It's an old joke: If a farmer keeps his barn full, he gets mice; if he leaves it empty, he gets actors.

Alyssa Cwanger, Post-Gazette Co-artistic directors Corey Rieger, left, and Mark Clayton Southers work to reinstall the dressing room mirror from the old Penn Theatre in their new space Downtown. Click photo for larger image. 'The Butter and Egg Man' Where: Pittsburgh Playwrights Theatre Company in Jackman Building, 526 Penn Ave., Downtown (entrance between Starbucks and Subway). When: Through Jan. 30; Thurs.-Sat. 8 p.m.; Sun. 2 p.m.; also Jan. 30 at 7 p.m. Tickets: $15 in advance; $20 at door; $15 students; $75 season passes (five plays); 412-441-2213.

F or the urban version, there's the Pittsburgh Cultural Trust's lease on part of the Jackman Building, the parking garage on Penn around the corner from the front of Heinz Hall. The theatrical mice in there have included Quantum Theatre's "Closer" in 2003 and a big Flux party last June.

But the newest tenant, Pittsburgh Playwrights Theatre Company, may have come to stay. Its lease is temporary, but the young company is already such an addition to the city and a needed plus in the Cultural District mix that, if the space works, the Trust would be foolish not to keep it.

PPWT is hands-on and grass-roots, led by Mark Clayton Southers, who founded the then-predominantly black group two years ago when he took over the Penn Theatre in Bloomfield-Garfield. A fall change in the building's ownership led to a sudden rise in rent, which made Southers susceptible to the invitation from the Trust to move Downtown.

The new space opens tonight with "The Butter and Egg Man," a 1925 comedy by the most famous, prolific Pittsburgh playwright, George S. Kaufman. Fittingly, it's about a couple of producers trying to put on a play.

"We're coming out of the gate with a fast-paced comedy," says Southers. Subsequent plays will be by active Pittsburgh playwrights, members of the group, but PPWT has also identified itself with the other greatest Pittsburgh playwright -- August Wilson, with whose "Ma Rainey's Black Bottom" the company first made its mark two years ago.

"We can go on forever doing Pittsburgh playwrights' plays," Southers said.

DO-IT-YOURSELF

Last week, while director Jane Lane rehearsed "Butter and Egg Man" elsewhere, Southers, co-artistic director Corey Rieger and other PPWT volunteers were hard at work sawing, hammering, painting and otherwise inventing a theater space in which to stage the plays that playwrights invent.

This urban homesteading made an inspiring scene: a huge concrete expanse, tucked in between street-level shops and parking garage above, littered with drills and hammers, buckets of paint and lumber akimbo. Coming through the door one flight up from Penn, you're in the main space, roughly 75 by 80 feet, with high ceilings, largely free of pillars, plus a huge additional alcove with sloping ceiling.

Southers pointed out the planned lobby by the windows above Penn, with the stage across the way; a box office here and technical booth there; two bathrooms.

The theater is compact, roughly 45-foot-square, with a 25 by 25 thrust stage and 74 seats -- and the company already plans to stage its second show in a proscenium arrangement and its third, in the round.

PPWT is doing most of the work itself, so the most valuable members are those with construction skills. The Trust knew what it was doing when it pursued the company. Prime Stage is already in the Cultural District, but other small groups interested in moving expected the Trust to create spaces for them; PPWT was willing to adapt a raw space itself. It takes its work ethic from Southers, a steelworker turned playwright and entrepreneur who knows that to get something done, you do it yourself and inveigle others into pitching in.

Beyond the main space is another room, larger still at 75 x110, formerly occupied by the Art Institute. Now, it's littered with everything PPWT brought from its previous home -- furniture, chairs, lockers, fence units (from "Fences"), even a coffin. The room includes two platformed areas, which serve for rehearsal, plus a hodgepodge of sofas, a sort of club room.

That's a key to PPWT's style. In just two years, Southers has gotten a lot of actors and playwrights to jettison wait-and-see for active participation. "Good actors are a magnet" for playwrights, he knows. But so is a place where everyone is welcome. A place to relax among the hustle-bustle helps.

PPWT is buying its supplies itself, although there is a $10,000 grant coming from the Pittsburgh Foundation. "We don't squirrel money away," Southers says. "We go month to month." Actors have been paid from the start, albeit sometimes very little. "We want to do quality shows, give actors and directors a shot, give audiences a Downtown alternative, and build toward paying salaries."

Southers cites the helpfulness of the Trust's Janice Burley Wilson, Rebecca White and David DeSimone. But the work is PPWT's, and they notice the details: all those sandwich shops where the PPWT team has been buying lunches will be hit up for ads in the program.

THE AGENDA

In sponsoring PPWT, the Trust gets more than do-it-yourselfers. It also gets black theater. But Southers is quick to redress the perception that PPWT is all black: "We don't do white theater or black theater; we just do theater."

He's not as naive as that sounds. He knows that "white theater is like a wall, with few roles for blacks," but the reverse is also true, and he blames the plays that are available. Hence PPWT's Theatre Festival in Black & White, split evenly between black and white playwrights, with white playwrights assigned black directors and vice versa.

If this goes against his mentor, August Wilson's stance that black directors should direct black plays, so be it. Southers himself directed "Dorothy Six," about white steelworkers. He isn't white, "but I'm a steelworker." His goal is simple, "not so much to tear down walls as to get black and white actors to work together. It all comes down to what's written for people to do."

One working on the new space is Mark Thompson, a white actor, director and movement teacher but, more to the point right now, a carpenter. "Given my values," he says, "this is the most important theater initiative in town, because of its inclusiveness."

It took him a while to get involved. "All I knew was a Post-Gazette article about [Southers] and his connection to August Wilson. I wondered about the cultural politics -- would I fit in?" But when he looked in at the Penn Theatre, "it looked to me they were having more fun than anyone else." He won a best actor award in this year's Black & White Festival. Now he's pounding nails.

So is actor Alonzo Green, who won a best actor award in a previous festival. "If we give you best actor, you have to serve us for three years," Southers jokes. "'Give'? I earned it!" says Green. He's known Southers for a couple of decades.

Rieger, who graduated with a degree in drama from Allegheny College in 2003, got involved in the first Black & White Festival. Now he shares the artistic directorship. "I feel restless if I'm just acting," he says.

Thompson says "people have responded to the vigor of the two festivals" -- not just Black & White, but also Pittsburgh Pride, a festival of gay plays.

"We want true-blooded theater folks to get involved," Southers says, looking past tonight's opening. "I think we've done some good work, without being around for very long, but we definitely have our quality gauge turned up higher now."