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Find Basement remodelers in Altadena

Avatar for McCormick Home Builders, Inc.
McCormick Home Builders, Inc.
4.7(
42
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2017

Free estimates

Customers say: True professional

"Our kitchen remodel exceeded our expectations, providing us with a beautiful and highly efficient space for cooking and gathering. We're thrilled with the results, as the new design seamlessly integrates style and functionality."
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+1

Response time6 hrs
Recommended by17%of homeowners
Home Pro Remodeling & Construction, Inc.
4.1(
31
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2019

Free estimates

Credit card accepted

"After calling a few companies, we found Home pro remodeling. Ariel the manager gave us a good offer for the retaining wall, it was the best offer we received compare to other companies ! His guys are super professional, nice and clean. We were very happy with the experience. If you are looking to remodel your home , Home pro remodeling is definitely the best in the area! They are the real deal."
Response time5 days
Recommended by77%of homeowners
Avatar for CONTINENTAL REMODELING INC
CONTINENTAL REMODELING INC
5.0(
6
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2023

Free estimates

Credit card accepted

"I work with Continental Remodeling as their insulation subcontractor. Their team is amazing to work with, very responsive, organized and professional. Would highly recommend if I was looking to remodel or build new construction. Their work is high quality and unique."
Full Home Remodel (Woodland Hills)
Full Home Remodel (Woodland Hills)
Full Home Remodel (Woodland Hills)
Full Home Remodel (Woodland Hills)
Full Home Remodel (Woodland Hills)

+9

Response time2 days
Recommended by66%of homeowners
Avatar for Beneflipper Construction Corp
Beneflipper Construction Corp
4.8(
20
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2020

Free estimates

Small jobs welcome

"Very knowledgeable, I was able to book an appointment the next day the contractor came out and walked me through my kitchen renovation options."
Before
1
After
Exterior Side Entrance
Exterior Front Entrance

+122

Response time2 days
7 neighbors recently requested a quote
Recommended by43%of homeowners
Avatar for Monroy's Father & Son Construction
Monroy's Father & Son Construction
5.0(
4
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2006

Free estimates

Credit card accepted

"I worked with Daniel and he was very prompt and responsive, did exactly what he said he'd do. He worked underneath the house in an area I couldn't access. Took and showed me pics to illustrate the issues and he worked excellently."
Response time12 hrs
Response rate95%
1 neighbors recently requested a quote
Avatar for NEXTGEN HOME REPAIR LLC
NEXTGEN HOME REPAIR LLC
5.0(
3
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2024

Free estimates

Offers commercial services

"We hired Nextgen Home Repair to remodel our already converted garage back house so we could turn it into a comfortable living space for a family member. Before the remodel, it technically functioned as a space, but it didn’t really feel livable or welcoming but now it definitely feels like a home!! They fully repaired and updated both the inside and outside of the garage. The interior feels completely refreshed and everything looks clean and brand new. On the outside, the repairs and updates made a huge difference too so it finally looks like it belongs with the rest of the main house. The team was easy to work with, communicated clearly, and made sure everything was done right. You can tell they care about the quality of their work. We’re really happy we chose Nextgen Home Repair."
Final Product
At night
Before
6 neighbors recently requested a quote
Gima Construction
5.0(
2
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2010

Free estimates

Offers commercial services

We're a locally owned and operated company that values honesty, integrity and treats your home as if it were our own. We offer a variety of general Contractor home improvement services that are customizable to each individual project. We specialize in additions and kitchen remodels, but also offer a wide range of expertise for a variety of other projects. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!

Response time4 days
Recommended by100%of homeowners
Avatar for Via Segovia Construction
Via Segovia Construction
5.0(
1
)
Basement - Remodel

Serving Altadena, CA and surrounding areas

Approved

In business since 2015

Offers commercial services

Customers say: Quick response

"My Name is Tony Arredondo, owner of LA Pavers and Construction LLC, LA Smart Home Systems. Kevin has gone above and beyond on executing all of our rendering designs and plans. From our hardscape and landscaping to high end interior Home Theater designs. Never disappoints, highly recommend Kevin for all your high end rendering designs. Thank you Kevin"
Front Entry
Lounge Area
Spa Treatment Room
Loft/Yoga Studio
Restaurant Before

+23

Response time3 hrs
Recommended by100%of homeowners
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Showing 1-10 of 289
FAQs for basement remodeling projects in Altadena, CA

Finishing a basement turns unused square footage into livable space and returns up to 70% of what you spend when you sell your home. Beyond that resale boost, you gain a playroom, home office, or guest suite you can start enjoying right away. That mix of daily comfort and solid return on investment (ROI) makes basement finishing one of the smartest upgrades you can tackle.

In some parts of the country—especially lots on swamps, high water tables, or other wetlands—local codes prohibit basements. Saturated soil puts constant pressure on foundation walls and lets water seep in faster than any sump pump can handle. 

If your property sits on waterlogged ground, building on a slab or crawl space is often safer, more affordable, and code-compliant.

Most basements wrap up in four to eight weeks. Framing takes three to five days, with electrical and plumbing rough-ins following over the next week. Add five days for drywall, two to three for flooring, and another week for paint, trim, and punch-list items. 

Delays can happen if materials run late or your contractor’s calendar is packed, so build in a little cushion when you plan.

Whether a finished basement counts toward your home’s official square footage depends on local rules. Many areas only include below-grade space if it has code-approved egress, fully finished walls, ceilings, and floors, plus consistent heating. 

Check with your local assessor or building department before you start; meeting those standards can affect taxes, appraisals, and resale value.

Building codes require a checklist: dedicated heat and electrical service, a code-approved stairway, and at least one egress window or exterior door. Walls, ceilings, and floors must be fully finished and meet insulation, ventilation, and fire-separation standards. If you add a bedroom, you’ll also need a closet, proper clearances, and safe exits. If you change the layout later, be ready to update the space so every new room still meets today’s code.

The Altadena, CA homeowners’ guide to basement remodelings

From average costs to expert advice, get all the answers you need to get your job done.