Home Elevator Hoistway Shaft
If you have the impression that putting an elevator shaft in your home is as simple as cutting a hole in the floor, think again. A typical home elevator hoistway consists of two or more fairly large closets, stacked one per level, with the floor/ceiling layer between them removed. Some designs also require a machine room (see below) about the same size as one of the closets. Most home structures need little to no additional reinforcement to support an elevator, apart from two vertical columns running top to bottom on one side of the shaft interior. For most home elevator designs, a “pit” of 6 to 14 inches is also required below the lowest level, and additional headroom (extending into the attic) may be required above the top for the shaft.
Home elevator shaft dimensions
How much floor space is needed for a home elevator? According to American building codes, no home elevator cab can be larger than 18 square feet on its interior. Generally, a shaft 5 feet square is sufficient to hold this largest permitted size of elevator cab. In very small homes where not even 25 square feet per floor can be spared, a smaller cab is sometimes used.
Machine room requirements for home elevators
A machine room may or may not be needed for your home elevator depending on the drive type you select. Hydraulic systems do require a machine room, usually about 5 feet square (about the same size as the shaft itself),
in the general vicinity of the elevator installation. Cable winding drum elevators require a similarly sized machine room, positioned adjacent to the topmost section of the hoistway.
Chain drive and inline gear drive elevators do not require a separate machine room, making use of attic space instead. This is one of the chief benefits of chain drive: It takes up less usable space in your home.
Exterior shaft doors
An elevator system has both gates and doors. The gates are the accordion-fold barriers which are built into the cab and prevent the occupants from falling out while the elevator is in motion. The hoistway doors are built into the side of the shaft, and are designed to keep people from falling into the shaft from the outside, or sticking anything in the way of the elevator.
In themselves, exterior shaft doors for a home elevator are nothing special – they’re pretty much just solid-core interior doors (as opposed to the common hollow-core variety), and can usually be supplied by your builder. A home elevator contractor will add special electro-mechanical interlock latches to the exterior shaft doors when the elevator is installed. These ensure that the elevator will not operate while any of the exterior doors are open, and similarly, that no exterior door can be opened unless the elevator cab is present and stationary at that floor. These measures are required for any safe residential elevator installation.
Construction cost of a home elevator hoistway shaft
If you are building a new house, the cost to add a home elevator hoistway is minimal – indeed, negligible – in most cases. As outlined above, there’s nothing particularly special about a home elevator shaft; it is simply two or more closets directly on top of one another in the plans. In fact, it’s a great idea to plan such closets into any new home, even if you don’t intend to add a home elevator immediately. The closets will remain fully usable until the time comes when an elevator needs to be installed; then, these closets can be converted into an elevator shaft by simply sawing a hole in the floor and reinforcing the inside wall with planks.