Helical Anchors For Leaning Walls
The soil around your foundation house often exerts a great deal of pressure on your basement walls. This pressure varies based on the types of soil that are present, how much moisture is in the soil, and how far underground your foundation extends. In Missouri our enemy is the clay based soils.
Since there is constant pressure pushing in on the foundation wall and there is no equalizing pressure pushing out we could have a problem. If the outside pressure is greater than the strength of your walls, they could begin to fail.
Cracks in the concrete or block basement wall are usually the first sign of wall failure. Sections of the wall can actually start to buckle, bow, and lean inwards. Left unchecked, this damage will worsen and can even result in walls that totally collapse. If you have a finished basement you will notice walls getting racked sideways, door alignment issues and celing tile being pushed.
As property owners the good news all of this can be resolved using several methods including helical wall anchors.
Helical Wall Anchors
Many foundation repair companies use a wall anchor system to straighten and/or stabilize bowing buckling walls. Once a series of these wall anchors has been installed, the system can be torque to permantly hold the wall in place.
If you desire to straighten the wall back to its original position then to be sucessfaul the installers will need to dig a trench along your foundation wall down to the footing, install their anchors, gently raise the house, and then pull the wall back. It is also possible to address footing drain issues that may have been the cause of the issue at the same time while the trench is open. Most of the time the clay soil will be hauled off and replaced with gravel to relieve future issues with the foundation.
Helical Anchors are a great solution to bowed or leaning walls in Missouri. These machined anchors are machine drilled past the active zone of moving earth at a downward angle to specified torque to ensure they can provide the support needed. It is possible to stabilize or straighten a leaning wall. If caught early enough stabilize the structure may be the best choice. It is cheaper and less disruptive to your yard and landscape.
Steps For Helical Anchor Installation
- If straightening the wall the process will begin by excavating the soils out from around the foundation.
- Next a small hole in your foundation wall for the helical anchor shaft that will extend from the wall to each helix that is screwed into the ground. The anchor is machine driven through the soil until it reaches proper torque suitable for supporting your wall load and soil.
- At this point, your foundation repair experts will attempt to straighten the foundation walls back to their original position. Anchor plates will be attached inside the basement wall and wall anchors will be tightened and adjusted accordingly and will provide long-term support for the walls.
- Once the wall is straightened, the excavation is filled using the soil removed or a better solution - to avoid excessive soil pressure in the future, gravel and drainage tile may be installed to help avoid soil pressure due to excessive moisture. After backfilling, landscape details will be carefully restored. I would recommend you spend the extra money and replace most of the old soil next to your foundation with clean rock and drain tile.
- The concrete holes will be filled and waterproofed under the wall plates to ensure water doesn't make it's way into your basement.
Advantages Of Helical Wall Anchors
It is our opinion based on years of experience that helical wall anchors while costing more, are a more reliable solution in our Missouri soils. Compared to Earth or Plate Anchors which are sold as solutions frequently around the state, they are a better permenant hands off solution.
- Permenant Solution
- No maintenance required
- Reaches better soil further out and deeper.
- Engineered with safety factors for the structual load.
We have seen many earth anchors fail and dug up and replaced. The engineering supports helical anchors being the best solution. However keep in mind to keep your warranty good you will likely need to keep drainage and gutters properly maintained - which you should do anyway.
How Much Does Leaning Wall With Helical Anchors Cost?
With many building improvements it will vary with several options and conditions. But as a general rule of thumb here is a rough estimate of a bowed leaning basement wall.
40 ft Basement Wall
Spacing will vary but typically every 6 ft. for helical wall anchors. (4 ft if the wall is very bad concrete). If you come off the corner 6ft to start with it should take 6 anchors. If you do the math the last anchor would be 4 ft. from the corner but typically they will move things around and average it out across the wall. The wall is weaker in the middle so they may choose to install them closer together there or add an extra one.
Helical wall anchors will generally run $750-$1000 each NOT including the excavation (digging out the foundation) which many times is priced by the foot. $15-$20 per foot is common to dig out the wall, and replace with gravel. This may sound expensive but keep in mind they are having to truck out the old soil, haul in gravel, etc. The excavation can be the longest part of the job.
So this 40 ft. wall could cost anywhere from $5100 to $6800 and should take 3-5 days to complete. Keep in mind bad weather can change timeframes and make it difficult for access.