The next phase of an ambitious multiyear plan to conserve and preserve Constantino Brumidi’s famous frescos that gets under way next month will yield a special treat for the public.

The Zodiac Corridor, which features all of the astrological signs painted along the ceiling of one passageway, has been used as office space for Senate appropriators and staff since 2003. Upon the completion of conservation work, which could take up to 10 months, the door will be taken down.

Currently the door to the makeshift office space is topped with a Plexiglas window so viewers can get a glimpse of the paintings on the ceilings of the corridor.

“The Senate is going to let us conserve all the murals in there and open it back up,” Capitol Curator Barbara Wolanin said. “It’s going to take a while. You have to go over every square inch, every little spot.”

The effort is an important next step for historians and art conservators who, above all else, want to restore the intricate artistry on the walls and ceilings of the Brumidi corridors to their former glory.

The other area set for restoration in August is the “Trophy Room,” the area immediately past the Senate appointments desk en route to the House side of the Capitol.

Having completed work on the ceiling decorations in previous years, conservators will now be focusing on returning the wall panels to the original intended colors: much brighter hues than the murkier tones of today.

From 1855 until his death in 1880, Brumidi painted some of his most famous works in rooms throughout the Capitol and on the Dome of the Rotunda. Known as the “Artist of the Capitol,” Brumidi also oversaw a team in conceiving of and painting in fresco many portions of the corridors that run throughout the first floor of the Senate wing of the Capitol.

Decorated with ornate patterns of scrolls, flowers, angels and woodland creatures, as well as historical and allegorical scenes in the areas above office doorways, the hallways were inspired by Raphael’s loggia in the Vatican.

Brumidi was born in Italy in 1805 — Thursday would have been his 207th birthday.

Wolanin, who has written a book about Brumidi and his work in the Capitol, said conservators have identified layers of color and detail buried over the years.

Eventually, conservators will enter the phase of restoration in which many of the Brumidi corridor wall panels, now brown, will be returned to buttery yellow. The ceilings, now that same buttery yellow, will be toned down to ivory.

“Conservators started to find out there were these beautiful colors — whites, not golds,” Wolanin said. “What happened was that everything got dirty, and when someone would come along to repaint, they’d repaint to match the dirt, match the colors that were there. … There was no such thing as a fine-art conservator then.”