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Find Basement remodelers in Mercer Island

Avatar for Topaz Remodeling, Inc.
Topaz Remodeling, Inc.
5.0(
108
)

Serving Mercer Island, WA and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2014

Free estimates

Emergency services offered

"Renovating a home can be stressful, but this team made the entire experience smooth and exciting. They truly listened to what we wanted and helped bring our vision to life. Every room feels thoughtfully designed and carefully built. The attention to small details, the clean job site, and the respectful attitude of the crew made such a difference. Walking into our "new" home for the first time after the renovation was an emotional moment. We couldn't be happier with the outcome and are so grateful we chose them. "
Kitchen Remodel
Bathroom Remodel
Kitchen Remodel
Bathroom Remodel
Kitchen Remodel

+53

Response time10 hrs
Response rate98%
158 neighbors recently requested a quote
Gold Remodeling Inc
5.0(
121
)

Serving Mercer Island, WA and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2017

Free estimates

Emergency services offered

"Gold Remodeling finished our basement remodel a few weeks ago and we?ve already had friends over asking who did the work. The transformation is kind of crazy. What stood out most to me was how approachable the team was, never felt like I was being brushed off when I had questions. We?re in Seattle, so dealing with older homes can be tricky, but they seemed to know how to handle everything that came up. End result feels high quality and functional, not just ?nice looking.?"
My Jobs
My Jobs
My Jobs
My Jobs
My Jobs

+1

Response time2 days
3 neighbors recently requested a quote
Avatar for Johnson Custom Builders
Johnson Custom Builders
5.0(
62
)

Serving Mercer Island, WA and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2011

Free estimates

Warranties offered

"Since I now need to use a wheelchair, several doorways in my home needed to be widened. Two exterior doors had to be replaced, one of which also had to be changed to open out rather than opening in. I hired Johnson Custom Builders and was absolutely delighted with their work. They were always professional. They laid or hung plastic sheeting to contain the dust they created, then at the end of the day they ran the vacuum and even mopped the floor! They were respectful of me and my home. Their work was excellent. One of the things I most appreciated was Ryan Johnson's communication with me before, during, and at the conclusion of the project. He listened to what I needed and then figured out how to make it happen. I recommend Johnson Custom Builders highly!"
Remodeling - General Project
Remodeling - Kitchen & Bathroom Project
Remodeling - General Project
Remodeling - Kitchen & Bathroom Project
Remodeling - Kitchen & Bathroom Project

+75

Response time11 hrs
6 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for BB-Builders-Pro LLC
BB-Builders-Pro LLC
5.0(
37
)

Serving Mercer Island, WA and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2000

Free estimates

Credit card accepted

"Our two bathrooms were remodeled by BB Builders Pro, who worked carefully with us and went above and beyond to ensure our satisfaction. Highly recommend them for any remodeling services!"
design rendering
design rendering
design rendering
design rendering
Approved floor plan

+50

Response time9 hrs
Response rate99%
120 neighbors recently requested a quote
Avatar for Anyvision Home Remodeling
Anyvision Home Remodeling
5.0(
14
)

Serving Mercer Island, WA and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2016

Free estimates

Warranties offered

"Anyvision and Chase were excellent! Their bid was competitive, and their contract was clear and straightforward. What began as a simple shower pan repair turned into a full master bath remodel and a new roof due to water damage. Having dealt with poor contractors for 45 years, we feared the worst, but Chase handled everything seamlessly. He assessed the damage, adjusted the plan, and had the skilled crew to execute both repairs and high-quality finishes. The team was punctual, professional, and kept our home clean. Chase’s tile specialists did exceptional work—no metal edges, just beautifully mitered finishes. With the remodel being unexpected, we had to make quick decisions, but Anyvision’s designer and CAD renderings helped us visualize everything. Chase was onsite daily, keeping us informed with updates, photos, and videos. Challenges arose, but Chase managed them like a pro—offering smart design input, controlling costs, and maintaining quality. This was the best contractor experience we’ve had in the PNW. Anyvision is the real deal, and we’d hire them again in a heartbeat. Their communication, expertise, and customer-first approach set them apart"
Remodeling - Kitchen & Bathroom Project
Kitchen remodeling
Bathrooms remodeling
Home remodeling
Remodeling - Kitchen & Bathroom Project

+187

1 neighbors recently requested a quote
Recommended by100%of homeowners
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FAQs for basement remodeling projects in Mercer Island, WA

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 Mercer Island, WA homeowners’ guide to basement remodelings

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