less installation removes the room but keeps the counterweight, so the shaft footprint ends up close to a traction shaft while the building loses the plant space above it. Getting those three geometries onto the drawing early is what stops a system from being specified and then quietly deleted.

Choosing by building height

Height alone will not finish the selection, but it will remove the systems that cannot do the job, and that is the fastest way to shrink a long list.

Set the number of floors next to the mechanism and the picture becomes practical. The ranges below are the published industry figures already carried on this page, grouped by the building height they are normally applied to. They describe what each family is generally used for, not what any single model is certified to do.

Read the table as a filter rather than a verdict. A low-rise building with a generous machine room can still take a geared traction installation, and a mid-rise building with a very short shaft may not need the full travel capability of the mid-rise recommendation. The point of the table is that some combinations are not worth pricing at all, and cutting those out early saves the most time in the tender process.

Two habits keep the filter honest. First, confirm the travel distance from the finished floor levels in the approved drawings instead of estimating it from the number of storeys, because a tall ground floor or a double-height lobby changes the figure. Second, treat the floor count as the start of a conversation about traffic: a hospital and a hotel of the same height do not have the same elevator requirement.

A word on traffic, because it is the input that decides how much machinery the band actually needs. The floor count tells you which bands are plausible; traffic tells you how many cars and how much speed the building needs inside the chosen band. A single-tenant building with predictable hours can be served by one car at a modest speed, while a lobby that empties at six in the evening may need a second car or a faster one. Both answers sit inside the same height band, which is why the table filters the field rather than settling it.

Hydraulic and MRL elevators: the energy and environmental trade-off

The comparison that decides most low-rise projects is not price against price. It is energy consumption and fluid handling against the floor area a machine room would take.

Both families can serve the same low-rise building. They differ in where the working parts sit, how much energy the machine consumes on a normal day, and what has to happen at the end of the equipment's life. Those three differences are the ones that survive the tender and show up in the operating budget.

The environmental argument is the one that has shifted the market. Because of the energy and fluid-handling limitations, hydraulic installations have been declining in share, and the published guidance on this page already recommends machine-room-less traction in preference where the site permits. That is a statement about system direction rather than about any single specification, and it is worth confirming against current local requirements before the decision is locked in.

Cost still matters, and in a low-rise building with an awkward shaft the hydraulic option can be the only one that fits without structural work. The practical test is to price both families against the same duty, then compare the energy and maintenance estimates over the same period. Comparing a hydraulic installation's first cost with a traction installation's twenty-year cost is the most common way to reach the wrong conclusion.

Retrofit work adds a constraint that new build does not have. Where the shaft already exists, its dimensions decide the field before energy or upkeep is discussed, and a hydraulic installation is often replaced in kind because the pit and the cylinder position are already built. Where the shaft allows it, moving to machine-room-less traction during a modernization is worth pricing, because the difference in running cost accumulates over the remaining life of the building.

Cost efficiency in three parts

A single number for the price of an elevator hides the fact that the three components of cost move in different directions.

Split the question into installation, energy and upkeep and the choice becomes clearer. Installation is paid once and is the easiest figure to compare. Energy is paid every year and tracks the mechanism. Upkeep is paid on a schedule and depends on what the maintenance team has to reach and how often it wears out.

The direction of travel is the useful takeaway. A building that is sensitive to first cost will lean hydraulic. A building that will be operated for decades and is sensitive to the annual bill will lean machine-room-less traction, even though it costs more on day one. Neither answer is universally right, and the wrong way to settle it is to compare only the quotations.

Energy deserves a second look because it is the component that compounds. A difference in consumption that looks small in a single year becomes a significant line in a twenty-year operating budget, and it is the one item a supplier is least likely to volunteer at the tender stage. Ask for the consumption basis in writing and compare it with the traffic the building actually expects.

Comparing quotations gets easier when the three parts are separated on the page. Ask each supplier to state the installation scope, the estimated energy consumption with the basis behind it, and the maintenance schedule with its response times, then compare line by line. A lower installation figure paired with a higher energy estimate and a thinner maintenance scope is not a cheaper elevator; it is the same money distributed differently over a longer period.

Maintenance and safety: the four workstreams

Whatever system ends up in the shaft, four workstreams keep it reliable, and all four have to be funded from the first year rather than added after a failure.

The published guidance on this page sets out scheduled inspections, preventive maintenance, personnel training and emergency preparedness. Put them next to a tender document and they become a set of questions a buyer can ask before signing, which is more useful than a general assurance that maintenance is included.

Two of the four workstreams are habitually underestimated. Training matters more on machine-room-less installations, because the drive sits in the shaft and the technician reaches it from the car top rather than from a room with clear floor space. Emergency planning matters more than the schedule suggests, because the response to an entrapment is a procedure rather than a repair.

Brake and rope condition deserve particular attention on traction systems, since worn ropes reduce traction and raise the risk of the car slipping. On hydraulic installations the fluid circuit takes the place of that concern: leaks, pressure loss and the condition of the valves are the items that determine whether the installation behaves as designed in its tenth year.

A service contract is only as good as the access it assumes. On a machine-room-less installation the technician works from the top of the car, so the plan has to include the safety provisions for that position and the time it takes to set them up. On a conventional installation the machine room has to stay clear, dry and reachable, which is a building management task rather than a supplier task, and one that tends to lapse quietly.

Reading the published speed and travel figures

Most of the numbers used in elevator brochures describe the outer edge of a family rather than the performance of the unit being quoted.

Speed and travel are published as family ranges, and they are usually written in imperial units. Knowing which figure belongs to which mechanism stops a comparison from sliding into apples and oranges, which is the most common way a technically sound shortlist ends up with the wrong system on it.

The practical consequence is that a quotation quoting a family maximum tells you what the family can do, not what the building will get. When two suppliers offer different systems at similar prices, compare them against the actual travel distance and the actual daily trip count. A gearless unit running a short travel is not efficient, and a hydraulic unit running traffic it was never meant to move will consume more energy than the first-cost saving is worth.

It also helps to know which of the published numbers can be traded and which cannot. Speed can be reduced without changing the mechanism, and the reduction usually lowers the cost. Travel cannot be reduced without moving the building, and it is the figure that closes off whole families. When a quotation sits close to a published travel limit, treat that as the risk item in the pack and ask what happens above it.

Check the local rules before you shortlist

Building regulations have shaped which systems are available where, and the position differs from market to market.

The clearest example is machine-room-less design. As the material on this page records, building codes in the United States initially restricted it by prohibiting drive mechanisms inside shafts. The restriction has eased as regulations evolved, but the sequence matters: the code question has to be answered before the system is chosen, not after the drawings are finished.

The same discipline applies to the parts of the installation that are easy to overlook: the electrical supply the drive needs, the fire strategy for the shaft, and the accessibility requirements that the car and the landings have to meet. None of these is exotic, and all of them are cheaper to accommodate on paper than in a built shaft.

For residential work, the system families described here are only part of the market. Compact screw-driven platforms and platform lifts have their own cabin, shaft and travel conventions, and they are covered in the product pages linked below rather than in this guide. Where a building is residential and the travel is short, compare the two standard routes before assuming that a conventional passenger installation is the only option.

Two questions for your site

Height removes the impossible systems. Two further questions remove the uncomfortable ones, because the site either has room for the plant or it does not.

Answer the two questions below and the locator returns the system band that fits the combination, together with the trade-off that comes with it. The answers come from the same published ranges used in the table above.

The locator is deliberately blunt, because the questions that change the answer most are blunt. What it cannot do is size the car or set the speed. Those come from measured traffic, and they are the numbers a supplier needs in order to quote something that will actually be built.

The locator answers the system question; the site survey answers everything else. Take the shaft dimensions, the pit and overhead clearances and the electrical supply into the same meeting, and the two halves of the decision line up. A recommendation that arrives without those measurements is a starting point rather than an answer, however confidently it is delivered.

Technology trends that change the answer

Four developments are already affecting specification decisions, and they tend to favour whichever system can absorb them most cheaply.

These trends are described in the material published on this page and are worth reading as directional rather than as features to be ordered. Each one shifts the weight between the three families, and each one has a maintenance or electrical implication that belongs in the budget.

Read together, the four trends all move in the same direction: more intelligence, less energy, and less physical weight per unit of travel. That favours systems with a modern drive and a control package that can be updated, and it penalises installations whose energy profile is fixed by the mechanism itself.

The procurement implication is straightforward. When a supplier describes a system as future-proof, ask which of the four items above the installation can absorb after handover and which would require replacing the machinery. Items that can be delivered by a software update and a sensor kit are cheap to adopt later. Items that are locked into the drive type are not.

None of the four trends redraws the height bands in the table above. What they change is the cost balance inside each band, and they do it gradually rather than at once. A building specified today will still be classified by its travel and its traffic in twenty years; only the running cost attached to that classification is likely to move.

What to prepare before you ask for a quote

Suppliers price what they are given. A brief with the building facts in it produces comparable quotations; a brief with a floor count and a deadline produces guesses.

The list below is the set of inputs that determines whether two quotations can actually be compared. Work through it before the first call, and the conversation moves from brand preference to duty and cost.

Two of the ten items are the ones that most often go missing. The traffic figure is usually an estimate rather than a measurement, which is why car sizing drifts. The written position from the authority is usually assumed rather than obtained, which is why a system that was priced in good faith turns out to need a variation order.

With the brief assembled, the comparison becomes a like-for-like exercise. Two quotations on the same duty, the same site constraints and the same maintenance expectations can be compared on cost and on energy, and the answer will usually be clear. Without it, the cheapest-looking quotation is often the one with the most assumptions buried in it.

Keep the completed checklist with the tender documents. When the quotations come back, the brief becomes the yardstick: any figure that cannot be traced to an item on the list is an assumption, and assumptions are what make two apparently similar prices impossible to compare. It also gives a supplier a reason to answer the question that was actually asked.

Frequently asked questions

The questions below are the ones that come up most often once a project team starts comparing systems rather than suppliers.

One question sits behind all ten: what is the building being asked to do, and for how long. Answer that in numbers and the system family usually chooses itself.

Imperial figures in metric

Most published elevator figures are in feet and feet per minute, while most site drawings are in metres and millimetres. The converter below closes that gap.

Type into either box of a row and the other side follows. The factors are standard unit conversions, so the result is arithmetic rather than specification, and nothing here replaces the figures in the approved drawings or the supplier's sheet.

Two conversions are worth keeping in mind while reading a specification. A speed of 500 fpm is a little over 2.5 metres per second, and a travel of 250 ft is a little over 76 metres. Those two numbers alone tell a reader whether a quotation is describing a low-rise installation or something aimed at a tall building.

The reverse direction is just as useful. Where a supplier states a travel in metres and the published family range is in feet, convert the quotation rather than the range, so that the comparison stays anchored to the document that will actually be built. Mixing a converted range with an unconverted quotation is how a project ends up outside the limit without anyone noticing.