JoAnn Phillips’ eyes scan the M Streets Tudor she spent six months renovating. She jokes that it was a “mercy mission.” The house, inhabited by a friend, had a collapsing garage, a completely overgrown driveway, a roof needing repairs and a faulty foundation, not to mention required a new air-conditioning system, electrical wiring and plumbing.

But if she hadn’t fixed it up, Phillips says, someone else would have come along and scraped it. And judging from the way she coos over the façade’s “mushroom” archways and the front window’s original stained glass, Phillips was not about to let that happen.

“I would never have torn this house down, and I could’ve,” she says. “I’m a licensed builder. I could’ve torn this down and made $150,000 more.”

That’s what someone else plans to do with the Tudor next door, Phillips says. She tried to save it, too, but lost the house in a bidding war to another builder.

“And he’s going to go and maximize the square footage and take up the whole lot,” she says, with evident disdain in her voice.

Phillips isn’t the only builder with this view. A handful of others are opting to salvage the houses that line our streets rather than demolish them and start from scratch. It’s usually a less lucrative option, but money isn’t the only factor when a builder decides to take this approach. Instead, it’s because they love old architecture, or because they relish the challenge of extracting the beauty from an existing structure.

As Phillips says: “You do it because you like doing it.”

That’s exactly what led Nancy Bowen to purchase her first remodel project in the mid-’80s. For years, she purchased and renovated one home after another, many of them in the White Rock Lake Peninsula neighborhood where she lives (in one of her own projects, of course). It wasn’t unusual to find Bowen rummaging through junkyards to find claw-foot tubs and antique window sashes, anything that would reflect the period in which the homes were built.

The highest compliment anyone could pay her is to ask whether something she changed or added was original to the home — a sentiment echoed by other builders who take this approach.

Lately, however, “this knock-down business,” as she calls it, has changed the market and caused Bowen to spend more time donning her other hat, that of real estate broker. She even relinquished a house on her own street to a builder who plans to tear it down and build something she considers an eyesore, and she did it for one reason — cost.

“I thought, ‘You know what, it’s not worth losing my shirt on,’” Bowen says. “It’s just so hard to buy these houses at such a high price and then they need everything.”

The other dilemma for people such as Bowen is that today’s buyers want more space, and quaint older homes with 1,700 or so square feet don’t have enough to suit them. That’s one reason why neighbors such as Laura Elia, an interior designer, hunt for duplexes they can convert to single-family homes.

“The footprint is already there, so you don’t really have to change the exterior very much,” Elia says. “Many of them have those great porches, and the architectural lines of the house are so appealing.”

After taking out a few walls, Elia usually has around 3,000 square feet to work with. Her most recent project, a house on the corner of Skillman and Velasco in Lakewood Heights, was nicknamed “the puffy house” or “the smurf house” by her friends because of its rolled Swiss roof. Elia redid the roof but otherwise left the 1930s Tudor exterior pretty much intact. Then she gave the interior a more contemporary feel in an attempt to cater to a younger crowd, she says.

Whether they are working to reflect a home’s original style or giving its rooms a complete makeover, every builder interviewed made clear that buyers would pass over a house lacking modern conveniences. And even with the stainless steel kitchen appliances and cascade showerheads, these homes can lose money more easily than new builds because remodelers must deal with the unexpected challenges that inevitably accompany older homes.

“It’s not like you want to just put a band-aid over it — you want to fix it to the bones and really restore it,” she says. “But the [profit] margins on it are much smaller, so you really do have to have a love for it and a passion to do it.”

It’s not that these builders are hurting financially. Remodeling historic homes increases their value significantly — the appraisal of the Tudor Phillips restored jumped from $229,000 to $400,000 once she finished the job, and Bowen even argues that some buyers are willing to pay a little more for an updated historic home. However, there’s no escaping the major factor driving the residential real estate market — price per square foot.

Cody Acree and his wife, Kelly, make up development group CGA Properties and know this all too well. They estimate it costs 50 percent more and takes two to three times longer to remodel an historic home rather than knock it down and start over.

“Because it’s not cookie cutter. You labor over every decision,” Acree says. “You can’t do 100 of these a year — you do half as many [as teardown builders], and they have to be perfect.”

But more time plus more money invested usually doesn’t equal a higher price tag. In fact, Acree says that some of their homes are listed for less per square foot than nearby new builds. One of those is a 1940s duplex on Goodwin that the Acrees converted into a single-family home. To reflect its period, they hand-scraped the oak hardwoods and installed antique vanities in the bathrooms, but they also updated it with a media room, complete with projection screen and theater seating. Yet the house, which went on the market in 2005, still hasn’t sold.

The Acrees have remodeled homes in Hollywood Heights and Munger Place, both historic districts, where tearing down homes is illegal and builders must adhere to strict guidelines. Homes in these areas tend to be snapped up fairly quickly, Acree says.

“But in the areas where they’re given the option, like the M Streets or south in the Vickery Place area, it seems as if those buyers are more predisposed to the new car smell as opposed to the character of the home,” he says.

Whenever the Acrees finish a project, they hold a preview party and invite surrounding neighbors to tour the home. Most neighbors are grateful the house was spared, Acree says. He remembers one woman in particular praising their work and in the same breath giving a tongue lashing to a company known for scraping homes and building so-called “McMansions” in the neighborhood — until Acree stopped her short by asking: “Didn’t you just sell your home to that company?”

That’s one of the challenges in their line of work, the Acrees say. They come in contact with dozens of neighbors who support the preservation of historic homes, but when it comes down to selling their own houses, the sale goes to the highest bidder — even if it’s a teardown builder.

“We’re bidding against people who are likely to scrape the house, and the homeowners have to look at who they want to be selling the house to,” says Kelly Acree. “These neighbors can play a role in saving these houses from that perspective.”

Bowen recently saw this happen with a woman who lived in the Peninsula neighborhood. She passed on an offer from a builder and instead sold the house at a lower price to someone who wanted to live in it.

“She had built it, and she did not want to see it torn down,” Bowen says.

But the woman’s decision was the exception, not the rule, Bowen says. Even if sellers want to pass up the highest offer, she says, they don’t always have that luxury.

Plus, the builders interviewed emphasize that not every home is worth saving. They usually choose homes built in the early half of the 20th century, which have the most sought-after architecture. Other builders whose practice is to tear down and start over are beginning to recognize this and emulating older Craftsman- and tudor-style homes.

“These 100-year-old homes have got a charm to them you don’t find in a lot of new homes today,” says Cale Kids, a remodeler in the M Streets and Vickery Place. “Even the new construction understands that what sells is the tradition and the style.”

And that’s the bottom line. Builders, even the ones striving for neighborhood continuity, are out to make a profit.

“I live in a house that everybody in the neighborhood and everybody I know says, ‘Now see, I wish builders would do this,’ but it cost us a ton to do it,” Bowen says. “Not everybody’s crazy like that.”