Residential Additions
Design thoughtful additions and alterations for single-family homes and residential buildings up to four units, coordinating architecture, interiors, consultants, and contractors.
Transform your existing home with thoughtful additions and remodeling guided by Ortiz Mexia Projects, Inc. From early concepts and architectural design through permits, contractor coordination, and construction completion, the studio creates timeless, elegant residential environments. Serving homeowners in Los Angeles and Colorado’s Roaring Fork Valley, each project balances practical improvements, sustainability, technology, and lasting design character.

Integrated residential design services for additions, alterations, interiors, permitting, and construction guidance across selected service areas.
Design thoughtful additions and alterations for single-family homes and residential buildings up to four units, coordinating architecture, interiors, consultants, and contractors.
Receive full-service remodeling support spanning design, permit procurement, construction oversight, and project completion with a timeless, sustainability-minded approach.
Develop a cohesive home design from concept through Certificate of Occupancy, with hands-on guidance through design, permitting, bidding, and construction.
Navigate building permit requirements with assistance coordinating designs, consultants, contractors, and municipal agencies throughout the approval process.
Coordinate interior environments, cabinetry, furniture, and built-ins so expanded or remodeled spaces feel practical, elegant, and connected.
Keep project decisions aligned from early design through completion with detailed orchestration, consultant coordination, and construction administration.
A successful addition or remodel should feel like an intentional part of the home, not an afterthought. Ortiz Mexia Projects, Inc. coordinates architectural design, interiors, permitting, consultants, and contractors into one considered direction. For projects in Los Angeles or Colorado’s Roaring Fork Valley, the studio brings local project coordination, sustainable thinking, AI and VR tools, and an emphasis on timeless craftsmanship.

A design-led practice for homeowners seeking coordinated, enduring residential improvements.
Architecture, interiors, furniture, cabinetry, and built-ins can be coordinated through one design practice.
Elegant, durable design decisions help additions feel connected to established Los Angeles and Colorado homes.
The studio assists with municipal permitting and project coordination across its established service areas.
AI and VR tools support clearer design communication and immersive client understanding throughout the project.
Founder-led architectural and interior design guidance for residential projects.

Assoc. AIA, Principal
Santiago Ortiz is the founder and principal of Ortiz Mexia Projects, Inc., an architecture and design practice serving Los Angeles and Colorado's Roaring Fork Valley. Born and raised in Colombia, Santiago moved to Providence, Rhode Island, to pursue his passion for design, graduating from the Rhode Island School of Design in 1999 with degrees in Architecture and Fine Arts. After relocating to Los Angeles, he honed his craft at small architecture firms specializing in high-end custom residences and boutique commercial spaces before founding his own practice in 2006. Santiago is an Associate Member of The American Institute of Architects and brings a timeless, elegant sensibility to every project, from custom furniture and built-ins to full-scale residential construction. His work has been featured in Interior Design Magazine and the Los Angeles Times, reflecting his commitment to thoughtful, well-crafted design.
The most expensive portion varies by the project’s scope and existing conditions. Costs may be influenced by structural work, site preparation, mechanical and electrical systems, finishes, permitting, and the complexity of connecting new space to the existing home. A coordinated design and permitting process helps identify these factors early and align the addition with the homeowner’s priorities.
Share your goals with the studio and discuss a thoughtful path forward.
Residential addition and remodeling guidance for homeowners across Los Angeles and Colorado’s Roaring Fork Valley.
Los Angeles, CA
Primary Area
Roaring Fork Valley
Additional Area
By Appointment
Availability
Contact the studio to discuss location, scope, and project fit.
Professional membership held by principal Santiago Ortiz.
Ortiz-Wheeler Residence featured in the Venice Vista Home Tour.
Work featured in respected design and local publications.
Tell us about your property, goals, and location so the studio can discuss the right next step.
For immediate assistance, feel free to give us a direct call at +1 (310) 600-0241.
For immediate assistance, feel free to give us a direct call at +1 (310) 600-0241.