MERRIMACK — New Hampshire-based hotel owner/operators Roedel Cos. broke ground on a multimillion-dollar renovation of the former Fairfield Inn on Amherst Street that will convert it into a Holiday Inn Express & Suites hotel.

Roedel said the property will be transformed “to better suit the needs of today's business travelers and include 100 guestrooms and expanded business center.”

The hotel is slated to open in September, off Exit 11 of the Everett Turnpike.

Roedel Cos. (www.roedelcompanies.com) subsidiaries — ROK Builders and RGH Hospitality — will renovate and manage, respectively, the new Holiday Inn, the company said in a news release.