Valley Medical Center is planning on a major expansion project that will add a seven-story parking garage and five-story medical office building to the hospital’s Renton campus in the next few years.

The office building is planned to be a comprehensive cancer treatment center, designed to bring together all of the hospital’s cancer treatment facilities.

According to Valley Medical Vice President of Facilities Todd Thomas, the new garage will be built first with an expected completion by the end of next year, with the new office building to follow.

“We’ve kind of outgrown the current facilities available on campus,” Thomas said this week.

Thomas said the hospital has had a long term need to combine all of its cancer treatment services, which are spread across the campus.

“It just allows us to better and more effectively serve our patient population who have those needs,” Thomas said.

While the hospital would build the garage at an estimated cost of about $25 million to $28 million, the plan is for the new, 160,000-square-foot office building to be built and owned by Healthcare Realty Trust, with Valley owning the land underneath and leasing space. Thomas said there would be the cancer services on the first and third floors, while the second floor is being designed to house a new orthopedic and ambulatory surgery center. Thomas said out-patient orthopedic services are the “way the industry is moving” and medical journals predict that 50 percent of orthopedic services in the near future will become outpatient services, as opposed to those requiring a stay at the hospital.

The other two floors in the medical office building would be leased out by the Realty Trust.

Thomas said additional plans include elevated walkways from the garage to the medical office building, as well as a connection to the hospital through a tunnel.

Because the new garage will be built on existing parking spaces, Thomas said the plan is to open the first floor as soon as possible, even while construction continues on the upper floors.

Bids for the garage were scheduled to be opened today, Friday, with construction to hopefully begin by the beginning of the year. The office building is still in the design and permit phase and there is no timeline yet for its construction.