Difference Between Hydraulic And Traction Elevators​ in  Existing Homes 

When retrofitting elevators in older buildings, should you choose a traction or a hydraulic home elevator? Focusing specifically on the context of retrofitting existing properties, we compare these two options side-by-side to help you select the home elevator type best suited to your specific building project.

Characteristics of Traction-Type Residential Elevators in Retrofit Projects for Older Homes

Traction elevators rely on a traction machine and steel belts or wire ropes to move the elevator car, and they incorporate a counterweight system.

Advantages: Traction elevators operate smoothly and quietly, offer high speeds, and feature low energy consumption over long-term use.

 Furthermore, the maintenance system for traction-based systems is well-established, and components are highly standardized, making them an excellent choice for long-term residential use.

Disadvantage: Space must be reserved for the counterweight, which requires a wider elevator shaft for a given car size; additionally, there are strict minimum requirements for the top-floor height and the pit depth.

Traction elevators are highly suitable for renovation projects in older buildings, provided that a compliant elevator shaft can be constructed and the dimensions of the top floor and pit meet the minimum requirements for elevator installation.

Characteristics of Hydraulic Home Elevators in Retrofit Installations for Older Residences

Hydraulic elevators use a hydraulic cylinder to lift the elevator car; they lack a counterweight system and therefore do not require space for a counterweight, resulting in more efficient use of space within the elevator shaft.

Advantages: For the same internal car dimensions, hydraulic elevators require a smaller elevator shaft, resulting in higher space efficiency and a smaller overall footprint.

Furthermore, hydraulic elevators have lower requirements for the height of the top floor; they can be installed with a minimum overhead clearance of just 2.3 meters. This makes them an excellent choice for older buildings with limited floor-to-ceiling height.

The initial cost investment is low. It is highly suitable for 2–4 story residential buildings, allowing for effective budget control in renovation projects.

Disadvantages: There is a noticeable jolt during startup and shutdown, and long-term energy consumption is higher than that of traction type systems. Since the hydraulic system relies on seals to maintain pressure, the aging of these seals creates a long-term risk of hydraulic fluid leakage. Furthermore, the need to replace seals and hydraulic fluid results in ongoing maintenance costs.

Hydraulic home elevators are suitable for old villas where the elevator shaft space is extremely limited, the top-floor headroom is severely insufficient, and the existing structural conditions cannot meet the minimum requirements for a traction type elevator.

Comparison of Hydraulic and Traction Home Elevator in Existing House

We have created a comparison table between hydraulic elevators and traction elevators:

Comparative Analysis Focus on Existing Houses

Space Requirements

Traction elevators place their core components at the top of the shaft, saving space. Furthermore, they require minimal pit depth, only 200-300mm is needed. This solves the problem of limited space in existing residential buildings and eliminates the need for large-scale ground modifications.

Hydraulic elevators are relatively rare on the market, and they usually cannot be flexibly adjusted to fit the space of existing residences. They also require a deep pit, which causes significant damage to the original ground.

Durability and Long-term Efficiency

Traction elevators have fewer vulnerable parts and fewer potential failure points, and their technology is mature. Compared to hydraulic elevators, which are prone to problems such as oil leaks and aging, traction elevators are more durable.

In addition, traction elevators are quieter than hydraulic elevators, faster, and run more smoothly, but consume far less electricity.

Long-term Costs

Although the initial cost of a traction elevator is higher than that of a hydraulic elevator, the total cost of traction elevators is lower in the long run.

Traction elevators have low annual fixed costs, require fewer major repairs, and have a longer design lifespan; with proper maintenance, they can still be used 15-20 years later.  

Hydraulic elevators have the biggest hidden cost: oil leak repairs and cylinder replacements can offset the maintenance costs of several traction elevators in one incident.

Many people initially chose hydraulic elevators because of their low price, but after a few years of use, they began to regret it and were plagued by many problems. In the end, they replaced them with traction elevators.

Multi-story Residential Buildings

The main difference between traction elevators and hydraulic elevators is the height they can operate at. For existing residential buildings with higher floors, only traction elevators are available. For residential buildings with lower floors, both traction elevators and hydraulic elevators are options.

Security

Traction elevators have more comprehensive safety protection devices and a higher overall safety limit.

It has a safety clamp and speed governor that hydraulic elevators do not have. If the car falls out of control, the safety clamp will firmly lock the car onto the guide rail.

While hydraulic elevators have explosion-proof valves that can prevent them from falling rapidly, they have a unique safety hazard: as the sealing components age, the elevator will slowly sink.

Key Decision-Making Criteria for Selecting a Home Elevator for Existing Houses

The first step： Prioritize on-site measurement of three key dimensions: the available length and width of the elevator shaft, the height of the top floor, and the depth to which the pit can be excavated.

Step 2: Compare the site conditions against the civil engineering requirements for a traction home elevator; if the site meets these criteria, prioritize the traction-based solution.

If the civil engineering parameters are fixed and cannot meet the minimum requirements for a traction elevator under any circumstances, then consider a hydraulic elevator as an alternative. 

Note: When retrofitting existing buildings, try to avoid extensive cutting or reinforcement of the original load-bearing structure for the sake of installing a traction elevator; the more significant the alterations, the higher the structural risks and renovation costs.

The civil engineering baseline parameters for traction elevators are as follows:

Traction Backpack Home Elevator

Traction Gantry Home Elevator

Additional Considerations for Retrofitting Older Residential Buildings

In older buildings, the walls and floor slabs have aged over time, and their structural integrity has deteriorated. Regardless of the type of elevator ultimately chosen, it is essential to conduct a load-bearing capacity assessment of the floor slabs beforehand to ensure that the existing structure can support the load of the elevator.

Furthermore, an integrated aluminum-alloy and glass shaft system is an excellent solution for existing buildings. It eliminates the need for extensive structural modifications to the original walls, and both traction and hydraulic drive systems can be paired with this type of prefabricated shaft.

 FAQs

When retrofitting an elevator in an old building without a pit, which is easier to implement: a traction system or a hydraulic system?

Whether these two types of elevators can be retrofitted depends on whether the manufacturer offers corresponding models that do not require a pit. There are relatively few options available for pitless traction-type models; while there is a wider variety of pitless hydraulic models on the market, the load-bearing capacity of the floor slab must still be rigorously evaluated. 

Is there a high risk of oil leakage when installing a hydraulic elevator in an existing building?

If high-quality hydraulic cylinders and pipeline seals from reputable manufacturers are used—and provided that routine, scheduled maintenance is carried out—risks can be kept under control. However, hydraulic systems are inherently prone to seal degradation, making these components a critical area that requires ongoing, focused inspection. 

For an older villa, which type of wheelchair-accessible modification should be prioritized?

Traction-drive systems are the preferred choice; they offer smooth operation with gentle starts and stops, making them particularly well-suited for individuals with limited mobility or those using wheelchairs. Hydraulic systems should only be considered if the site’s structural conditions cannot meet the requirements for a traction-drive system.

How does a traction elevator work?

Most traction elevators currently used in residential buildings rely on a motor to drive a traction sheave; the system operates through the friction generated between the traction sheave and the steel ropes. One end of the steel ropes is connected to the elevator car, while the other is attached to a counterweight, which serves to offset the weight difference between the two sides.

What is the cost difference between hydraulic and traction home elevators?

Traction home elevators entail a higher initial investment, but they offer low failure rates, high durability, and lower long-term costs.

Although hydraulic elevators are often marketed as an “economical” option, they tend to incur higher long-term costs due to frequent breakdowns, the need for ongoing maintenance, and the eventual replacement of components (such as the hydraulic pump).

The equipment cost for a traction elevator is approximately $5,000–$25,000, while the equipment cost for a hydraulic elevator is about $3,900–$11,000. The average annual maintenance cost for a traction elevator is $300–$750, and for a hydraulic elevator, it is $500–$1,000.