Car Lift at GAS (General Automotive Service of NTUC)
Two of these lifts were installed at GAS. The picture shows one lift before the walls were put up.

Originally, the lifts were for transferring cars to the 2nd level for storage, i.e. low usage of about 20 cars per day maximum. The building was bought over by NTUC Taxi for servicing taxis on the 2nd level. Now traffic is continuous, more than 10 hours per day.

NTUC agreed the lifts were not meant for such duty and were prepared to up-grade the duty as breakdown occurred. Eventually the all chain sprocket bearings, at the top and at the hydraulic cylinders, had to be up-graded. (We used vesconite bearings x4 safety factor, so far so good).

Powered doors were installed later because manual doors tend to be left opened. The doors came in 3 modules, the left, right and the door itself. Two doors per lift, one at the lower floor and one at the top. Installation needed only two days.

The picture on the left shows the two lifts at the first floor. Doors at the 2nd level are exactly the same.

A geared motor turn a shaft which can be seen above the door at the right of the picture. At either ends of the shaft are chain sprockets. The doors are lifted up by the chains.

Each chain started at the top of a counter weight and ended at it's bottom. The counter weight is to assist manual operation of the door. 
The above one piece door needed a lot of headroom. We could design a more compact 2-stage telescopic door.