Somebody is always mad about historic review.

One day it's a developer whose project the Historic Review Commission rejected, the next an opponent of a developer whose project the commission approved. Not infrequently, it's an adherent of historic review, angry that the commission approved a demolition, or a roof deck.

Two recent cases show the complexities of the process, and how the efforts to do what's best for the property, the neighborhood and the owner can end up leaving everyone a little frustrated.

Over the years, Pittsburgh City Council has designated all of Manchester and parts of 11 neighborhoods historic districts, ramping up standards, property values and scrutiny.

It requires that property owners apply to the Planning Department for approval to change almost any exterior feature of a building -- windows, doors, stoops, porches, paint color, materials and lighting.

Preservation planner Angelique Bamberg may permit repairs and many alterations, but she passes to the commission proposals for construction, demolition and removal of historic materials, such as replacing wood windows with aluminum or vinyl ones.

The city established the commission in 1979. Its decisions can be appealed only to Common Pleas Court, said planning Director Pat Ford, who sits on the commission. The planning director and the head of the Bureau of Building Inspection are perennial members. The mayor appoints the others, who currently include four architects and a Realtor. The guidelines are those of the U.S. Department of the Interior, and they affect 12 parts of the city.

Four are on the North Side -- Allegheny West, Deutschtown, Manchester and the Mexican War Streets. Three are in Oakland -- Oakland's civic center, Oakland Square and Schenley Farms. Two are Downtown -- Market Square and an area anchored by Penn and Liberty Avenues, roughly between 7th and 10th streets. The others are East Liberty's Alpha Terrace, the South Side's East Carson Street and Squirrel Hill's Murray Hill Avenue.

Each district's resident committee forwards recommendations to Ms. Bamberg. Between rigid adherence and wholly unacceptable alteration, there are ways to bend and not be offensive, she said. Even the rule of thumb can be bent (as we'll see in the case of the pergola). The rule, basically, is that anything visible from a public right-of-way must undergo review, she said. An alley is a public right-of-way, but there is more tolerance for utilitarian changes in the back of a house, such as aluminum windows, she said.

Greg Mucha has spent 12 years on his neighborhood committee, holding his Mexican War Streets neighbors to standards he believes should not become too flexible. He's been known to stop people in mid-project. He encountered one neighbor installing aluminum windows and told him the windows wouldn't pass muster. The man spit nails and gave him what-for and asked him who he thought he was.

"I tell people, 'You live in this neighborhood, you have responsibilities,' " said Mr. Mucha.

To Bob Russ, an architect who serves on the South Side's East Carson committee, the responsibility is to "community good over the individual, but hopefully it comes back to the [benefit of the] individual."

That "community good" results from a loose consensus that historic aesthetics create sense of place and strength of place, both obviously worth nurturing. Mr. Russ makes that case for East Carson Street's wild success.

"A lot of new businesses don't understand the historic context and see us as design Nazis. They think the place was successful first. It's successful because of many things but one is historic guidelines. Preserving East Carson makes it more valuable."

He and his review colleagues are coming off a disappointing loss at the August commission hearing -- 2312 E. Carson St.

"We consider it a contributing building," said Mr. Russ of a two-story with a neo-Dutch-colonial facade and a profile reminiscent of the outline of a barn. "Contributing" means it represents a style of architecture the district is trying to preserve. Most of East Carson is 19th century Victorian-era buildings. Mr. Russ judged the facade to be from the '20s or '30s. But the committee saw something in its oddity to make it worthy in the mosaic of East Carson architecture.

The commission disagreed and voted to allow demolition so that Cupka's Cafe II can expand. That approval came with conditions that the design be altered, however. Mr. Russ said property owners in the past have gotten away with designs that short-cut the agreed-upon alterations, against which the HRC usually didn't press the issue.

"New owners who are either ignorant of the rules or callously disregard them, break them and then we have to play catch-up," said Mr. Russ. "Word on the street is that the HRC is lax and loose with their own rules. The core of the guidelines has case law behind it."

"There are too many inconsistencies," said Mr. Mucha. "They allowed a window within a window, which we would never recommend. It's not historic."

Mr. Ford, who administers the HRC and four other boards and commissions, said the commission considers the historic worthiness in context. "We cannot review with blinders on," he said.

He said a building should be judged not just by age or style but by the role it performed historically and whether it holds up in the context of both its time and today. "How does the community view it? Does it reflect [well] on the identity and the culture of a place? If it doesn't, what are we saving it for?" Additionally, he said, "We shouldn't be worried about paint colors or materials as much as whether it fits and how it reflects on the buildings around it."

Because downright rigidity does not serve the road to progress, he said, the commission considers every case on a case-by-case basis.

This scenario, which makes purists so uneasy, favored Dave Solosko and Sandy Kniess last fall. They had just moved from Marshall into the home they spent a year refurbishing in the Mexican War Streets. During the work, said Mr. Solosko, "the foreman was at the house when someone knocked and asked if there was a permit for the pergola" on the roof-top deck.

Mr. Mucha said it was he. "It didn't go before the review board," he said. "I asked Angelique, 'Did you approve that?' and she said no. So it was brought before the local committee, and I don't think we recommended it."

"It turns out there was a permit to replace the deck," said Mr. Solosko, "but nothing specifically about the pergola. The architect had seen other pergolas in the neighborhood and didn't think it was a problem."

Visible from the alley, the pergola at that point had been claimed and enwrapped by clematis.

A decision was postponed at the August hearing. When the HRC reconvened a month or two later, half a dozen neighbors turned out to support Mr. Solosko and Ms. Kniess, whom they barely knew.

"That was what was so astonishing," said Mr. Solosko, " and I think it was due in large part to the support we got from our neighbors that they voted unanimously to allow it."