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Licensed under Class B (General Building)

Second-Story Additions in Irwindale, CA — CSLB-Licensed Contractors

Find CSLB-licensed second-story addition contractors in Irwindale, CA. Every listing shows an active licence number you can check yourself.

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What to Expect from Second-Story Additions in Irwindale

A second-storey addition in Irwindale is the most structural thing most homeowners ever commission. Everything below has to carry what goes above, so the project starts with an engineer looking at the foundation and the existing walls, not with a floor plan.

Expect the house to be open to the weather for a period. The roof comes off, which means temporary protection, and it means the schedule is genuinely weather-dependent in a way a kitchen remodel is not. Ask how the house is protected between tear-off and dry-in, and what happens if it rains.

The staircase is the detail people underestimate. It has to land somewhere sensible on both floors and it consumes real square footage on the level you already live on. A design that adds 800 square feet upstairs while eating 60 downstairs is a different proposition from the one on the drawing.

  • Structural assessment of foundation and existing walls
  • Engineering and plan check submission
  • Roof removal and weather protection
  • Framing the new floor and walls
  • Staircase construction and downstairs reconfiguration
  • Extending plumbing, electrical and HVAC upward

Why CSLB Licensing Matters

Adding a storey involves structural, framing, roofing, plumbing, electrical and finish work, which puts it well inside Class B (General Building). It is the classification CSLB defines for structures requiring at least two unrelated trades, and this work requires many more than two.

Each contractor here holds that licence, active, at a Irwindale address, with the number linked to the register. On a project of this size it is worth checking the record again before each large payment, not only at signing.

The register says nothing about whether a firm has done this before, and second-storey work is not a scaled-up remodel. Ask how many they have completed in the last three years, whether any needed the foundation reinforced after the engineer looked, and what that did to the budget. A contractor who has a number for that has done the work; one who says it never comes up has not done much of it.

Every licence number below links to its record at cslb.ca.gov, where you can confirm status and expiry yourself.

Licensed Second-Story Additions Contractors in Irwindale

17 registered in Irwindale · 23,334 active CLEAR licences across Los Angeles County · page 55 of 973

Allgood Construction Inc

BBURBANK, CA 91502
CSLB 1122768
(626) 880 8800View profile

Alli Mirza

BPASADENA, CA 91107
CSLB 536982
(323) 833 6158View profile

Alliance City Builders

BNORTH HILLS, CA 91343
CSLB 1142080
(818) 294 1877View profile

Alliance Commercial Construction Inc

B| C-8| C29CARSON, CA 90746
CSLB 1152518
(714) 805 3298View profile

Alliance Construction Services

BTARZANA, CA 91335
CSLB 902902
(818) 298 3368View profile

Alliance Design Build

BLAKEWOOD, CA 90712
CSLB 1119055
(760) 680 5463View profile

Alliance Industrial Refrigeration Services Inc

B| C20| C38WALNUT, CA 91789
CSLB 825297
(909) 869 8660View profile

Alliance Property Group Inc

BEL SEGUNDO, CA 90245
CSLB 916673
(424) 369 4568View profile

Alliant Construction Services Inc

BDIAMOND BAR, CA 91765
CSLB 1061441
(818) 612 8200View profile

Allied Building and Technologies Inc

B| C10| C46NORTHRIDGE, CA 91324
CSLB 913530
(818) 671 3981View profile

Allied Coastal Construction Inc

BHUNTINGTON PARK, CA 90255
CSLB 1014187
(323) 590 3277View profile

Allied Construction and Services

BSANTA CLARITA, CA 91350
CSLB 770808
(661) 390 2559View profile

Allied Contractors Inc

BSANTA MONICA, CA 90405
CSLB 97854
(310) 396 4514View profile

Allied Design-Build Inc

B| C39LOS ANGELES, CA 90006
CSLB 1049636
(847) 489 7999View profile

Allied Enterprise Group Inc

BBURBANK, CA 91506
CSLB 1019476
(818) 472 7248View profile

Allied Maintenance & Construction Inc

BVALLEY VILLAGE, CA 91607
CSLB 1149070
(818) 430 9841View profile

Allied Restoration Services LLC

BWEST COVINA, CA 91791
CSLB 1143476
(888) 860 1003View profile

Alligator Construction

BNORTH HOLLYWOOD, CA 91606
CSLB 996055
(818) 577 6302View profile

Allington Company

BPALMDALE, CA 93551
CSLB 420195
(310) 291 8148View profile

Allinonebuildersolutions

BMONTEREY PARK, CA 91754
CSLB 1139160
(323) 743 7736View profile

Allo Construction Co

BPASADENA, CA 91107
CSLB 719847
(818) 253 6838View profile

Alloi Inc

BLOS ANGELES, CA 90045
CSLB 924675
(310) 204 2811View profile

Alliance Environmental Group LLC

ASB| B| C-2| C20| C21| C22| D64| HAZAZUSA, CA 91702
CSLB 716538
(626) 633 3500View profile

Allianz General Engineering Contractor Inc

A| B| C10| C36SAN GABRIEL, CA 91776
CSLB 1047393
(626) 780 6694View profile
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How to Get Started

  1. 1

    Check the licence

    Open the CSLB record from any listing below and confirm the licence is active and the classification matches the work. It takes seconds and it is the one thing you can verify without asking anyone.

  2. 2

    Call three recent references

    Ask each contractor for three jobs finished in the last year, then actually call them. Ask what went wrong and how it was handled — every project has something, and the answer tells you more than a list of successes.

  3. 3

    Tell us about the job

    Send us the scope and we will connect you. No account, no fee, and we do not sell your details on.

Licence first. References second. Reviews last. Why that order.

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Related Services in Irwindale

These sit under the same Class B (General Building) licence, so the same contractors are qualified for them.

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Frequently Asked Questions

Can my house support a second storey?+

That depends on the foundation and the existing wall framing, and only an engineer can answer it for your house. Some homes need footings reinforced or shear walls added first. Get that assessment before you fall in love with a floor plan, because it can change the budget substantially.

How many contractors handle second-storey additions in Irwindale?+

The register shows 17 holding an active Class B licence at a Irwindale address, and 23,334 across Los Angeles County. Class B is the classification this work falls under, so it lists the same pool as other general building pages.

Do we have to move out during the work?+

Often yes, at least for the phase when the roof is off. Ask for that period to be identified in the schedule up front, because temporary accommodation is a real cost that rarely appears in the initial quote.

How long does a second-storey addition take?+

It varies with engineering, plan check and inspection scheduling in your jurisdiction more than with the building itself. Ask for a schedule that names the inspection milestones rather than a single completion date.

Does a second-storey addition need permits from Building & Safety?+

Yes — structural plans, roof removal and new floor area require plan check and staged inspections through Building & Safety.

Every contractor here holds an active CSLB licence

Check any licence yourself in one click. When you are ready, tell us about the job and we will connect you.

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