Home Addition in Union City
Custom Home builds home additions in Union City at $325-$500 per square foot. Whether you need a second-story addition, ground-floor expansion, or bump-out, our two-phase process delivers 3D visualization and itemized pricing before construction starts.
How much does a home addition cost in Union City?
Home additions in Union City typically cost $325-$500 per square foot in 2026. A 500 sqft addition ranges from $163K to $250K. Custom Home's design phase locks in your exact cost before construction starts.
Why Expand Your Union City Home
In Union City’s competitive housing market, expanding your current home often makes more financial sense than buying larger. A well-planned addition adds both space and property value. The East Bay’s combination of value and lifestyle continues to attract quality-minded homeowners.
Custom Home designs and builds home additions with the same two-phase process we use for custom homes. You see the complete addition in 3D and receive itemized pricing before construction begins.
Types of Home Additions We Build in Union City
Second-Story Additions
Double your living space by building up rather than out. Second-story additions are ideal when lot coverage limits prevent ground-floor expansion. Custom Home’s structural engineers evaluate your existing foundation to determine what reinforcement is needed.
Ground-Floor Room Additions
Extend your home’s footprint with new bedrooms, family rooms, or home offices. Ground-floor additions integrate with your existing layout and maintain single-level living, which is especially valued in Union City.
Bump-Outs and Extensions
Smaller expansions that make a significant difference: extend your kitchen, enlarge a bathroom, or add a sunroom. Bump-outs typically cost less and complete faster than full additions.
Structural Considerations for Union City Additions
Union City is located in a seismically active region, which means home additions must meet current seismic codes. Custom Home’s engineering team handles foundation evaluation, load-bearing wall modifications, and seismic design for every addition project. Whether you are adding a second story or expanding your footprint, structural engineering is included in our Phase 1 design process.
Union City Home Addition Permits
Union City’s Building Division processes residential construction permits with typical plan review times of 3-6 weeks. The city accepts applications in person and offers pre-application consultations to help homeowners understand requirements before submitting plans.
Custom Home manages the entire addition permitting process, including structural engineering review, plan submittal, and inspection coordination. Our experience with Union City’s requirements helps keep the approval process on track.
Pricing for Home Addition in Union City
Home addition costs in Union City typically run $325-$500 per square foot, similar to new construction pricing. Second-story additions may cost more due to structural reinforcement requirements. Custom Home's Phase 1 design process locks in exact pricing before construction begins.
Union City Permit Requirements
Union City's Building Division processes residential construction permits with typical plan review times of 3-6 weeks. The city accepts applications in person and offers pre-application consultations to help homeowners understand requirements before submitting plans. Custom Home manages the full addition permitting process, including structural engineering review.
Home Addition in Union City: FAQ
How much does a home addition cost in Union City?
Home additions in Union City typically cost $325-$500 per square foot. A 400 sqft room addition generally ranges from $130K to $200K. Second-story additions may cost more due to structural reinforcement. Custom Home locks in exact pricing during Phase 1.
How long does a home addition take in Union City?
Home additions in Union City typically take 6-12 months from design to completion. Second-story additions require 8-14 months due to additional structural work. Custom Home's design phase ensures construction runs efficiently and on schedule.
Do I need to move out during a home addition in Union City?
For most additions, you can remain in your home during construction. Second-story additions may require temporary relocation during certain phases. Custom Home plans the construction sequence during the design phase so you know what to expect.