“Tell me of this drilled pier foundation repair that you speak of . . . I want to know what to expect in my realm on this joyous occasion,” said no one except for me . . . like, just now. Your home is your kingdom though, and you want to know what goes down in it.
Foundation repair isn’t an everyday experience for most people. Lucky for you, it IS an everyday occurrence for Anchor Foundation Repair. We have inspected and repaired thousands of foundations in the Brazos Valley in the last 35+ years. We can definitely share the step-by-step process in a typical drilled bell-bottom pier foundation repair with you.
We will review the 4 usual *for-sure* steps a foundation repair contractor goes through using the drilled pier method to raise and level your home’s foundation and correct a foundation settlement problem. Here’s a preview:
- Work Phase 1: Dig – Drill – Pour
- Concrete Curing
- Work Phase 2: Raising and Leveling
- Work Phase 3: Mud-Pumping and Finish Work
This will be the quick-overview version so that you can get back to your more pressing royal ventures . . . like watching Netflix . . .
Defining a Typical Foundation Repair and the Drilled Pier Method
A normal sort of foundation repair involves adding supports around a portion of the perimeter of a home. With the drilled pier method, piers are installed every 7 linear feet under the outside edges of the home that are experiencing signs of foundation problems.
Around 90% of homes need just these perimeter supports, while 10% of homes also need supports added underneath the interior of the home. This is called interior pier work and since it only applies to 10% of cases, we won’t consider that to be a *typical* foundation repair project for the moment.
So, all the work on a typical foundation repair will be conducted outside of the castle . . . er, I mean home, for the most part, no interior piers are installed and workers stay outside most of the time (except during one step).
Drilled piers are constructed by hand on-site. They are not prefabricated, which makes them different from other methods of slab-on-grade foundation repair, like the pressed piling method. Drilled bell-bottom piers do take longer than other methods because of this *made on-site* feature. You will see why in the 4 steps we describe below.
4 Steps in Drilled Bell-Bottom Pier Foundation Repair Process
These four steps detail the usual steps any foundation repair contractor would perform in the installation of drilled bell-bottom piers. This is our chosen method of repair as we feel it is a great fit for many homeowners who want the best value, stability, and longevity of repairs for their homes.
Our method and process description has much more detail to it and we do things that others may or may not. We’re not talking about *our way* specifically in this article though. Here we are just covering the basics that would apply to any company.
1. Work Phase 1: Dig – Drill – Pour
The first step in installing drilled bell-bottom piers is a lot of digging. The repair crew will be digging a 2-foot by 2-foot hole at each pier location. This is usually done with shovels and wheelbarrows and lots of people digging holes at the same time. These square holes will be dug down about 3 to 4 feet or so and then they will stop and move to the next part of this phase.
After the 2’ by 2’ holes are completed, then the team moves to drilling out straight shafts down from the center of each hole. Each shaft is drilled down about 10 to 12 feet in this area, although in another area of the state or country it might be more or less.
At the bottom of each shaft, a “bell” shape is cut out into the ground making a wider base at the bottom of the shaft. The widest part at the bottom of the bell has a diameter of 24 inches. This feature is where the name bell-bottom pier comes from.
The wider base at the bottom is intended to resist uplift from expansive clay soils and also anchors the pier into the ground for the greatest stability.
So now you have a hole in the ground that is shaped like a cube on top (the pier cap), then a thinner long shaft, and then a bell shape at the bottom. This entire hole is filled up with poured concrete to make a pier that is one solid piece. The concrete piers are also reinforced with steel rebar inside the middle.
2. Concrete Curing
After all the concrete is poured into each pier location, it has to dry and cure for strength. The foundation repair contractor will allow the concrete to dry for at least 7 to 10 days, maybe more if it is a heavier home.
During the concrete curing period, there are no workers on site. You have a little break in the work being done on your home of about a week or a tad more, so the kingdom will be quiet.
3. Work Phase 2: Raising and Leveling
After the concrete has cured sufficiently, the repair team will return to your home to finish the work. The next step is raising the home and leveling it back to its original elevation. Some sections of homes need to be raised an inch or two, while others might need to be raised 5 inches or more in some areas.
Hydraulic bottle jacks are placed on top of each pier location to raise the home. Each jack is small but very powerful and can lift up to 20 tons.
During this process, crew members will need access to the interior of the home to track the progress of raising and leveling. They are checking for cracks in walls to close up, doors to return to functionality, and to ensure that the home doesn’t get raised beyond what it should.
Once the home is where it needs to be, the home is secured in position using steel shims that are pounded into place between the top of the pier and the bottom of the home.
4. Work Phase 3: Mud-Pumping and Finish Work
Now the home is in position and the project is nearing completion. Sections of the home have been raised and now a bit of space exists between the ground and the bottom of the foundation. This is called a void under the home and the empty space leaves the home unsupported in those areas unless it is filled in with something.
Mud-pumping is a process used in bell-bottom pier repair to fill in all that empty space that now exists under the home. A mixture of topsoil, Portland cement, and water are combined to make a flowing mud-like material called slurry.
The slurry is pumped under the home using pipes and a pumping machine. Every tiny space under the home is filled completely with this pressurized slurry material that dries to a sandstone-like consistency. Mud-pumping locks the foundation repair in place and provides extra strength, stability, and holding power for the piers and your raised home.
Mud-pumping the void under your home minimizes the opportunity for future settlement by taking up all the empty space created by lifting the home. It provides continuous support underneath the slab foundation surface.
Then it’s time to finish up and clean everything up and put your yard back in order, turning your home back into your refined and peaceful kingdom.
How Long Does Drilled Pier Foundation Repair Take?
These four typical steps in drilled bell-bottom pier foundation repair do take a bit of time. Piers constructed on-site take time, with all the digging, drilling, and pouring going on. Then the curing process adds a chunk of time as well, which is not involved in other foundation repair methods.
Going through all four steps to complete this method of foundation repair takes approximately 3 to 4 weeks. On weekends no one will be working on your house so it’s just weekdays that things are going on.
Check out this article that gives further detail on how long foundation repair takes with Anchor if you are interested in more whys and hows, as well as our special features.
How Does it Compare to Other Methods of Foundation Repair?
Throughout this article, we mentioned *other methods of foundation repair* and what we’re talking about primarily is the concrete pressed pile method of repair. Pressed pilings are commonly used in our area of Central Texas.
At Anchor Foundation Repair, we don’t use the bell-bottom pier method because we like how long it takes to install. We use it because we think it’s a great fit for homeowners interested in maximum stability and longevity for their home’s foundation. We’ve been using it since 1985 and have a great reputation in the community in doing so.
Want to know how long the drilled bell-bottom pier method compares to installing pressed piles now? Good question. We have an article that gives you the rundown in, “How Long Does Foundation Repair Take? Pressed Piles vs. Drilled Piers.”