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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 6 of 973

4 Corners Flooring

B| C15GRANADA HILLS, CA 91394
CSLB 835794
(818) 612 2575View profile

4 Eco Living

BPLAYA DEL REY, CA 90293
CSLB 827016
(310) 299 6674View profile

4 Kings Construction Site Services

BLOS ANGELES, CA 90061
CSLB 1157205
(323) 559 4945View profile

4 N B Construction

BPOMONA, CA 91768
CSLB 1012663
(909) 643 6654View profile

4 Nu Construction

BBEVERLY HILLS, CA 90212
CSLB 875392
(310) 344 8989View profile

4 R'S Construction Inc

BHAWTHORNE, CA 90250
CSLB 1096647
(310) 357 1556View profile

4 Seasons Builder

BLONG BEACH, CA 90802
CSLB 1048300
(323) 802 5054View profile

4 Seasons Construction & Design

BWEST HILLS, CA 91304
CSLB 790488
(818) 468 8244View profile

4 Triplett Construction Corporation

B| D63LOS ANGELES, CA 90045
CSLB 1150200
(630) 930 2473View profile

4 Waves Management LLC

BLAKEVIEW TERRACE, CA 91342
CSLB 1100575
(213) 598 9720View profile

4-BY Construction & Plastering Inc

B| C35GARDENA, CA 90248
CSLB 1141977
(310) 345 9396View profile

413 Builders

BLOS ANGELES, CA 90064
CSLB 904389
(310) 207 1300View profile

4214 Fulton Builders Inc

BENCINO, CA 91316
CSLB 882603
(818) 645 5696View profile

43Five60 Construction Group Inc

BCOVINA, CA 91723
CSLB 1131043
(323) 708 0772View profile

4Clover Construction

BALHAMBRA, CA 91803
CSLB 1148930
(626) 997 0077View profile

4D Construction

B| C-5AZUSA, CA 91702
CSLB 1039975
(310) 908 5625View profile

4G Builders Inc

BLYNWOOD, CA 90262
CSLB 977323
(310) 995 8012View profile

4K Patios

BWEST HILLS, CA 91304
CSLB 1134465
(818) 287 1536View profile

4Ourbath

BMONTEBELLO, CA 90640
CSLB 793150
(323) 528 3598View profile

4Site Construction

BLOS ANGELES, CA 90026
CSLB 971233
(323) 905 6745View profile

5 - Star Construction

BLANCASTER, CA 93534
CSLB 702053
(213) 591 1174View profile

5 Points Sash & Doors

B| C17TORRANCE, CA 90502
CSLB 697862
(310) 326 4141View profile

5 Star Construction

BGARDENA, CA 90247
CSLB 1062501
(213) 273 4454View profile

5 Star Builders Inc

A| B| C10| C36| C46WEST HILLS, CA 91304
CSLB 1012362
(818) 687 3113View 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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  • Find a licensed garage conversions contractor in Irwindale
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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.

Get matched with a licensed pro

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