Typical Timeline for a Garage Conversion in Los Gatos

How Long Does a Garage Conversion Actually Take?

If you are considering converting your Los Gatos garage into a living space, the first question on your mind is probably: how long will this take? The answer depends on the scope of work, the condition of your existing garage, and how smoothly the permitting process goes. But a realistic range for most projects is 4 to 7 months from design kickoff to final inspection.

That timeline is significantly shorter than building a new detached ADU or a home addition, which is one of the main reasons garage conversions have become so popular in Los Gatos and across the Bay Area. You are working with an existing structure, so the foundation, framing, and roof are already in place.

This guide breaks down every phase of the timeline, gives you a clear picture of what happens during each stage, and explains the factors that can speed things up or slow things down.

The Full Timeline at a Glance

Here is a phase-by-phase overview of a typical garage conversion project in Los Gatos:

Phase	Duration	Key Activities
Design and planning	2-4 weeks	Site assessment, architectural plans, engineering, Title 24 energy report
Permitting	4-10 weeks	Plan submittal, building department review, corrections (if needed), permit issuance
Pre-construction	1-2 weeks	Material ordering, subcontractor scheduling, site preparation
Construction	8-16 weeks	Demolition, structural work, rough MEP, insulation, drywall, finishes
Inspections and close-out	1-2 weeks	Final inspections, punch list, certificate of occupancy
Total	4-7 months	Start to finish

Each of these phases has its own rhythm and its own potential for delays. Let’s walk through them in detail.

Phase 1: Design and Planning (2 to 4 Weeks)

The design phase is where the entire project takes shape. Rushing through it creates problems that surface during permitting or construction, costing you more time than you saved.

Site Assessment

A qualified design-build team starts with a thorough evaluation of your existing garage. This includes measuring interior dimensions, checking ceiling height, evaluating the slab condition, inspecting the structural framing, and documenting the location of your electrical panel, water lines, and sewer connections.

For garage conversions specifically, the assessment also looks at the garage door opening (which will become a new wall, window, or door assembly) and any exterior work needed to match the new facade to your home.

Architectural Plans and Engineering

With the site data in hand, your architect creates detailed construction drawings. These include floor plans, elevations, electrical layouts, plumbing diagrams, and structural details. If your conversion involves removing or modifying load-bearing walls, a structural engineer prepares calculations and details.

A Title 24 energy compliance report is also prepared during this phase. California requires this for any project that converts an unconditioned space into a habitable room.

Custom Home’s Two-Phase Approach

Custom Home’s design-build model front-loads the design work in Phase 1. By the end of this phase, you have complete construction documents, 3D renderings of the finished space, and a locked-in construction price. This approach eliminates the uncertainty that comes from getting a vague estimate before plans are finalized. You know exactly what you are getting and exactly what it costs before a single wall is opened up.

Phase 2: Permitting (4 to 10 Weeks)

Permitting is the phase where timelines vary the most. The Town of Los Gatos follows California’s ADU legislation, which requires a complete application to be reviewed within 60 days. In practice, the total permitting cycle depends on the quality of your initial submittal.

What Happens During Plan Review

After you submit your plans to the Los Gatos Building Division, a plan checker reviews the documents for compliance with California Building Code, Title 24 energy standards, plumbing and electrical codes, and the town’s objective design standards.

If the plans are complete and code-compliant, you may receive approval and your permit within 4 to 6 weeks. If the building department identifies issues, they will issue a correction letter detailing what needs to be revised.

Correction Cycles

Correction requests are the number one cause of permitting delays. Each round of corrections can add 2 to 4 weeks to your timeline as the designer makes revisions and resubmits, then the building department re-reviews. Some projects go through two or even three correction cycles.

The best defense against this is submitting thorough, detailed plans the first time. This is where an experienced design-build firm earns its fee. A team that has permitted multiple projects in Los Gatos knows the building department’s expectations and common correction triggers.

Permit Fees and Timing

Permit fees in Los Gatos for a garage conversion typically range from $5,000 to $20,000 depending on the project’s valuation and scope. Fees are paid at the time of permit issuance, not at submittal. Plan ahead so that fee payment does not create an unnecessary gap before construction can begin.

Phase 3: Pre-Construction (1 to 2 Weeks)

Once your permit is issued, the project moves into pre-construction. This short phase covers material ordering, subcontractor scheduling, and site preparation. Your contractor orders long-lead items like windows, cabinetry, and plumbing fixtures. Experienced teams begin sourcing during the permitting phase so materials arrive before construction needs them. The garage is cleared, temporary protection is installed for adjacent areas of your home, and utility disconnects are scheduled if the electrical panel needs to be relocated or upgraded.

Phase 4: Construction (8 to 16 Weeks)

Construction is the longest and most variable phase. A straightforward conversion of a well-maintained two-car garage with standard plumbing can be completed in 8 to 10 weeks. A project that involves structural modifications, slab plumbing, panel upgrades, and high-end finishes may take 14 to 16 weeks.

Weeks 1 to 2: Demolition and Structural Work

The garage door is removed and the opening is framed in. Interior walls are stripped to the studs if needed. Any structural modifications (header changes, wall removals, foundation repairs) happen during this phase. If the project includes slab plumbing for a bathroom or kitchen, the concrete is cut, trenched, and new drain and supply lines are installed before the slab is patched.

Weeks 2 to 4: Rough Mechanical, Electrical, and Plumbing (MEP)

Electricians run new wiring, install boxes and panels, and set up circuits for appliances, lighting, and HVAC. Plumbers install supply and drain lines for sinks, showers, and toilets. HVAC technicians install ductwork or a mini-split system. All of this “rough” work happens behind the walls before they are closed up.

Rough Inspections

After rough MEP is complete, the building department conducts inspections. These typically include:

• Framing inspection: Verifies structural work, fire blocking, and wall framing
• Rough electrical inspection: Checks wiring, box placement, panel work, and grounding
• Rough plumbing inspection: Confirms drain slopes, venting, and supply line installation
• Rough mechanical inspection: Reviews HVAC ductwork and equipment placement

Each inspection must pass before the next phase of work can begin. If an inspector finds an issue, the correction adds a day or two. Most experienced contractors schedule all rough inspections on the same day or within the same week to keep the project moving.

Weeks 4 to 6: Insulation, Drywall, and Rough Finishes

Once rough inspections pass, insulation is installed in walls and ceilings to meet Title 24 requirements. An insulation inspection follows. Then drywall is hung, taped, and finished. This phase also includes any exterior stucco work, siding, or trim where the garage door opening was filled in.

Weeks 6 to 10 (or Longer): Finish Work

The final stretch of construction includes flooring installation, cabinet and countertop installation, plumbing fixture hookups, electrical device installation (outlets, switches, light fixtures), painting, trim carpentry, and final HVAC commissioning. This is the most detail-intensive phase, and the timeline depends heavily on the complexity of finishes and the availability of specialty materials.

Phase 5: Final Inspections and Close-Out (1 to 2 Weeks)

Final Building Inspection

The building department conducts a final inspection to verify that all work matches the approved plans and meets code. This covers structural, electrical, plumbing, mechanical, fire safety, and energy compliance. If everything passes, the inspector signs off and the building department issues a certificate of occupancy (or equivalent approval for ADU conversions).

Punch List

After the final inspection, you walk through the space with your contractor to identify any remaining items that need attention: paint touch-ups, hardware adjustments, minor finish corrections. A good contractor addresses punch list items within a few days.

Factors That Speed Up Your Timeline

Not every project takes 7 months. Here is what helps projects finish faster:

• Complete, code-compliant plans submitted the first time. Avoiding correction cycles can save 4 to 8 weeks in permitting.
• A structurally sound garage. If the existing framing, slab, and foundation are in good condition, you skip the most time-consuming structural repairs.
• No slab plumbing. If you are converting to a home office or flex space without a bathroom, you eliminate one of the most labor-intensive construction tasks.
• Pre-ordering long-lead materials. Ordering windows, cabinets, and fixtures during the permitting phase means they arrive before construction needs them.
• An experienced local contractor. A team familiar with Los Gatos building department procedures, inspector expectations, and local subcontractor availability moves faster than one learning on your project.

Factors That Slow Down Your Timeline

These are the most common sources of delay in Los Gatos garage conversion projects:

• Permit correction cycles. Each round of revisions and re-review adds 2 to 4 weeks.
• Electrical panel upgrades. If your home’s main panel cannot support the added load, upgrading it may require coordination with PG&E, which can add 2 to 6 weeks.
• Structural surprises. Hidden moisture damage, termite damage, or an undersized foundation discovered after demolition begins can add weeks while engineering solutions are developed and additional permits are obtained.
• Slab plumbing complications. Trenching through existing slabs to connect drain lines is one of the most time-sensitive tasks. If the existing sewer line is in poor condition or the routing is complex, this phase takes longer.
• Material lead times. Custom windows, specialty fixtures, and imported tile can have lead times of 6 to 10 weeks. Planning for these early avoids mid-project stalls.
• Weather. While Bay Area weather is generally favorable for construction, heavy rain during the winter months can delay exterior work, slab work, and inspections.

How This Compares to Other Project Types

Understanding the garage conversion timeline in context helps you evaluate whether this is the right project for your goals:

Project Type	Typical Timeline	Key Difference
Garage conversion	4-7 months	Uses existing structure
Detached ADU (new build)	8-14 months	Requires foundation, framing, full exterior
Home addition	8-12 months	Ties into existing structure, more complex permitting
Whole-home remodel	10-18 months	Largest scope, most coordination

A garage conversion is the fastest path to new livable square footage, which is a major advantage for Los Gatos homeowners who want results without a year-long construction project.

Start With a Clear Plan

The fastest garage conversions are the ones that invest the most time up front in design, planning, and thorough documentation. Custom Home’s two-phase process is built around this principle: Phase 1 delivers complete plans, engineering, energy compliance, and a locked-in construction price. Phase 2 is a streamlined build with no guesswork.

If you are ready to explore what a garage conversion could look like for your Los Gatos home, the first step is a site assessment.

Contact Custom Home to schedule a free consultation and get a realistic timeline for your garage conversion project.