How to decide Specification of Passenger elevator?

This is the Question many face while planning or designing a Building or even during replacing the Elevator. And there are many factors on which the decision can be based we are mentioning a few below which we feel are important from the owners or users point of view.

1. Requirement of Lift Code / Rules and Regulation / Law
2. Type of building and Occupancy
3. Height of the Building
4. What Specification do you get to decide?

Each of the above point is discussed below in details and also other details are mentioned which may or may not be related to the preceding points but are relevant in selecting the right kind of product.

Requirement by the Lift Code / Rules and Regulation / Law

The lift code dictates the type of lifts, its specification (minimum requirments) and sometime even the minimum number of Elevators required for the building. These rules are very important and cannot ignored as most of the countries requires a lift certification to be done prior to handing over the lift for use. Most of the Buildings also require to be certified before occupation and the lift certificate is a Part of requirement for the Building Certification. This means if the lift certificate is not available, the building certification may remain incomplete.

The lift rules may mandate the minimum specification generally depending upon the height of the building and use of the building. For example, building beyond certain height may require two lifts. Some buildings may require a lift for Fire Evacuation. The lift code may also specify the minimum number of passenger, the time from the lowest floor to the top floor, etc.

Most of the elevator Manufacturers will update their products based on the local requirements however, some manufacturers do not update some products so it is best to check and verify to ensure that the Lift and the building codes are conformed to before freezing the specification.

Type of Building and Occupancy

After meeting the lift and building codes, The type of building and its occupancy is important for ensuring smooth traffic flow within the building. This defines not only specification but also other details like backup power, Access Control for floors, etc.

Commercial Skyscrapers have traffic peaks during the morning and the evening hours due to people coming in and leaving during start and end of office hours. This might Require multiple High Speed Elevators having larger carrying capacity with destination dispatch technology which directs the passengers to the right elevator based on the destination floor of the passenger. These Elevators are also setup for Up Peak and down Peak traffics so that during the up peak time the elevators automatically return to the Lobby Floor ready to carry more Passengers to the upper floors.

A Residential Skyscraper having only one unit per floor will have lower traffic than the commercial building and may require a smaller carrying capacity with Group Control where the nearest elevator attends when a call button is used by the passenger. These factors are important to make right decisions as specifications determine the cost of the Product.

Some Elevator Companies will provide a clear traffic analysis for the building building based on the inputs provided by the owner of that building. These traffic analysis help understand the traffic flow and thereby help make a decision on which product to purchase.

Height of the Building

Height of the building is clearly a simple and an obvious factor influencing the speed and the carrying capacity of the Building. The Speed of the Elevator must be so that it does not create ques for the lift and also should not be carrying single passengers. The Speed has to be right to create a Que to fill up about half of the elevator carrying capacity during the peak hours in the peak direction. This saves on the the number of trips and hence power consumption.

Similarly, the carrying capacity has to be determined to ensure that the carrying capacity is not more than required or less than required. Higher carrying capacity means more power Consumption every time the lift moves even if the lift is hardly occupied.

For Speed, for mid and high rise buildings, I recommend using a Standard of 35 to 45 Seconds of travel, this means you can Select a Speed based on the fact that the lift must travel to the top from the lowest floor within 35 or 45 Seconds. 35 Seconds for Medium and High Occupancy Buildings and 45 Seconds for Low and Medium Occupancy Buildings. For Low Rise Buildings with low traffic, 30 Seconds is about right can be used to travel from lowest to top floor. However, I also recommend using a lift with minimum of 1.00 Mps for any Building, except for home or villa elevators.

What Specifications do you really get to decide?

Generally, a owner of the building will employ a third party consultant who may be well versed with deciding the specification of the elevator. But most of the time the specification of the elevator is presented to the owner or consultant by the various elevator manufacturers as a part of the solution based on project needs. This being said, the owner does have choices within what is present to him and also beyond. The choices within the solution may be the interiors of the Elevator, the Type of Door – Center or Side opening (if technically feasible), The Speed of the Elevator depending on the speed ranges within the model of that elevator, Some non mandatory features to be included or excluded, etc.

Beyond the Presentation the Owner may have his own specification which can be shared with the manufacturer and the manufacturer can offer a price based on that specification.

Below is a List of Specification which a buyer may put forth the Manufacturer at least to have before him a comparative for evaluation

1. Speed of the Lift
2. Carrying capacity
3. Door Opening Width – At least Enough Width to move Wheel Chair and if possible Stretcher / Hospital Bed.
4. Control Type – Closed Loop or Open Loop – Closed Loop is Preferable
5. Fire Switch, Fire Mans Switch and Fire Modes – to be included or no – Preferable to be included
6. Load Weighing Device – to be included or no – Preferable to be included – prevents overloading
7. Simplex or Duplex or Group Control in case of two or more lifts – Duplex or Group control is preferable with Separate call buttons for each Lift
8. Door with Fire Rating or No Fire Rating – Preferred to have Fire Rating
9. Auto rescue device – Preferred and sometime required by Lift Codes for safe evacuation in case of Power Outage
10. Interiors of the Cabin – Walls, Flooring, Ceiling, Door type (Glass Doors, Steel Doors, Painted Doors), etc – Choose based on Budget
11. Motor Type (Few may offer this Option) – Geared Machine or Gearless Machine – Gearless Machine is Preferred.
12. Access Control – Generally offered in premium residential Buildings – Ensure full availability during emergencies without the access Cards
13. Earthquake / Seismic Sensors / Detectors – Preferred to be included
14. CCTV Camera System – Preferred to be included
15. Telephone / Intercom System – Preferred to be included with separate battery in case of Power Failure

The above list is comprehensive and may not include all the options but it is a simplistic list which you can put before the manufacturer to ask for the options to be listed or to check if they have been included in the elevator.