BATH — For the first time in 20 years, the Patten Free Library is expanding, and for the first time in its history, there will be a dedicated space for teens.

Construction began earlier this month on the project — which will cost more than $330,000 when fully completed — and should be completed by the end of the summer. The library has raised $311,000 and is still trying to raise an additional $20,000 for the project.

The new space will be fully enclosed with new glass walls in a large back corner of the nonfiction area. The room will have a nautical theme, and there will be a raised seating area and audio and video equipment, said Lesley Dolinger, the library’s director.

There will be multiple charging stations, folding tables and chairs and the young adult collection will move into the new teen space.

The current teen space has donated furniture that is falling apart, and it’s not enclosed and it’s small. Because of the size, there’s not much room for collaborative activity.

In 2012, the library’s board approved a new strategic plan, and teen services was one of the areas the plan identified as needing to be addressed, Dolinger said. It stated that providing an adequate space and programming for teens was a priority.

“We feel we have such a strong children’s room and robust adult programming, but we didn’t offer a lot in our teen space, which was a very small alcove off the reference area,” Dolinger said. “It’s not really conducive to anything that teens want to do.”

The strategic plan also charged library staff with attracting more teens to the library, which is an increasing challenge with so much technology and other things for teenagers to do.

The teens that come to the Patten Free Library come to use the high speed, fiber-optic internet, work individually or in groups, check out books or just socialize, Dolinger said.

“Teens have been coming in more after school and we’ve been offering more programs,” Dolinger said. “So we’re attracting (teens), but we just didn’t have the right space.”

In the last several years, the library has been devoting more resources to staffing, programming and collections, and the last piece of the strategic puzzle was creating the new teen space.

After the development of the new strategic plan, a committee was formed, which included teen library council members, that met for months and worked with architects to design new space.

“We didn’t know how long (construction) would take, because it has been so long since any construction projects or renovations,” Dolinger said. “We’re using all private donations and grants.”

In addition to the teen space, Dolinger said there was a great need at the library for a group study room for tutoring, one-on-one instruction and small group activities. She said everyone at the library is excited about the new room.

Part of the project also includes replacing furniture with new tables and chairs outside the teen space, an area with large windows that look out on the Kennebec River and Sagadahoc Bridge.

Dolinger said the work is being called the Teen Reference Space Renovation Project because of all the additional work being done aside from just the new teen area, including the modernization of the reference desk.

The board decided to allow construction to begin without the project being fully funded, Dolinger said, because waiting until the library had all the money would delay the project even further.

“If we have to pay ourselves back, we will, because we’re moving forward with the project,” she said. “We’ve raised most of the money and we’re confident we’ll raise the rest.”

The library, at 33 Summer St., was founded in 1847 and the current building was constructed in 1889; new wings were added in 1961 and 1998. The library serves Bath and the neighboring communities of Arrowsic, Georgetown, West Bath, and Woolwich.

Dolinger said library patrons will have to be patient and understanding during the 12- to 14-week construction period. There will be noise and some disturbances and minor inconveniences, but Dolinger hopes the library’s users see how much the project will help the library in the long run.

The reference desk will be closed throughout the renovation, and the library’s public computers have been relocated to the reading room.

Everyone is pretty excited about the project and is eager to see its completion, Dolinger said. There have been complaints in the past about the noise teens were making in their current space, so this project will alleviate those concerns.

“And we’re going to have air conditioning in that teen space, and I want everyone to know that,” Dolinger said. “In the summer, it’ll be a place for people, not just teens, to get cool.”

The space, while being built for teenagers, will also be used by book clubs and will be accessible to the general public at times when teenagers aren’t around, especially during the school day. Dolinger said it wasn’t realistic to have a room solely for teens, because there is so much of the day where they can’t use it.

“But it’s their space and we want them to feel like it’s their space,” Dolinger said. “We want it to be a versatile space, especially because (teenagers) are very spontaneous.”

It’s been more than 20 years since the last expansion of the library, and it’s time for new excitement and energy, Dolinger said.

“It’s going to benefit everybody,” she said. “We’re going to have beautiful new spaces and we’re very excited.”