House Foundation Repair & Basement Waterproofing in Longmont, CO

Does your home or commercial property have bowing foundation walls, sinking concrete slabs, or leaky windows in the basement? There is no reason to worry — Thrasher Foundation Repair is your trusted expert, providing solutions for these problems and so much more since 1975.

Contact Thrasher Foundation Repair to schedule a free inspection and cost estimate on any of our reliable services, including basement waterproofing, foundation repair, crawl space encapsulation, and concrete repair. We proudly serve Longmont, CO and nearby areas.

Testimonials From Longmont
Very grateful for the Thrasher team! Very impressed with their level of professionalism and their execution...
Testimonial by Jeremy L. from Longmont, CO
I can not express my gratitude enough! Thrasher was so professional and it is obvious they care about they...
Testimonial by Larry A. from Longmont, CO
The project went well and Dakota did a great job!
Testimonial by Gary D. from Longmont, CO
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Durable home foundation repairs in Longmont

No matter how small the foundation damage may seem, problems can worsen and impact other areas of a home or building, leading to issues like sticking windows and doors, cracked drywall, a tilting chimney, and moisture intrusion. From cracked foundation floors to bowing basement walls and foundation settlement, Thrasher Foundation Repair provides permanent solutions for these structural problems and more.

Home Foundation Problems We Fix:

  • Foundation settlement & sinking
  • Sticking windows & doors
  • Tilting chimneys
  • Tilting & bowing walls
  • Cracked foundation walls & floors
  • Collapsing retaining walls
  • Sagging crawl space
  • Uneven floors

Our House Foundation Repair Products:

  • Crawl space support posts
  • Push piers & helical piers
  • Wall anchors
  • Street creep repairs
  • Foundation wall brace & beams
  • Carbon fiber wall straps
  • Foundation settlement repair
  • Foundation crack repair

Schedule a free foundation inspection and service estimate to get personalized repair solutions for your property. We proudly serve Longmont and nearby areas in Colorado.

Lasting basement waterproofing system in Longmont

If your home or building has leaky egress windows, damp walls, excess condensation, mold, or other moisture intrusion problems, contact the basement waterproofing experts at Thrasher Foundation Repair.

We can eliminate basement flooding and leaking with a patented waterproofing system customized to suit any property, creating a dry below-grade space and keeping it that way for years to come! We proudly serve Longmont and nearby areas in Colorado.

Schedule a free basement waterproofing inspection and service estimate to learn more. We proudly serve Longmont and nearby areas in Colorado.

Our basement waterproofing system includes:

  • Interior drainage systems
  • Sump pumps
  • Replacement egress windows
  • Window wells
  • Mold treatment
  • Dehumidifiers

Crawl space repair & encapsulation services in Longmont

Do you have a musty, wet, and humid crawl space in your home or building? Don’t deal with the mess on your own. Contact the crawl space encapsulation and repair professionals at Thrasher Foundation Repair! We provide a suite of crawl space solutions designed to create a drier, more secure area, including a moisture-proof vapor barrier, crawl space doors, crawl space support jacks, and more.

Concrete repair & concrete leveling experts in Longmont

If you’re tired of sinking, cracked driveways, pool decks, sidewalks, or other concrete slabs around your property, contact the concrete repair professionals at Thrasher Foundation Repair. We offer simple, innovative solutions that are far superior to the standard mudjacking or concrete replacement. Our cracked concrete repair, concrete leveling, and concrete sealing systems install with no mess and no stress. Plus, they are quick to cure, so you can use your slabs soon after installation.

Never worry about UV rays, debris, gas, water, or other liquids ruining your slabs. Our solutions are incredibly durable and address the underlying cause of concrete damage, meaning you get lasting results that save you money!

Schedule a free concrete repair estimate to learn more. We proudly serve Longmont and the surrounding areas.

Our concrete repair solutions:

  • PolyLevel®® concrete leveling
  • NexusPro™ cracked concrete repair
  • SealantPro™ concrete sealing
  • Commercial concrete repairs
  • Driveway repairs
  • Pool deck leveling
  • Sidewalk repairs
  • Step repairs

The Thrasher Difference.

No matter the job - we aren't going to feel good about the hard work we've done until you're happy. So we'll do it right or make it right. That's the Thrasher promise.

For the last 45 years in the basement and foundation repair industry, we've focused on the value of doing whatever it takes to get the job done and "wow" our customers every step of the way.

Explore The Thrasher Difference

Before and After Pictures from Longmont
Foundation Repair in Longmont, CO

Foundation Repair in Longmont, CO

Before After
Foundation Repair in Longmont, CO Foundation Repair in Longmont, CO

Jeremy met the Thrasher team at a home show a few months ago. He was interested in purchasing a home but knew it had structural issues. He wanted a professional team to look at the house to figure out what was needed to achieve stabilization for the house to pass inspection. 

We sent Anthony Salcedo to the home to look at the foundation. He found that an area of the foundation was settling about an inch into the soil. Anthony knew we needed to develop a solution quickly because Jeremy had a small window before closing on the house. 

Our install team was able to lift the house about an inch (to its original position) and close most cracks in the walls by installing helical piers. Helical piers are made of heavy-duty galvanized steel that's resistant to bending. They are advanced or screwed into the soil and support the structure's weight.

Jeremy was very grateful throughout the entire process and impressed with our level of professionalism and execution. Above all else, he was happy we were able to work with him on his schedule and close on his new house in time!


Water in Garage Fixed in Longmont, CO

Water in Garage Fixed in Longmont, CO

Before After
Water in Garage Fixed in Longmont, CO Water in Garage Fixed in Longmont, CO

Our customer had a problem with water flooding their garage. The garage turned into a mini swimming pool, and they were tired of trying to push the water out. They asked Thrasher for help to solve this issue.


The problem was that the garage wasn't built properly. When the concrete was poured, it made a bump that didn't let the water drain correctly. This caused our customer's things to constantly get wet. 


So, our team came up with a clever plan. We lifted the concrete floor in the garage using Polylevel foam. This made a gentle slope inside the garage, so the water would flow to the middle and could drain out. 


By changing the concrete floor, we made our customer's garage a dry and welcoming place. Now they don't have to worry about their things getting wet. If you ever have water problems in your garage, give us a call at . 






Support Beam Structure Repair in Longmont, CO

Support Beam Structure Repair in Longmont, CO

Before After
Support Beam Structure Repair in Longmont, CO Support Beam Structure Repair in Longmont, CO

These homeowners recently bought their home and planned to start remodeling it soon. Before their remodel however, they noticed that there were unlevel floors on the second floor. Wanting to ensure that everything would go well with the remodel, they called us.

We sent System Design Specialist Anthony Salcedo to inspect the upstairs floors and determine what the cause of this issue was. Anthony sound that the support beam in the basement has sinking issues and that the floor had heave issues. He found the root cause of this problem to be that the support posts holding up the support beam was failing and needed to be replaced. Anthony and his team got right to work after discussing with the homeowners the best course of action. The team installed SmartJacks and expansion joints to support the basement support beam and ensure that the posts would not move even if the support beam were to heave or sink. This combats the sinking problem, so that the upstairs floor will remain level in the future.

The homeowners were happy with the outcome and the look of them. They can't wait to proceed with their remodel. Check out their support beam lift!

Recent job requests in Longmont, CO

Neighborhood: Lincoln Street, Longmont, 80501

Seal cracks in crawl space, fix metals, and seal off crawl space

Neighborhood: Bluebird Dr, Longmont, 80504

The sidewalk in front of my driveway has been settling and slopes down from the gutter. This ends up creating ponding of water in the winter and creates an ice rink. I am hoping you can raise the sidewalk and lower part of the driveway to a slope that drains again.

Neighborhood: Water Cress Ct, Longmont, 80504

Egress window detaching from foundation. Sinking around window. Water seeping into basement

Neighborhood: Longmont, 80501

Service: Crawl space problems

Neighborhood: Longmont, 80504

Our driveway has settled, the walls have settled some too and cracking the brick siding. Maybe small leaks in the basement. Think the foundation is still ok. Looks like concrete needs lifted and maybe cracks sealed...I need a pro to come look see and help me with a plan to fix what's going on. Thank you, Chad

Neighborhood: Longmont, 80503

I am looking to upgrade my sump pump system and find out what else I can be doing to prevent mold and mildew in basement. My sump runs 24/7 during the flood irrigation months in the summer and I need to be sure it

Neighborhood: Lincoln St, Longmont, 80501

In one corner of the basement water is seeping through from a break in the bricks outside the home. Water is also entering the sun room near the same spot.

Neighborhood: Sunset Street, Longmont, 80501

Front porch issue

Neighborhood: Longmont, 80504

Service: Foundation cracks or sinking

Neighborhood: Penhurst Circle, Longmont, 80504

Sidewalk on the side of my house has sunk in a couple of slabs. It is poured up against the house foundation. A small crack along the wall allowed some water to come into my crawlspace. I'd like to see if your system is more cost effective and a different alternative to new concrete (the slabs dropped at the stress point lines and are still in good shape).

Neighborhood: Roadrunner Ave, Longmont, 80504

Crack forming in driveway and steps. Joshua Camacho was working on my neighbors driveway and gave me a card.

Neighborhood: Snowmass Place, Longmont, 80504

Driveway cracks and movement

Neighborhood: Longmont, 80504

Neighborhood: Spruce Ave, Longmont, 80501

Probably need piers/piles and around full perimeter of house and garage.

Neighborhood: Elmore Rd, Longmont, 80504

Installation of sump pumps and some concrete lifting for patio and sidewalk.

Neighborhood: Mt Arapaho Cir Frederick, Longmont, 80504

Driveway has settled

Neighborhood: Bountiful St, Longmont, 80504

Water is leaking into the basement from one of our window wells during heavy rain. It pools in the middle of the floor and there isn't a proper drain in the basement floor.

Neighborhood: Corey St, Longmont, 80501

The contractor did not pack the dirt enough when they built our basement. The sidewalk we poured outside now doesn't have enough dirt under it and water is going under it into the basement.

Neighborhood: STRATFORD LN, Longmont, 80503

Sloping kitchen floor from original house and addition. Crawl space below addition.

Neighborhood: Lincoln Cir, Longmont, 80501

Foundation cracks inside and out.
Job Stories From Longmont, CO
Water Pooling on Concrete - Longmont, CO

These homeowners recently purchased a home and were having concerns with the driveway sinking towards the house. They were worried about rain and snowmelt pooling near the foundation, which could cause future foundation problems. They wanted a company that knew how to fix their problem, used quality materials, cleaned up after themselves, and offered great warranties - so they called Thrasher! One of our System Design Specialists, Rob Griffin, came out to meet with them. After the inspection, Rob found that due to poor soil compaction and water over time, the concrete in and around the garage has sunk towards the home. Rob proposed we use our PolyLevel to lift and level the concrete, NexusPro as a caulking to seal in-between the slabs and cracks, and SealantPro to extend the lifetime of the concrete. While out on the job, the crew noticed a dysfunctional downspout, which was a key issue the concrete failed the first time. Before the crew left, they fixed this downspout to ensure the homeowners were as taken care of as possible! The homeowners were so happy with the work, and could tell that Thrasher did care about the work we were doing for them. There is no doubt that they are done spending their time worrying about water damaging their concrete and foundation! 

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