Our Story



   Oak Brook Estates began as a dense forest near the corner of Romence Road and Lovers Lane. Joel Mastenbrook and his father purchased the property with the intent of starting a retirement community, something that was far from common thirty years ago. They broke ground in 1986 began to clear and level the land. Joel had recently married his high school sweetheart, Karen (Birmann), and together they set forth on what has become their family’s livelihood.

   Joel and Karen brought in the first house in 1988, which became both their home and the park office for the next decade. They began to acquire model homes the following year, and would use the proceeds from each sale to purchase the next house. 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 swimming laps in the pool. Together, they attend as many of the kids’ band concerts, baseball games, and horseback riding lessons 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.