Generac Power Systems Inc. said Tuesday it's spending $8 million to $10 million to expand and remodel its headquarters, in Waukesha WI, and to create a technical center.

Generac said it employs more than 550 people at its headquarters, and plans to add more than 200 jobs over the next three years. Generac makes residential, commercial and industrial generators.

The expansion and remodeling is expected to be completed by the end of 2013, the company said.

Generac said it has purchased land adjacent to its headquarters for future expansion.