Home additions and room additions
Added bedrooms, bathrooms, family rooms and second stories, built to the permit set.
A home addition adds square footage to a house you already own: a bedroom, a primary suite, a family room, a sunroom or a second story. We build additions under CA License #1020290 and work from your designer's or engineer's plans.
Signs an addition makes sense: the house is the right location but too small, a family member is moving in, or a home office has taken over a bedroom. A second story keeps the yard; a ground-level wing keeps the stairs out. Which one fits depends on the lot's setbacks, the foundation and what the city or County allows.
A typical job runs in this order: site visit and written scope, plans and engineering, permit submittal, foundation and framing, roof and weather-tight stage, rough electrical and plumbing by licensed trade partners where a specialty class is required, inspections, insulation and drywall, finishes, final inspection. We tell you at the start which steps need a separate trade.
Published ranges, not quotes. HomeAdvisor lists San Diego additions at $42,779 to $136,828 with an average of $88,581; its national range is roughly $22,000 to $82,000 (HomeAdvisor, checked 2026-11-11). Your price depends on size, foundation, second story or not, and finishes.
Common questions
How long does an addition take?
After permits are issued, many additions take several months to build. Permit review adds time before that, and it varies by city or County office, so we ask for the current review time when we quote.
Do I need an architect?
Plans for an addition are drawn by a licensed designer, architect or engineer. We can work from your plans, and we talk through who draws them at the first visit.
Where we do this work
Home additions and room additions in Carlsbad
Additions, ADUs and rebuilds in Carlsbad, with city permits and a coastal-zone check.
Home additions and room additions in Escondido
Home additions, ADUs and fire or water rebuilds for Escondido's older housing stock.
Home additions and room additions in Encinitas
Additions, ADUs and whole-home work in Encinitas, with coastal and design-review checks.
Home additions and room additions in Del Mar
Careful additions and rebuilds in Del Mar, where design review and the coastal zone shape every project.
Home additions and room additions in Oceanside
Additions, ADUs and reconstruction in Oceanside, from coastal bungalows to inland tract homes.
Home additions and room additions in Carmel Valley
Room additions and renovations in Carmel Valley's newer, HOA-governed neighborhoods.
Home additions and room additions in Leucadia
Additions and rebuilds for Leucadia's small coastal lots along Highway 101.
Home additions and room additions in Rancho Santa Fe
Additions and rebuilds in Rancho Santa Fe, where County permits and the Association's Art Jury both apply.
Home additions and room additions in Cardiff
Additions and renovations for Cardiff-by-the-Sea's small lots near the lagoon and the coast.
Home additions and room additions in Olivenhain
Additions, ADUs and rebuilds on Olivenhain's larger semi-rural lots.
Home additions and room additions in Fallbrook
Additions, ADUs and fire or water rebuilds in Fallbrook's unincorporated rural neighborhoods.
Home additions and room additions in Fairbanks Ranch
Additions and rebuilds in Fairbanks Ranch, with association design review on top of County permits.
Home additions and room additions in Rancho Bernardo
Additions, renovations and fire or water rebuilds for Rancho Bernardo homes west of I-15.
Home additions and room additions in Solana Beach
Additions and rebuilds in Solana Beach, one of the oldest housing stocks in North County.
Home additions and room additions in Vista
Additions, ADUs and rebuilds for Vista's older neighborhoods, from the city core to the east side.
Home additions and room additions in La Costa
Additions and ADUs in La Costa, a master-planned part of Carlsbad with HOA and city review.
Home additions and room additions in 4S Ranch
Additions and ADUs in 4S Ranch's newer neighborhoods, under County rules and HOA approval.
Home additions and room additions in Rancho Penasquitos
Additions and renovations for Rancho Penasquitos' 1960s to 1980s family homes.
Home additions and room additions in San Marcos
Additions, ADUs and rebuilds in San Marcos, from older tracts to newer hillside neighborhoods.
Home additions and room additions in San Elijo Hills
Additions and ADUs in San Elijo Hills, a master-planned part of San Marcos with HOA review.
Home additions and room additions in Bonsall
Additions, guest houses and fire rebuilds on Bonsall's rural lots.
Home additions and room additions in North County San Diego
What to expect for building and rebuilding across North County: which office permits what.