Extension Design
Develops custom additions and alterations for single-family homes and residential buildings, coordinating spatial planning, architectural character, sustainability, and client priorities.
Planning a house extension involves more than drawing plans. Ortiz Mexia Projects, Inc. helps homeowners understand architectural design, permitting, construction guidance, and the decisions that shape overall project costs. With a timeless, sustainable approach and support from concept through completion, the studio creates thoughtful additions and alterations tailored to each home, site, lifestyle, and budget.
Integrated architectural services for residential additions, alterations, permitting, interiors, and construction guidance.
Develops custom additions and alterations for single-family homes and residential buildings, coordinating spatial planning, architectural character, sustainability, and client priorities.
Guides homeowners, consultants, and contractors through building permit procurement, helping move an extension from design development toward approved construction documentation.
Provides project guidance across design, permitting, contractor bidding, construction, and completion, maintaining coordination among clients, consultants, and general contractors.
Coordinates interior design, custom cabinetry, furniture, and built-ins so the new extension feels coherent with the home’s architecture and everyday use.
Approaches historically sensitive remodels and additions with care, preserving architectural integrity while integrating modern sustainable systems and technologies where appropriate.
Uses immersive VR presentations and three-dimensional models to help clients experience proposed spaces and make more informed design decisions.
A well-considered extension can improve how your home works while protecting its architectural character. Ortiz Mexia Projects, Inc. brings design, permitting, interiors, technology, and construction guidance together in one coordinated practice. The studio develops sustainable, timeless solutions for additions and alterations, helping clients understand key choices and experience proposed spaces through detailed drawings, three-dimensional models, and VR immersion.
A design-led practice connecting architectural vision with practical project guidance.
Architecture, interiors, cabinetry, furniture, and built-ins can be coordinated through one design practice.
Designs prioritize elegant, enduring spaces rather than short-lived trends or disconnected additions.
Support extends from initial design and permitting through contractor coordination, construction, and Certificate of Occupancy.
VR and three-dimensional models help clients understand proposed spaces before construction begins.
Founder Santiago Ortiz leads a thoughtful, multidisciplinary residential design practice.
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.
Architect fees for extension plans vary according to the project’s scope, complexity, existing conditions, level of design service, permitting needs, and construction guidance required. Ortiz Mexia Projects, Inc. does not publish fixed pricing because each addition or alteration is custom. An initial discussion can clarify the intended work, expected services, and the factors that will shape a project-specific proposal.
Talk with the design team about your home, goals, and project requirements.
By appointment, the studio serves selected communities across Los Angeles and Colorado’s Roaring Fork Valley.
Los Angeles and Roaring Fork Valley
Service Area
By Appointment Only
Availability
Residential Design
Project Focus
Share your extension goals and learn whether the studio is a fit.
Professional affiliation held by principal Santiago Ortiz.
Residence featured in the Venice Vista Spring Home Tour.
Projects featured in Interior Design Magazine and Los Angeles Times.
Use the contact form to share your project goals, property context, and preferred next steps.
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.