For years Modular Elevator Manufacturing has been educating the public on elevators in general and the benefits of hydraulic elevators specifically. Hydraulic elevators are often times the absolutely best option for vertical travel, especially when it comes to low-rise applications. However, we have not spent an inordinate amount of time discussing many of the drawbacks. That is because there are very few and generally well understood. However, it has come to our attention that some of these drawback have taken on a life of their own and now live on in near mythic proportions.
So in this short article we are going to address the ups and downs of the hydraulic elevator, dispel myths and shed some light. This is not a sales pitch! After all you can buy a high-quality, commercial hydraulic elevator from any number of companies. We look at this article as a help to those that are truly curious about the best elevator for their current or future elevator project.
To keep me organized and to keep from jumping all over the place, I will address each point listed below. These are the largest complaints that many have about hydraulic elevators:
Believe it or not, there is merit to some of the claims made above, but the explanations are often ignored and this has led to more than one exaggeration. That begs the question, why would one perpetuate a misleading claim? I hate to say it, but sales and profit motives are usually big factors. If more money can be made, why sweat the small things like the truth and developing a reputation over time. After all, the elevator industry has such a stellar reputation, why damage it for a few dollars? Just kidding on the reputation crack. One of the biggest battles we face as an elevator manufacturer is the overall reputation of the industry as a whole.
Ask nearly any general contractor, building owner or architect and they will affirm they dislike the elevator business. In my experience and when doing independent research I have personally heard elevator companies described as bullies, untruthful, unreliable, unresponsive and overpriced. Do any of those descriptive terms surprise you? Unfortunately, probably not. So let’s just say that profit motives are powerful and can lead to some generalizations and exaggerations. But more than that, in the late 1990’s a new product was introduced to the American market. The MRL (machine room-less) traction elevator was rolled out with tons of fanfare and major investment from big elevator companies.
Logically, for that investment to payoff significant downward pressure was applied to sell up MRLs. Incentives were created, promises were made and poor comparisons were projected. Those sometimes false comparisons still ruminate in the minds of many. This coupled with ignoring hydraulic elevator technological improvements leads to a misunderstanding of facts and benefits. But let’s get to the list.
The first common complaint is that hydraulic elevators cost too much. Not necessarily in the upfront investment in installation, but in the Life Cycle Cost or LCC. The initial cost of a hydraulic unit runs around 35% less that a traction MRL. Not only is that true of pricing at Modular Elevator Manufacturing, but across the board, but what about maintenance and electricity? How does hydraulic stack up against MRL traction?
This question was answered by a study from of all places Thyssenkrupp. They were so interested in this question that they commissioned a report and then published its findings in a blog. The answer may surprise you. They found the following:
“We conducted Life Cycle Costing (LCC) research on low-rise elevators to help customers understand their economic and environmental impacts. LCC looks at the costs involved with a product or service over its entire lifetime. The study showed that over 25 years, the cost to maintain three-stop traction MRL is $173k compared to the same hydraulic MRL which cost $91k.”Myths about Low-Rise Elevators Means Realistic Costs to Building Owners – Tetley-Scott 2014
Keep in mind that is the cost to maintain the elevator, not buying it and install it as well. That is a stunning admission. They are in basic terms saying that an MRL traction is, give or take, seven grand out of your pocket every year when a hydraulic is only three thousand-seven hundred. That is for the same travel distance and same number of stops. Cost wise hydraulic is the only logical choice. This is especially true when you add in the initial investment cost.
Regarding electricity, the same blog post points out, “In fact, a 2,500 lb. elevator, traveling a single floor (12 feet) at 100 fpm (feet per minute) and operates 100 runs a day, does not even use $600 worth of energy in an entire year. So assuming the hydraulic uses more energy than traction, you could have a differential of perhaps just $150 a year in energy cost.” In other words, in the whole picture, although a hydraulic elevator may use more electricity in a year, it is negligible to say the least.
It is an old canard that hydraulic elevators use significantly more energy than a traction. If it were true, we would produce counter-weighted hydraulic systems. It would be easy enough to do, but who on earth would pay so much up front and then have a more additional maintenance costs of weights and ropes? They make no sense because the electric cost is so low and going down every year as efficiency in hydraulic pumps and motors increase.
This is no old myth. When hydraulic elevator were first installed there were a couple of factors that made them less green than their traction counterparts. The hydraulic fluid used was not bio-degradable and the oil was in a jack underground where leaking could not be effectively monitored. It was a time bomb of sorts as rust and corrosion slowly wore away at the hole lining, jack and bulkhead. The seals were more prone to failure and the drips turned into steady streams of lost fluid.
There are still hundreds of these old systems in place today. And they are either, by some miracle leak free, they are not being routinely checked for oil loss or the person paying the bills would rather buy a five-gallon bucket of oil every quarter than have the jack pulled and replaced.
But things have changed. In many applications you can use above ground jacks and better materials are available when an in ground jack is needed. Generally, PVC filled with sand is in the hole and then the jack is inside the PVC. If installed properly there should be no leaking at all.
Also, the elevator code has recognized the need for improved environmental awareness. If the code is followed, environmental issues should be non-existent to rare. If there are any problems or accidents of an environmental nature it is more than likely due to unqualified installers. Current technology affords jack leak monitoring systems and all the jack components are better than in years past. This coupled with good maintenance and record keeping should significantly reduce any hydraulic fluid escaping into the ground.
But what if it does? Good question. The last line of defense are interceptors for spilled oil that separate the oil from water protecting the environment against leakage. And also you now have the choice of many bio-degradable hydraulic fluids formulated for elevators. Oil replacement and additional testing is necessary so the elevator technician needs to know of this choice. But there is no real need to worry about leaks if you don’t want to with improved rules and technology.
Okay hydraulic elevators are slower. But does that matter? I really could write an entire article on this subject…as a matter of fact I already have. You can check it out here. You can read it if you are really interested, but for everyone else let me cut the the chase. Speed is really needed if you are going over six or seven stories for sure and maybe a wanted convenience you would like going over four or five stories. But for anything below that you are not getting your money’s worth.
The reason is due to limits of the human body and how fast an elevator can get to top speed and still be a comfortable ride. If you are traveling just 30 or so feet you would just barely get to top speed before starting to slow down again for the next stop. Top speed is rarely to never hit in a typical three stop elevator. Think about it, you would be thrown to the floor or pasted to the ceiling if you traveled to top speed any faster. So yes, hydraulic elevators are slower, but for low-rise applications it is not that important at all. Yet everyday we send out Fast Track budget numbers to people that are convinced they need a jet pack for 10′ to 20′ feet of travel. The need for that much speed does not exist.
To increase speed at a lower cost a roped hydraulic is a great option if you are going over three or four stories. It combines a hydraulic system with a pulley wheel at the top of the jack. This speeds up the elevator and increases the total height of travel.
Although limited, hydraulic elevators may go higher than you thought. Two or three stops are just the beginning. I have seen hydraulic elevators installed up to six stops. That is with over 60′ of travel! The chart below shows a comparison of what MEM can provide and associated travel. Keep in mind these are only general numbers.
The important thing is to weigh all the options available and not make any snap decisions without some research. For building owners and managers, that may mean asking some hard questions of your team and comparing costs to benefits. For the architect it may mean thinking outside of the elevator cab. Look for a better technology, before you drop in the same footprint. For the GC you might need to call and ask questions about how other alternatives can make your job easier, not harder when it comes to the elevator installation.
It is important that, when looking at the elevator alternatives, you do not just listen to sales pitches. Doing so will cost you significantly more in both the short and long term. I hope this article makes clear that traction elevators are not a proper alternative for two and three stop projects accept under certain circumstances. Also, hydraulic elevators up to five stories need to be considered. Based on cost and use you may find a hydraulic as the best alternative. Just take a look at the facts, determine your needs, and choose wisely.
You will be keeping your elevator for a long time so seek independent voices. MEM can be a great resource or a qualified elevator consultant. We won’t say one is better than the rest just for a sale. Just find the proper and most applicable mode-of-conveyance for the right application.
If you have a project in mind, or questions about this article or our line of manufactured elevators feel free to contact us for Fast Track budget numbers. Our knowledgeable team will happily advise you on the most effective and beneficial mode-of-conveyance for you and your project. We can provide budgetary numbers in 24 hours.
Elevator Speeds – Everyone wants faster. Many especially are obsessed with a faster car, but that is just the tip of the iceberg. Faster cars. Faster computers. Faster internet. But it really doesn’t work that way with elevators. For most low to mid-rise applications only 100 (for low) to 200 (for mid-rise) feet per minute (fpm) is desirable and for good reason. Any speed above 200 fpm would most likely never be hit in most applications due to stops and starts. So wanting more speed would be just a waste.
To explain further, higher elevator speeds in most hydraulic elevators are never obtained because elevators do not launch like rockets and have to stop in relatively short distances. The rate the elevator takes off at is called the jerk rate (please insert joke here) and how fast it reaches top speed is called acceleration. Acceleration and Jerk (rate of change of acceleration) are human comfort considerations that must be taken into account when looking at elevator speed. The practical limits (for math geeks) are 4 ft/sec^2 acceleration and 8 ft/sec^3 for jerk. If you are a math nerd, or you’re wanting to test out your math skills, this is a good place to start. But take it from me, fastest speeds in most elevators are never reached.
Even at the regular rate of travel between 100 to 200 fpm if the elevator took off too fast the occupants would be thrown to the floor like a character in a Loonie Tunes cartoon. Well…maybe the cartoon is a bit of an exaggeration.
So then if this is pretty common knowledge in the elevator world, why are elevator companies like MEM (Modular Elevator Manufacturing) asked to quote unbelievable rates of travel for even two-story buildings, sometimes five-times the proper speed? Two reasons. One is an honest oversight and the other seemingly more insidious.
Let’s look at honest reasons first. Completed project specifications or spec sheets are filled with tons of information. Like the Dictionary of Architecture & Construction says a specification sheet is, “a written document describing in detail the scope of work, materials to be used, methods of installation, and quality of workmanship for a parcel of work to be placed under contract; usually utilized in conjunction with working (contract) drawings in building construction.” That is a lot of information that has to be captured, updated and controlled.
So when it comes to any building project it is a mammoth effort and elevators are often held separately with elevator providers pulling the info together to be inserted. That means that there is sometimes a lack of direct oversight early in the process regarding the elevator. Also, the desired specs out of need and convenience have been largely copied and pasted from another source.
The other honest mistake is when a company has had several projects of similar height or elevator travel. They feel the specifications can simply be copied and reused. Changes and updates are always meant to be completed, but sometimes the elevator speeds are missed and one or two floors of travel can mean significant changes. These kinds of “whoops” can happen, but the mistake is usually caught somewhere in the process. Countless times we have had to get clarification when the overall speed does not align with the project. We call and the correction is made.
Now for the more insidious reason aspects of specifications are way out of whack regarding elevator speeds. Sometimes when asked for information on pricing, big elevator companies use the opportunity to push certain products and features; right now they are currently promoting traction rather than hydraulic elevators.
A more cynical perspective is that over the long-haul the maintenance of a traction unit is twice to three times more costly and therefore more profitable for them. This can lead to big elevator companies suggesting products that absolutely make no sense. I have personally had conversations with multiple building owners and project managers of two and three-story building projects that were sold on the idea they needed a traction unit for more speed. In reality they needed no more than a simple hydraulic elevator with 200 fpm travel speed. The initial investment of going hydraulic is less and so are the legacy costs of maintenance.
Keep in mind at MEM we produce all types of elevators, so we are not pushing one over another, we just want to make sure that the elevator matches the project. So I guess my old Latin teacher was right “Caveat emptor” ~ Buyer beware. It is as true today as when it was first uttered.
If speed is still a concern, but you are thinking more about the speed of the overall construction process there is only one real choice in elevator that can move your along faster and that is a modular elevator from MEM. Contact Hugo Beltran at firstname.lastname@example.org or call him at 800-755-9359. He would be glad to talk to you about the speed of elevators. For more research on modular elevators click here for our website.