International Game Technology expects to complete a 124,000-squarefoot expansion of its Reno headquarters this autumn.
Clark & Sullivan Constructors of Sparks is the general contractor on the project.
The work will add 225 feet to the south end of IGT's building on Prototype Drive in South Meadows.
The two-story addition 62,000 square feet on each floor will bring the total space in the building to 1.1 million square feet.
The space will be used for offices rather than manufacturing, said IGT spokesman Rick Sorenson.
The company hasn't designated which departments will move into the new space.
Sorenson said the construction is dictated by growth of the company, which dominates the market for slot machines and other gaming devices.
IGT, the largest manufacturer in Nevada, sold 91,500 machines worldwide from its Reno plant during the six months March 31.
That marks rapid growth from the 64,500 machines sold in the same period a year earlier.
The company moved into the south- Reno headquarters and manufacturing facility in 1996.
