Room Addition Pasadena CA — Costs, Process & 2026 Guide

Room Addition in Pasadena, CA — Costs, Process & 2026 Guide

Room additions are one of the most popular construction projects in Pasadena. With high land costs that make buying a larger home expensive, and a strong housing market where the cost of moving far exceeds the cost of adding space, many Pasadena homeowners choose to build out rather than buy up. APLA Construction (CA Lic #1136359) handles room additions throughout Pasadena — from single bedroom additions to full primary suite build-outs and second story additions.

Room Addition Costs in Pasadena (2026)

• Bedroom addition (200–400 sq ft): $90,000–$170,000
• Primary suite addition (400–600 sq ft, including bath): $130,000–$240,000
• Family room addition (400–600 sq ft): $110,000–$200,000
• Second story addition (full upper floor): $220,000–$420,000
• Garage conversion to living space (without ADU designation): $70,000–$130,000

Room addition permits in Pasadena are submitted to the City of Pasadena Planning and Development Department — separate from LADBS. Pasadena permit fees for additions are $5,000–$15,000 depending on project scope. See our second story addition guide for Los Angeles.

What’s Included in a Pasadena Room Addition

• Architectural plans and structural engineering
• City of Pasadena permit submission and plan check management
• Foundation work (slab or raised foundation extension)
• Framing, roofing, and exterior finishes matched to the existing home
• Electrical, plumbing (if applicable), and HVAC extension
• Insulation, drywall, interior finishes matched to the home’s existing character
• All inspections through final sign-off

Room Addition vs ADU in Pasadena

Many Pasadena homeowners consider both a room addition and an ADU at the same time. The key difference: a room addition is internal to the main house, while an ADU is a separate unit that generates rental income. If the goal is more space for personal use (primary suite, home office, family room), a room addition is the right choice. If the goal is rental income, an ADU delivers far better ROI. If both goals exist, APLA can design a project that accomplishes both simultaneously. See our full comparison guide: ADU vs Room Addition Los Angeles.

Frequently Asked Questions — Room Addition Pasadena CA

How much does a room addition cost in Pasadena?

A bedroom addition in Pasadena costs $90,000–$170,000 in 2026. A primary suite addition (bedroom plus bathroom) runs $130,000–$240,000. A full second story addition costs $220,000–$420,000 depending on size and complexity. These figures include architectural plans, City of Pasadena permits, and all construction.

Does Pasadena require permits for room additions?

Yes. All room additions in Pasadena require permits from the City of Pasadena Planning and Development Department. Structural work requires stamped engineering calculations. Properties in historic districts may require additional design review. APLA manages all permit submissions for Pasadena room addition projects.

Does APLA do room additions in Pasadena?

Yes. APLA Construction handles bedroom additions, primary suite additions, second story additions, and family room additions throughout Pasadena. Call (818) 818-4419 for a free on-site estimate.

Start Your Pasadena Room Addition

Call: (818) 818-4419
Email: info@aplaconstruction.com
CA General Contractor License #1136359

Serving Pasadena, Arcadia, San Marino, Monrovia, Altadena, Sierra Madre, and the San Gabriel Valley. See our complete Room Addition Los Angeles guide.