About Us

MASKS, LLC is wholly owned by Seth Simmons and was created to offer clients expanded services that go beyond traditional contracting capabilities. It is a licensed General Commercial Contractor doing business as (dba) SOUTHWEST DESIGN BUILDING (SWDB) in Arizona, Colorado, Oklahoma, Texas and Utah with plans to expand into New Mexico, and Nevada to give clients the resources needed to develop their operations throughout the southwest and west. Seth and his team has over 50-years’ experience managing and constructing projects throughout the United States in Healthcare, Retail, Commercial, Hospitality, Food and Beverage and Industrial totaling over $100 million. Understanding how important trust is in a contractor, Seth has built and maintained over the 

We’re here when you need us.
Project Types
  • Conceptual Phase
  • Design Phase
  • Bid Phase
  • Construction Phase
  • Post Construction Phase

SOUTHWEST DESIGN BUILDING has a staff of estimators, project managers, superintendents, project coordinators and accounting professionals; the best people are put in place to work for you!

We exceed expectations.

SOUTHWEST DESIGN BUILDING takes pride in being responsive to real needs by acknowledging that money and time are always tight, and performance must be measurable. We serve as an extension of the Owner - equivalent to staff that otherwise would have been hired, serving for the duration of the project.

Project types vary from raw land development, to multi-site mixed use, high-rise commercial, hospitality, healthcare, industrial and retail facilities programs. With each project being different from all others, SOUTHWEST DESIGN BUILDING'S commitment is to identify any areas where Owner risks exist, assign the best qualified resources, and manage the effort as a cost-effective, value-added advocate of the client's best interest.

​Commercial Contractor & Healthcare Construction (602) 595-6689

last 15 years, multiple long-lasting client relationships yielding repeat projects and satisfied clients. Clients rely on Seth and his team to serve on their behalf, ethically and responsibly and recognize SWDB’s commitment to quality, budget and schedule for all their construction needs. His commitment to this is proven by the fact that returning clients account for more than half of the business every year. 

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We pay attention to the details.