Construction Construction Key The Construction Key concept is as simple as it is clever. During construction work, access to all apartments is available to different workmen using a single key model to open and close all doors. Upon delivery of the apartments to customers, however, each apartment receives its own access code. How is this done? During construction, the contractor conveniently controls all locks on the site with a single key – without the need to either carry numerous keys or install a master key system. Then, when handing the property over to its new owner, the contractor uses a special Change Key, which switches the cylinder from its “contractor mode” to the “tenant mode”. From now on, only the specific keys, which the owner receives in a sealed envelope, fit the lock. Through our network of selling units, distributors and retail partners, you can learn more about this and other solutions, receive expert advice and custom solutions.