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Expand Your Home Without Starting Over

Room additions and residential expansions in San Jose, built from foundation to finish by one team.

You need more space, but moving means leaving a neighborhood you know and a home that works in most ways. A bedroom, bathroom, or family room addition gives you the square footage without the upheaval. In San Jose, where lot sizes vary and setback rules matter, adding on requires careful planning from the first sketch through the final walkthrough.

Cervantes Construction handles residential room additions with plumbing, structural work, and finish construction managed by the same team. Whether you're adding a primary suite, expanding a kitchen, or building out a second story, the work includes foundation prep, utility connections, framing, and interior finishes. Everything is designed to integrate with your existing home so the addition doesn't look or feel like an afterthought.

If you're ready to add space and want to understand what the process looks like for your San Jose property, reach out to start the conversation.

What Happens Between Foundation and Occupancy

Your addition starts with site prep and foundation work, followed by framing, roofing, and exterior closure. In San Jose, this often means coordinating inspections for footings, gas lines, and water service before any interior work begins. Plumbing and electrical rough-ins happen once the structure is weathertight, then insulation, drywall, and flooring follow in sequence.

When the work is done, you'll walk into a room that feels like it was always part of the house. Floors align, walls match, and utilities function without noise or delay. The addition doesn't settle differently or show gaps where old meets new because the structure was tied in correctly from the start.

Materials are chosen to match existing finishes where possible, and all utilities are brought to current code. The work does not include landscaping restoration or separate HVAC systems unless specified in the plan. Timelines depend on size and complexity but are outlined before work begins so you can plan around the construction.

What Homeowners Usually Want to Know

Before starting an addition, most people ask about permits, timelines, and how the new space connects to existing systems. These questions help clarify what the project involves and what to expect along the way.

How long does a room addition take?
A single-room addition typically takes two to four months depending on size, weather, and inspection schedules. Larger projects or second-story additions may take longer due to engineering and structural requirements.
What permits are required for a home addition?
Building, plumbing, and electrical permits are required for most additions in San Jose. The permitting process includes plan review and inspections at multiple stages, which are coordinated as part of the project timeline.
How is plumbing extended to the new space?
Water and drain lines are run from existing service points to the addition, with new branch lines installed during rough-in. All connections are pressure tested and inspected before walls are closed.
What happens to the exterior where old and new meet?
The addition is tied into the existing structure with proper flashing, matching siding, and continuous roofing. You won't see gaps, mismatched materials, or water intrusion points when the work is complete.
When can the new space be used?
The space is ready once final inspections pass, flooring is installed, and fixtures are connected. You can occupy it immediately, though paint and finishes may need a brief cure period depending on products used.

Cervantes Construction manages home additions across San Jose with a focus on how new construction integrates with existing systems and structures. If you're planning to add space and want a team that handles the full scope, contact us to discuss your project.