Method and arrangement for installing an elevator

An elevator, comprising:

• an elevator car configured to run in an elevator shaft along a plurality of guide rails;
• a balancing weight connected to the elevator car with a suspension rope extending through an upper part of the elevator shaft above the elevator car and further connected to the elevator car via a traction member extending through a lower part of the elevator shaft below the elevator car;
• hoisting machinery including a driving wheel in the lower part of the elevator shaft below the elevator car;
• a first supply reel configured to supply additional suspension rope to extend the suspension rope, the first supply reel secured on a roof of the elevator car;
• and
• a second supply reel configured to supply additional traction member to extend the traction member, the second supply reel secured on a lower part of one element of the balancing weight or the elevator car, such that the second supply reel is configured to have no relative motion in relation to the one element when the one element is in motion in relation to the elevator shaft,
• wherein the elevator is configured to be extended to enable the elevator car to run through a higher portion of the elevator shaft to serve one or more higher floors, based on the suspension rope and the traction member each being extended.