Our Story

   Oak Brook Estates began as a dense forest near the corner of Romence Road and Lovers Lane. Don Mastenbrook had owned the property for years and had thoughts of starting a retirement community, something that was far from common thirty years ago. Oak Brook broke ground—literally—in 1986 when the land was cleared and leveled. 

The first house was brought into the park in 1988. Don’s son Joel had recently married his high school sweetheart, Karen (Birmann), and the young couple moved into the that first home to set forth on what has become their family’s livelihood.

   For the next decade, Joel and Karen’s home doubled as the park’s business office. Oak Brook began to acquire model homes and would use the proceeds from each sale to purchase the next house. At that time, Joel was a manager at the local Jewel-Osco grocery store, and would come home to work on Oak Brook in the evenings. As the park developed, Joel poured every pad, sidewalk, and patio, while Karen spent endless hours planting and watering a new lawn for each home. Their first daughter, Jessica, was born in 1990 and grew up with “many, many grandparents” in the park.

   The final pad was poured and the last lawn was planted in the summer of 1996. Over the course of eight years, Oak Brook had grown from the Mastenbrooks’ house and a wooded backyard to over 130 homes.

   Today, Joel and Karen still run the family business from their home near Texas Corners. They welcomed a son, Jacob, to the family in 1998, along with their second daughter, Laura, in 2004. As the children have gotten older, they have begun to take on varying responsibilities under Joel and Karen’s guidance.

   In his time away from Oak Brook, Joel enjoys fishing, reading his daily newspaper, and fixing anything that appears to be broken. Karen can typically be found baking something in the kitchen or tending to her flock of chickens. Together, they attend as many of the kids’ and grandkids’ events as possible.

The Mastenbrooks are proud of many things about Oak Brook Estates, but a few are worth specific mention: 

o   Margot Schouwburg was the park's the first resident and lived in Oak Brook for twenty-seven years. She was a European immigrant who came to America after losing most of her family in a WWII bombing. Margot passed away in 2016 at the age of 95. 

o   The average residency in Oak Brook is over twelve years, which adds to the sense of community within the park.

o   In nearly thirty years of operation, Joel and Karen have never had to evict a resident.