Elevator 101

So. . . you’re thinking of an elevator for your home.  Good idea!

Today, home elevators are no longer considered just for the disabled.  Smart home owners realize that they are extremely functional for the modern lifestyle and are still a relative bargain compared to the rising cost of fuel, food and just about everything.  Then too, the National Home Builders Association has identified elevators as a strategic element of a home, increasing the home value by as much as 10%

Most likely your experience into the obscure world of elevators has been at the office or hotel by simply pushing a button and safely arriving at your destination.  What other mode of transportation can a small child safely operate independently?  As to be expected, elevators are far more complex and highly regulated.

As a potential elevator owner, you need to be aware of some basics, i.e. elevator 101.  The code that regulates the manufacture and installation of elevators is called ASME A17.1 (American Society of Mechanical Engineers)  This document is adopted by individual states with deletions, additions and amendments. Statutory authority is given to various jurisdictions to regulate and inspect elevators.  In the state of California the amended and adopted ASME A17.1 becomes California Code of Regulation Title 8 (CCR T8).  The two state authorities in California that regulate the manufacture and installation of elevators are the State of California and the City of Los Angeles.  With respect to residential elevators, the state exempts residential elevators from inspection, while some cities including Los Angeles do NOT.  Therefore:  when a homeowner lives outside the boundary of Los Angeles, his home elevator may not require an independent 3rd party inspection.  This unique condition makes it incumbent upon the owner, that he or she, has a certain elevator knowledge and deal only with qualified, licensed elevator companies.

When considering your new elevator it is best to determine what type of suspension method you prefer and/or what your particular building conditions warrant.  ASME A17.1 Section 5.3 (residential elevators) provide for 5 suspension methods.  The most common method for residential elevators is roped hydraulic / cable drum and counterweight chain.

Roped Hydraulic: This method is primarily used when a remote power unit location is necessary.  No other system will allow for the location of the “power unit” (power unit consists of motor, control valve, pump and oil reservoir) to be located remotely and not in line with the guide rails of the elevator.

Cable Drum: This method uses a geared machine to turn grooved steel drums that spool hoisting cable onto and off from  the drum, i.e raise and lower.  Advanced engineering design employs elevator controllers that use variable voltage and variable frequency which makes the geared drum machine smooth, step less and quite.  With modern all position mount machines, nearly any building configuration can be accommodated.  Further a geared VFAC machine will Never have a hydraulic leak.

Counterweight Chain: This method uses counterweights to offset the car or “cab” weight, allowing for the use of smaller motors and control drives.  It is imperative that the motor mount in the overhead and in line with the guide rails.  In jurisdictions such as Los Angeles, this method is not permitted.  As with all chain and sprocket, the system will never be as quite and smooth as a cable.

Speed: The maximum allowable speed per ASME A 17.1 Sec 5.3 is 40 Feet Per Minute

Capacity: Capacity is a function of  platform area per code.  Residential elevator design allows for 62.5 lbs of loading per square foot.  A 3’ X 4’ platform or 12 SF equals a capacity of 750 lbs.

Travel: This is the vertical height the elevator serves.  It is limited to 50’

Platform Size: Residential platform size is limited to 15 SF in any configuration.  That is not to say a larger size elevator can not be installed in a home, as it can.  Larger platform size, will change the design criteria for the elevator and generally the building requirements.  This may or may not be of concern to the homeowner and to determine the specific changes, he or she should contact a competent manufacturer versed in the ASME A 17.1 code as well as local requirements.

Car Interior: This is where you, the homeowner can have a say how your elevator will look to its passengers.  Nearly any material can be considered, even glass as long as it is compliant with ANSI Z97.1 code standards.  The only limitation for the interior may be weight as all elevators are weight sensitive but your manufacturer will be able to advise you regarding those issues.  Regardless of the suspension method used or interiors chosen, remember what Henry Ford said . . . .

Hire the experts, it is always cheaper!”