This Arlington Heights home is known by many simply as the “Cow House. “ And passersby find the penguin in the front yard as charming as the painted bovine standing guard on the roof.

Homeowner Donna Lässker laughs to think that those creatures, and other artful objects visible from the street, may have strangers wondering, “What must be inside the house?” Now, she is reveling in that discovery herself, recently having moved back in after eight months of living in a camper — along with husband Jan and daughter Andie — in the driveway. Thanks to a thoughtful interior remodel delivered by family friend and Fort Worth architect and interior designer Marta Rozanich of konstrukcio studio, the family’s artful and eclectic possessions are on view in a whole new way.

The Lässkers are collectors and creators. Donna is an artist whose mural of Jimi Hendrix riding a dophin can be seen at Doc’s Records; Jan is a musician. Both teach in the FWISD. They find comfort and energy in surrounding themselves with the art, family memorabilia and quirky collectibles that fill their home.

Donna bought the 1943 humble 1,200- square-foot, two bedroom-one bath house from its first owners in 1999, intending to flip it. But she knew it was her forever home, the same way she knew Jan was her guy when she spotted him at Ye Olde Bull and Bush, a pub on Montgomery Street (where they married in 2002).

“I fell in love with the house, then Jan did, and now Andie will inherit it. It is just us,” she says.

Because she felt an obligation to preserve a sense of the home as it was, as well as protect what her family had brought to it, the decision to remodel was not made lightly. The architect’s challenge was to give the family more breathing room by claiming attic space for a guest room/study upstairs and to open up the choppy dining and kitchen spaces to create a smooth backdrop for their collections. “I have known Donna and Jan forever,” Marta says. “Mixing work and friendship is daunting, but they knew I understood their wish to respect the history of the house and maintain its spirit.”

Donna cried when walls came down in the kitchen and dining room, but when the ceiling joists were torn out, her grief was visceral. Now, the comfortable dining area and the warm, clean-lined kitchen soothe her. The latter is a highly functional space where a gas stove has been replaced by an induction stovetop, but rustic touches keep the new compatible with the vintage. Plywood cut into broad planks creates a shiplaplike ceiling, but the original wood was repurposed wherever possible. A modern coffee station above a beverage refrigerator boasts a backsplash of ceramic tiles handmade by Donna, a child of the ’70s, to look like cassette tapes.

The walnut on the oversize island has already begun to acquire a handsome patina. The American Standard farmhouse sink is both practical and sleek, as are the matte black Cambria quartz countertops. Shaker-front custom cabinets stretch into open shelves that display vintage glassware and family antiques.

A soulful merging of old and new is the salvaged frame of a door that once stood in the kitchen. Marked over the years with the heights and names of family and friends, the growth chart was retrofitted to frame the entry to the laundry room.

Some decisions were harder to make than others. Removing built-in china cabinets was a tough call for Donna, but the payoff is custom cabinetry with plentiful display space, installed as a divider between the dining area and a hall bath. Hughes Cabinetry crafted the unit around a large tropical fish tank. Light channels through the renovated space from all sides.

Donna says of the magical results, “It feels like we added a whole other room without actually adding any square footage.” The attic addition gives Jan, who is Swiss, the extra space he had long envisioned. “In Switzerland, we use every square inch of our homes,” he says. “You would never find perfectly good space being used for stashing a suitcase.”

To avoid any roofline changes disruptive to the neighborhood’s vibe, Marta designed the add-on as virtually invisible to the street — with the exception of two dormers in the front of the house. “Those windows were all the front of the house was missing,” Jan says. “Now I can string my Christmas lights.”

The addition of stairs created a sweet spot for the family turntable, tucked beneath the white-oak steps and inset on a walnut counter. It’s the perfect spot for playing Donna’s collection of vinyl, begun when she was 7, now fills a custom pullout drawer.

That said, designing the stairs wasn’t easy. “No one realizes how much space they require,” Marta says. “It’s harder than you think to get it right.” But get it right, she did. And the scant 200-square-foot space with a 7-foot ceiling at the top of the stairs delivers a sunny guest suite with space enough for a Murphy bed, a comfortable chair, a desk and a large bathroom with a glass-walled shower that boasts a Kohler rainhead installed in a skylight. Bonus footage tucked beneath the steep pitch of the roof includes a play area complete with built-in game storage.

Donna says, “When we started I was scared. I loved the house for what it was. I wondered, ‘Will it feel like our home?’ It was a process of acceptance and trust. Marta gave us more room for our dreams.”