TerraFirma

Mercer Island, WA

Foundation, Crawlspace & Concrete Contractors in Mercer Island, WA

Terrafirma in Mercer Island, WA

At TerraFirma, we’re dedicated to protecting and enhancing the structural integrity of homes right here in Mercer Island and throughout Washington. For years, we’ve been helping local homeowners tackle the unique climate and soil challenges of our beautiful region.

From a cracking foundation to a musty basement, a damp crawl space, or an uneven concrete slab, TerraFirma has the expertise, tools, and reliable solutions to restore your home in Mercer Island and ensure it remains safe for years to come.

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Mercer Island’s TOP-RATED Foundation & Basement Contractors

Contact us at (866) 486-7196 or use the form to the right.

Hours: Monday – Friday, 8am-5pm

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    Foundation Repair Mercer Island

    Foundation issues can lead to significant damage to your home if they aren’t dealt with promptly. In Mercer Island, WA, homeowners may observe symptoms like cracks in the floors, bowing walls, and sagging floors, indicating potential structural problems beneath the surface. You might also notice doors that stick, windows that won’t close properly, or gaps appearing between the walls and ceilings. These signs could suggest that your foundation is shifting due to soil movement, water damage, or wear and tear over time.

    At TerraFirma, we specialize in foundation repair on Mercer Island, offering tailored solutions that address the specific issues affecting your home’s foundation. Our process starts with a thorough inspection to identify the extent and root cause of the problem. From there, we recommend one or more of our trusted foundation repair systems:

    Foundation piers

    Our push and helical piers are expertly designed to stabilize and lift your foundation by transferring its weight to deeper, more stable soil. Helical piers are perfect for areas with known soil conditions, while push piers are ideal for locations with uncertain ground stability. Both solutions are minimally invasive and provide lasting results, making them great options for Mercer Island homeowners.

    Wall Stabilization Systems

    For cracked, bowing, or leaning walls, we offer a suite of reinforcement products. These include:

    • CarbonArmor®: Made from fiber-reinforced polymers ten times stronger than steel.
    • PowerBrace®: Zinc-plated steel beams that can be tightened over time.
    • GeoLock® Anchors and Helical Tiebacks: These systems halt inward movement and gradually straighten walls over time.
    • EverBrace™: Designed for severely deteriorated walls, this system replaces and reinforces failing foundation walls with steel supports.

    We also offer grouted micropile tiebacks for difficult soil conditions, SmartJack® crawl space support posts for sagging floors, and vapor barriers to manage humidity and prevent further moisture damage.

    Every solution comes with expert installation, convenient maintenance options, and transferable warranties, ensuring you have confidence and peace of mind in your Mercer Island home.

    Basement Waterproofing Mercer Island

    Don’t let a wet basement ruin your home on Mercer Island. Moisture can lead to mold, mildew, structural damage, and even affect your indoor air quality. Look out for signs of water intrusion like musty odors, stained walls, pooling water, or white, powdery efflorescence that appears when water evaporates. Remember, even a small crack in your basement wall can turn into a big entry point for moisture!

    TerraFirma provides expert basement waterproofing solutions in Mercer Island, ensuring your space stays dry, healthy, and functional—whatever the weather brings.

    We design and install custom drainage systems to redirect water away from your basement and into sump pumps, helping protect your foundation on Mercer Island.

    WaterGuard®: Our most popular system, it’s installed below the floor slab and above the footing to prevent clogging.
    DryTrak®: Ideal for monolithic foundations where jackhammering is not feasible.
    FlowGuard®: A thin-floor drain system used in basements with thin concrete slabs.
    TrenchLock™ Inserts: Block ground air from entering while allowing water to drain.

    We offer several sump pump options tailored to your water exposure:

    TripleSafe™: Three-pump system for maximum protection, including battery backup for power outages.
    UltraSump®: High-capacity battery backup pump that activates when the main pump fails or power goes out.
    SuperSump®: A single-pump system for homes with minor water issues.

    VaporLoc Elite: A heavy-duty wall liner that stops moisture and mold while directing water into drainage systems.
    SaniDry Sedona & XP: Energy-efficient dehumidifiers that remove up to 109 pints of moisture daily, improving air quality and comfort.

    Our SunHouse™ Window Wells and WellDuct® Drains keep your basement bright, dry, and free from debris, while meeting egress codes for safety.

    Waterproofing in Mercer Island, WA, not only safeguards your investment but also turns your basement into a safe, functional extension of your home.

    Crawl Space Repair Mercer Island

    Crawl spaces might be out of sight, but they play a vital role in your home’s structure and air quality here in Mercer Island. If not properly maintained, a neglected crawl space can become a breeding ground for mold, pests, and standing water. These issues can lead to wood rot, unpleasant odors, and even respiratory problems for those living in your home.

    We understand the unique crawl space challenges in Mercer Island, WA. That’s why TerraFirma offers tailored crawl space repair services to tackle moisture, mold, pests, and sagging floors with comprehensive encapsulation, effective drainage solutions, and sturdy structural support.

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    Encapsulation & Drainage

    We begin by sealing the crawl space with our VaporLoc Elite liner, a 120-mil thick waterproof barrier that blocks moisture, soil gases, and allergens. To ensure proper drainage:

    • We use drainage matting under the liner to guide water to your perimeter drain or sump pump.
    • Sump pumps remove water quickly and efficiently, even during heavy rain or high water table conditions.
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    Crawl Space Entry & Vent Solutions

    • EverLast™ Doors & Access Wells: Waterproof, durable entry systems that keep out pests and moisture.
    • Turtl™ Access Well: An attractive, lockable access solution in several colors.
    • Vent Covers: Sealing crawl space vents prevent outdoor air, moisture, and insects from entering.

    Crawlspace repair in Mercer Island is crucial to maintaining your home’s overall health and energy efficiency.

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    Structural Repairs

    To support sagging or weak floor joists, our SmartJack® Support Posts offer adjustable, galvanized steel columns that restore floor stability. These are fast to install and offer permanent results.

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    Dehumidifiers & Monitoring

    Install a SaniDry Sedona dehumidifier to maintain healthy humidity levels year-round. For added security, our ShipShape™ System offers 24/7 performance monitoring, proactive maintenance alerts, and remote control of your crawl space systems.

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    Concrete Repair Mercer Island

    Cracked, uneven, or damaged concrete isn’t just an eyesore—it can pose a safety risk. Issues like poor soil compaction, freeze-thaw cycles, erosion, and tree root growth can cause these problems to arise. That’s why homeowners in Mercer Island trust us to repair their sidewalks, patios, driveways, and concrete slabs quickly and effectively.

    TerraFirma provides quick, clean, and durable concrete leveling and repair services for Mercer Island, using cutting-edge polyurethane foam injection and expert crack sealing.

    PolyLevel® Concrete Lifting

    PolyLevel uses expanding polyurethane foam to lift and stabilize concrete slabs. This non-invasive method is perfect for residents of Mercer Island, WA:

    • Sidewalks – Eliminates tripping hazards and restores smooth walkways.
    • Driveways – Prevents further cracking and improves curb appeal.
    • Patios, Porches, and Pool Decks – Ensures proper drainage and surface stability.

    NexusPro™ Crack & Joint Sealant

    To prevent water intrusion that can lead to further sinking, we apply NexusPro, a UV-resistant silicone-based joint sealant that:

    • Cures in just 60 minutes.
    • Withstands extreme weather and heavy use.
    • Includes color-matched sand for a clean, polished look.

    SealantPro™ Concrete Protection

    After sealing and lifting your concrete, SealantPro provides a long-term barrier against moisture, chemicals, and seasonal temperature changes. It penetrates deep into concrete to resist stains, flaking, and surface erosion.

    We also provide commercial concrete repair in Mercer Island, WA for industrial buildings, warehouse floors, roads, runways, and rail lines—using the same high-quality systems we trust for residential properties.

    Earthquake Retrofitting Mercer Island, WA

    Much of the Pacific Northwest, including Mercer Island, is located in an active seismic zone. Homes constructed before the updated building codes of the 1990s are particularly at risk. Even a minor earthquake can lead to homes shifting off their foundations or suffering significant structural damage.

    TerraFirma’s earthquake retrofitting services help secure your Mercer Island home to its foundation and strengthen its ability to withstand seismic events.

    Retrofitting your home for earthquakes in Mercer Island not only helps you stay safer but can also lead to lower insurance premiums, reduced deductibles, and access to coverage options that may not have been available before.

    How We Retrofit

    Assessment & Planning

    Retrofitting your home in Mercer Island starts with a thorough assessment of its current condition. Our experienced professionals, including structural engineers and certified technicians, will carefully inspect your property to pinpoint any weaknesses and suggest the best solutions for improvement.

    Our evaluation involves a thorough inspection of the foundation, walls, roof, and overall structure. Following this, our engineer creates a detailed retrofitting plan tailored to the findings.

    Foundation Bolting

    Securing the foundation is an important next step here on Mercer Island. Our skilled technicians install anchor bolts to firmly attach your house to its foundation, ensuring stability and preventing any lateral movement during an earthquake.

    Our process involves drilling into the foundation and installing steel bolts. Our team tightens these bolts to reinforce the structure, boosting its stability and making it more resilient against seismic activity.

    Adding Shear Walls

    Shear walls play a vital role in earthquake retrofitting on Mercer Island, helping to distribute seismic forces and keep buildings standing strong during tremors.

    “Shear walls are usually made from plywood or other durable materials and are strategically placed throughout homes, especially in cripple walls. These walls enhance support and stability, helping to minimize the risk of damage during an earthquake, a crucial consideration for residences in Mercer Island.”

    Bracing & Reinforcing

    Next, we’ll enhance and strengthen key areas of your home with steel braces and straps. Our team will install these to essential structural components like the roof, walls, and floors. This step boosts your home’s overall stability, providing a robust framework designed to withstand seismic forces right here in Mercer Island.

    Securing Applicances

    Securing your appliances helps create a safer home for everyone on Mercer Island. Anchoring items like water heaters and refrigerators is crucial. Our technicians also ensure that gas meters are properly protected to minimize the risk of gas leaks.

    Reparing Foundations

    During retrofitting, technicians may notice substantial foundation damage that needs immediate repair. Adding crawl space support posts and foundation piers, and stabilizing the walls are some of the ways TerraFirma can reinforce your foundation.

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    Secure Your Mercer Island Home Today

    At TerraFirma, we’ve spent over 20 years helping homeowners in Mercer Island and across the Pacific Northwest protect their homes from the ground up. From foundation repair and basement waterproofing to crawl space encapsulation, concrete leveling, and earthquake retrofitting, our team delivers top-tier craftsmanship with trusted products, proven systems, and lasting warranties.

    Every home in Mercer Island, WA is unique, and at TerraFirma, we have the solutions to tackle every challenge. Reach out to us today for a free in-home estimate and find out how we can help enhance the safety, health, and value of your home for years to come.

    Mercer Island
    Homeowners
    Frequently Asked Questions

    How does rain put my home at risk ?

    What’s the best way to repair concrete?

    What types of cracks in my foundation or basement should I be concerned with?

    How to fix a leaking basement floor?

    Are you noticing damp drywall and carpet in your basement?

    Which vapor barrier is best for weeping walls?

    Can I turn my crawl space into storage?

    How to repair damaged concrete?

    What is that bad smell coming up from my drain?

    What is the difference between helical piers and push piers?

    How long does basement waterproofing last?

    Need Top Rated
    Foundation Experts
    in Washington?

    Our clients don’t just recommend us—they rave! From Tacoma to Seattle, Olympia to Puyallup, and all across Washington state, our trusted experts consistently provide top-rated, reliable foundation solutions. See for yourself why we’re the preferred choice.

    Bailey Mercer came out on time, which is the number one indicator of professionalism in my experience. He kept the conversation short and to the point. He did not try to upsell me on things didn’t need, and to that point, neither did the sales staff over the phone. Bailey did the measurements, with precision and finished at a reasonable time. I have confidence that when we decide to secure our foundation we will be using Bailey Mercer as our go-to expert when we call TerraFirma.
    TerraFirma Foundation Systems is excellent at basement waterproofing. Be sure to ask about all the available options so you can choose the one that’s right for you. The company is very capable, but it’s important to do your research before making a decision. The crew—Antonio, Jessi, and Casey—worked extremely well together. Antonio is especially sharp; whenever I suggested an idea, he immediately understood what I meant and offered an even better solution on the spot.
    Update: Robert and Jacob showed up and fixed my sagging kitchen floor. Punctual, professional, thorough, fast! Highly recommend TerraFirma to anyone needing foundation services. Overall total experience was top notch!! Thank you TF!! Noah arrived punctually and impressed from the get-go! He was here for an estimate visit and began with the explanation of how the appointment would be performed He was very thorough in explaining every detail and options available to me. Although I have not committed, Noah’s professionalism and knowledge were on point and I am definitely going to consider using Terra Firma for my sagging kitchen floor. Stay tuned…
    We had the pleasure of working with Samuel Bryant, System Design Specialist at TERRAFIRMA, who provided us with a complimentary foundation and crawlspace inspection along with detailed repair estimates. Samuel was highly professional, knowledgeable, and responsive throughout the entire process. He delivered a comprehensive inspection report and repair design that clearly outlined the property’s condition and potential issues. His thorough assessment gave us valuable insight during our home-buying decision and helped us better understand the risks and costs involved. We greatly appreciated the time, expertise, and attention to detail that Samuel and TERRAFIRMA provided. Their excellent service and professionalism left a strong impression on us, and we will not hesitate to reach out to them again for future foundation or crawlspace needs. Highly recommended!
    Just a real pleasure to do business with. The System Design Specialist is very professional. And very thorough. Hailey Newman Is AAA+++ amazing! Everything explained in easy to understand terms. I really could not feel more confident about my issues and my options.
    I met with Noah today, with TerraFirma. He was personable, a good communicator, an excellent listener, patient and knowledgeable.
    We hired TerraFirma to fix our foundation. They inspected thoroughly, explained the plan, and completed the repairs professionally. The process was smooth, and we’re thrilled with the results. Highly recommend TerraFirma!
    Sam was able to provide an excellent inspection and honest report of my crawlspace waterproofing needs. Didn’t feel rushed or pressured. Was able to educate me to better understand the issues and risks. Thank you so much Sam
    Seth has made this process so streamlined and time efficient. I was concerned about my foundation issue, however he was able to assess the issue and present a viable solution with ease. He explained what had occurred and how to fix/ prevent such issues in the future in a way that left me informed and empowered to make informed decisions about going forward. He and his team has been prompt with communications and even sent photo updates of the work being complete, as I was out of town at the time. I really appreciated Seth going out of his way to make this the best experience possible, taking pride in his work and putting in the extra effort.
    Good customer service, good quality work and timely.

    Schedule your free
    Foundation Evaluation

    Schedule your free
    Foundation Evaluation