Thirty-One 11 Sunset

Flower Mound, Texas


  • Residential


  • mechanical / plumbing engineering
  • electrical engineering


  • 607,347 SF

BHB provided mechanical and electrical engineering services for the design of a new 16-story high-rise multifamily development on the shores of Lake Grapevine. The 210-unit apartment/townhome tower, Thirty-One 11 Sunset, broke ground in early 2023. It is part of a larger development called Lakeside Village that will also include a 12-story luxury hotel/condominium tower and a six-story office/retail tower that will begin construction in 2024 with long-term plans to add an additional six towers.

Lakeside Village will house six retail/restaurant spaces as an amenity for residents and visitors, along with two parking garages: a two-level, subterranean garage below the hotel/office building and another two-level, partially below grade garage next to Thirty-One 11 Sunset.

In order to stay within the allotted budget, Thirty-One 11 Sunset was redesigned to be 15 feet shorter than the original design. The new reduced height required strict coordination between MEP systems due to the decreased amount of ceiling space. It was a major undertaking to verify that all the systems designed up to that point will fit within the new measurements while still maintaining the project schedule.

The plumbing scope of the project included a central water heating and distribution system serving the apartment tower as well as independent systems to serve each of the three-level townhomes, storm drainage systems for multiple roof levels and the amenity deck, a Provent sanitary waste and vent system to serve the apartment units plus conventional sanitary systems for the amenity and townhome areas, and a natural gas distribution system for the entire building.

One challenging aspect of this project was the varied programming (apartment units, penthouse apartments, amenity spaces, garage levels, and townhomes) that resulted in differing floor plans. Our engineers had to do additional coordination to make sure all of the routing of piping coordinated with walls and ceilings of the floor below. As cost-saving measures, the design used a Provent single stack waste and vent system to reduce the amount of materials, labor, and space required for installation of the sanitary drainage system and a Teal boiler system that not only reduces the upfront cost to the owner but will be maintained by the provider, thus also reducing future maintenance costs.


The electrical distribution for this project was designed to minimize cost and equipment sizes by serving the facility at two different voltages. Meter packs for the residential levels of the apartment building were distributed in stacked electrical rooms to minimize conductor lengths and keep the meter packs out of sight from the building occupants and visitors.

Key People

  • Richard J. Watters, PE

  • Gibran Michel, DBIA, LEED AP

  • Paul Morris, PE