HRH Engineering is a mechanical and design engineering consultancy at 122 15th St, Del Mar, CA 92014, led by Hamid Reza Hosseini, P.E., and located in the same building as creative services firm JS Enterprises. Hosseini founded HRH Engineering in 2021 after arriving in the United States in 2013 and completing a thorough review of California's regulatory landscape. He gained five years of municipal engineering experience with the City of Oceanside before obtaining his California Professional Engineer (P.E.) mechanical license and launching his own practice. His education includes coursework through UC San Diego Extension, and he previously held a license from the Esfahan Society of Consulting Engineers in Iran, where he also served as a licensed justice expert in biomechanic engineering and worked with biomedical equipment. The firm specializes in designing and managing HVAC, plumbing, process piping, fire protection, solar, and energy management systems across residential and commercial building types, using AutoCAD, REVIT, Energy Pro, Inventor, and SolidWorks. Residential services include ADU (Accessory Dwelling Unit) plans, custom home design, kitchen remodels, home additions, granny flats, green home design, and coastal exemption documentation. Hosseini's design and drafting division offers complimentary initial consultations, uses advanced laser measurement instruments, and delivers construction documents at competitive fixed fees. Homeowners pursuing major renovation projects in Del Mar often coordinate engineering plans with local architecture firms such as Batter Kay Associates Architects. HRH Engineering operates Monday through Saturday, 9 AM to 5 PM, with wheelchair-accessible entrance and parking.