TerraFirma Foundation Systems

Sammamish, WA

Foundation, Crawlspace & Concrete Contractors in Sammamish, WA

Terrafirma in Sammamish, WA

At TerraFirma, we’re dedicated to safeguarding and improving the structural integrity of homes in Sammamish and beyond. With years of experience, we’ve helped countless homeowners tackle the unique climate and soil challenges of our 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 Sammamish home and ensure its safety for years to come.

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Sammamish’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 Sammamish

    Foundation issues can lead to significant damage to your home if not taken care of. Signs like cracks in the floors, bowing walls, and sagging floors may indicate more serious structural problems. If you live in Sammamish, WA, you might notice doors that stick, windows that won’t close properly, or gaps appearing between your walls and ceilings. These are all potential indicators that your foundation is shifting due to soil movement, water damage, or natural aging.

    At TerraFirma, we specialize in foundation repairs in Sammamish, offering expert solutions designed specifically for the unique challenges your foundation may face. Our process starts with a thorough inspection to identify the root cause and extent of the issue. From there, we recommend one or more of our trusted foundation repair systems tailored to your needs:

    Foundation piers

    Discover our push and helical piers designed to stabilize and elevate your foundation by shifting its load to deeper, more stable soil. In Sammamish, our helical piers are perfect for areas with known soil conditions, while our push piers excel in locations where soil stability may be uncertain. Both options are minimally invasive and provide lasting solutions for your home’s foundation needs.

    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 professional installation, ongoing maintenance options, and transferable warranties, ensuring you have confidence and peace of mind in your Sammamish home.

    Basement Waterproofing Sammamish

    Living in Sammamish, WA, means enjoying the beauty of nature, but a wet basement can create real headaches. It can lead to mold, mildew, structural damage, and even poor air quality in your home. You might notice signs of water intrusion like musty odors, stained walls, pooling water, or a white powdery residue known as efflorescence left behind as water evaporates. Remember, even a tiny crack in your basement wall can turn into a significant entry point for moisture.

    TerraFirma provides top-notch basement waterproofing solutions in Sammamish, ensuring your home stays dry, healthy, and functional in any weather.

    We design and install custom drainage systems in Sammamish that effectively redirect water away from your basement and into sump pumps, safeguarding your foundation.

    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 Sammamish, WA safeguards your investment while turning your basement into a safe and functional extension of your home.

    Crawl Space Repair Sammamish

    Crawl spaces often get overlooked, but they’re essential for your home’s structure and air quality here in Sammamish. If left unattended, 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 you and your family.

    We understand the unique crawl space challenges in Sammamish, WA, and TerraFirma’s repair services are tailored to tackle moisture, mold, pests, and sagging floors with complete encapsulation, effective drainage solutions, and robust 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 Sammamish 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 Sammamish

    Damaged, cracked, or uneven concrete isn’t just an eyesore—it’s a safety risk. Issues like these can arise from factors such as poor soil compaction, freeze-thaw cycles, erosion, or tree roots. That’s why homeowners in Sammamish turn to us for quick and effective repairs on their concrete slabs, sidewalks, patios, and driveways.

    TerraFirma provides quick, efficient, and durable concrete leveling and repair services right here in Sammamish, WA, utilizing cutting-edge polyurethane foam injection and expert crack sealing techniques.

    PolyLevel® Concrete Lifting

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

    • 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 Sammamish, WA for industrial buildings, warehouse floors, roads, runways, and rail lines—using the same high-quality systems we trust for residential properties.

    Earthquake Retrofitting Sammamish, WA

    Here in Sammamish, we live in an area of the Pacific Northwest that’s part of an active seismic zone. Homes built before the updated building codes of the 1990s may be particularly at risk. Even a minor earthquake can cause a home to shift off its foundation or sustain significant structural damage.

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

    By retrofitting your home for earthquakes in Sammamish, you can not only enhance its safety but also potentially reduce your insurance premiums and deductibles, plus qualify for coverage that might not have been available before the upgrade.

    How We Retrofit

    Assessment & Planning

    In Sammamish, the retrofitting process starts with a thorough assessment of your home’s condition. A qualified expert, like a structural engineer or a trained technician, will inspect the property to pinpoint any weaknesses and suggest the best solutions to enhance its safety and performance.

    Our evaluation covers the foundation, walls, roof, and overall structure of your home in Sammamish. Based on our findings, our engineer will create a detailed retrofitting plan tailored to your needs.

    Foundation Bolting

    Securing the foundation is the next step in our process here in Sammamish. Our technicians will install anchor bolts to connect your home to its foundation, ensuring it stays stable and secure during an earthquake.

    This process involves drilling into the foundation and inserting steel bolts. Our team then tightens the bolts to secure the structure, improving its stability and helping it withstand seismic activity.

    Adding Shear Walls

    Shear walls play a vital role in earthquake retrofitting, helping to distribute seismic forces and keep your home safe from collapse.

    Shear walls are usually made from strong materials like plywood, and they’re strategically installed in key areas of your home, especially in cripple walls. These walls offer extra support and stability, helping to minimize the risk of damage during an earthquake.

    Bracing & Reinforcing

    Next, we enhance the critical areas of your Sammamish home by adding steel braces and straps. Our skilled team installs these reinforcements to essential structural components like the roof, walls, and floors. This process boosts your home’s stability, creating a strong framework that can better handle seismic activity.

    Securing Applicances

    Ensuring your appliances are secure helps create a safer home for everyone in Sammamish, WA. It’s important to anchor items like water heaters and refrigerators. Our technicians can also install protective measures for gas meters to reduce 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 Sammamish Home Today

    At TerraFirma, we’ve spent over 20 years helping homeowners in Sammamish 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 Sammamish, WA has its own unique qualities—but at TerraFirma, we have tailored solutions for 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.

    Sammamish
    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 was the best! So knowledgeable and helpful! Also, very understanding & caring! So good at what he does!
    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.
    Bailey did a fantastic job inspecting my crawl space and designing a solution that fit my needs. I really appreciated his thorough evaluation, detailed explanations, and professionalism. I will keep TerraFirma in mind for future projects.
    We were concerned that our foundation was uneven. Tulane came out, thoroughly inspected our home and confirmed we had uneven flooring/ foundation issues throughout our house and garage. He offered us a few different resolutions and was super informative about what to expect. We chose to proceed and address the issues. Bree reached out and was super helpful with scheduling and even accommodating us when we had to reschedule. Robert came out today, explained the process, then got started to work. He was super respectful of our property and worked so efficiently he was able to get the job completed in 1 day vs 2 days. Terrafirma was able to resolve all of our issues & was super easy to work with! Thank you again
    Seth, awesome job on lifting my garage floor… it’s been a few months now and everything is looking great. Would recommend Seth on any job site, his professionalism and expertise can’t be ignored… Thanks James
    Robert and Jacob came out on a cold, breezy December day and injected the company's foam-brew under our one-hundred-year-old staircase, raising it nearly 1 inch and thereby reconnecting it to our home! No small feat! As a realtor who has recommended TerraFirma to several of my clients, I've come to expect this kind of service, but I wanted to call out the guys for their professionalism and resolve when rain threatened. They also had great info (pics, measurements, etc.) from the estimator, making the project well-organized and timely. Well done!! Highly recommend.
    Quoted me $80k for proprietary solutions to some problems I do have, and some I don’t actually have. Took a bunch of pictures, showed them to me, but conveniently never sent them to me and thought it was weird I asked for the proposals to be emailed to me.

    I decided to get a few other opinions and boy am I glad I did. Lying to me is one thing, but doubling down on the phone when you call me to ask if I’ve had time to consider scheduling the work is another.

    I vote with my wallet and I have zero respect for a company that uses scare tactics or attempts to fudge the truth when they think the consumer isn’t educated enough on the subject to put two and two together.

    Being a homeowner is hard and expensive enough… but then you have to navigate whether or not someone is trying to help you or empty your wallet for commission. This was arguably a worse experience than being a woman at the car dealership. No, I am not interested in purchasing blinker fluid…

    Edit: With a continuous improvement mindset, I do appreciate someone at Terra Firma reaching out to me directly to understand the details of my experience so they could work to resolve internally.
    Great expedience, very knowledgeable and helpful .
    Hey Folks, So just over a year ago we were having some issues at the house, I wrote to all of you on how wonderful TerraFirma was to us and I am here to tell you... THEY DID IT AGAIN! I starting noticing some movement in the driveway and inside the garage again. Called up Bree in the office and asked to have someone come take a peek. Edwin came out, what an awesome dude! Edwin spent a short time at the house remeasuring a couple things to compare back at the office with measurements from a few months ago, We heard from Bree that the measurements were still within reason. I let Bree know, something is not sitting well with me and I really would like to chat with the Mgr. So I received a call from Tulane, Again SUPER DUDE! Tulane assured me with my husband present that I am not being in any sorts a pain, I have concerns and he and Sam, who came out in 2024 will come to the house.

    Well they came, they saw, Oh Boy! I was not wrong, they were here 2.5 hrs and again, the house has had some movement and we need some more work to stabilize. We have some additional C.Y.A's to add to this round, as our neighborhood and home has lots of sand in the soil so we are going to be looking into getting a GEO Engineer out to see what is causing the movement.

    I give all the back info, because I want you all to know, if you feel something is not right CALL and have your home looked at. TerraFirma is NOT redoing what they already did, this is all new issues, not their fault at all... Tulane and Sam are amazing, they took the time to explain and give us all options. The info they share through experience and knowledge is beyond me and it is so appreciated.

    If you have any foundation, sinking driveways, walkways, stairs, cracking in your walls, around windows, doors.... Call these guys!
    I hands down don't always do reviews but I do for these guys because they deserve to have their names out there so you know they are TAKING CARE of their customers the whole way through! 10/10 and then some.... THANK YOU!
    Bailey came out to do an inspection of our foundation to let us know what shape it was in and what kind of work might need to be done. He was thorough and honest about the condition of our foundation so we could make informed decisions about next steps with our property.

    Schedule your free
    Foundation Evaluation

    Schedule your free
    Foundation Evaluation