Home Addition in Nob Hill
Custom Home builds home additions in Nob Hill at $550-$800 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 Nob Hill?
Home additions in Nob Hill typically cost $550-$800 per square foot in 2026. A 500 sqft addition ranges from $275K to $400K. Custom Home's design phase locks in your exact cost before construction starts.
Why Expand Your Nob Hill Home
Nob Hill’s strong property values and desirable neighborhoods make home additions a smart investment. Rather than uprooting to a new location, expanding your current home lets you stay in the community you chose. San Francisco’s historic housing stock, steep grades, and strict codes make experienced builders essential.
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 Nob Hill
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 Nob Hill.
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 Nob Hill Additions
Nob Hill 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.
Nob Hill Home Addition Permits
San Francisco’s Department of Building Inspection (DBI) processes all residential permits on Nob Hill. Projects involving historic properties require additional review by the Planning Department and, in some cases, the Historic Preservation Commission. Plan review timelines range from 8-16 weeks depending on project complexity and historic status. Seismic upgrade requirements are common for older structures and may affect project scope.
Custom Home manages the entire addition permitting process, including structural engineering review, plan submittal, and inspection coordination. Our experience with Nob Hill’s requirements helps keep the approval process on track.
Pricing for Home Addition in Nob Hill
Home addition costs in Nob Hill typically run $550-$800 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.
Nob Hill Permit Requirements
San Francisco's Department of Building Inspection (DBI) processes all residential permits on Nob Hill. Projects involving historic properties require additional review by the Planning Department and, in some cases, the Historic Preservation Commission. Plan review timelines range from 8-16 weeks depending on project complexity and historic status. Seismic upgrade requirements are common for older structures and may affect project scope. Custom Home manages the full addition permitting process, including structural engineering review.
Home Addition in Nob Hill: FAQ
How much does a home addition cost in Nob Hill?
Home additions in Nob Hill typically cost $550-$800 per square foot. A 400 sqft room addition generally ranges from $220K to $320K. 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 Nob Hill?
Home additions in Nob Hill 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.
Can my Nob Hill home support a second-story addition?
Most homes can be structurally reinforced for a second story. Custom Home's engineering team evaluates your foundation and framing during Phase 1 to determine what modifications are needed and includes those costs in the itemized scope.