Posted by Craig Milam on Mon, Feb 08, 2010 @ 06:30 AM
Drilled bell concrete piers are a common method of foundation repair, but are actually best suited for newly constructed homes and structures. The installation of bell bottom piers in previously existing structures presents a myriad of problems.
First, let's take a look at how Drilled Bell piers are installed in a house. Shafts are dug diagonally underneath a home's foundation from the exterior of the structure. Once they reach the appropriate depth, either stable soil or bedrock, the bottom of the shaft is widened using special bits to create a bell shaped "foot". The shaft is often reinforced with steel rebar before concrete is poured into it (further reading). Once the shaft is filled with concrete, the concrete must cure for 1-2 weeks. Upon completion of curing, the house is lifted and placed on top of the Drilled Bell piers.
Now that we understand the process let's take a look at the numerous disadvantages of this method:
- First, an enormous amount of excavation is required and the excavated soil must be redistributed somewhere.
- In order to drill underneath the house heavy equipment will be placed next to the home causing considerable disturbance to adjacent landscaping.
- Also the vibrations of the drills, depending on their intensity, can cause foundations to crack further.
- Water may seep into the shafts before the concrete is poured causing the bell foot (the support) to be compromised. Any water seepage must be addressed before the concrete can be poured.
- The presence of toxic or flammable gasses may prevent thorough inspection of the shafts (book: Design of Foundation Systems).
- Upon curing of the concrete, pressure is applied, usually using bottle jacks, to the outter edges of the foundation to lift the structure up onto the piers.
- It is not possible to install interior bell piers on existing structures.
- The process takes 2-3 weeks before it is completed
So it is easy to see that drilled bell concrete piers installed in existing structures are not a viable option of foundation repair. If your home or business was built on top of belled piers, you will have adequate support.
In comparison, Superior's Steel Pier foundation leveling process requires minimal excavation, no curing time for concrete, the installation usually lasts no longer than 3 days, can be installed in the interior of the house, does not depend on soil for support, and causes minimal distubance to landscaping around the house. Because our steel piers reach all the way to solid bedrock, your home is protected against the effects of expanisve soils prevalent in our area of Central Texas, thus effectively counteracting the most common cause of foundation problems in our area.
Further Reading on Drilled Bell Concrete Piers:
myfoundationrepair.com
foundationdoctor.info
theconstructor.org
Posted by Craig Milam on Tue, Jan 26, 2010 @ 06:00 AM

Superior Foundation Repair will be examining
disadvantages of various foundation repair methods, over the coming weeks, with an in depth look at why these methods are inferior to Steel Piers. The first type of foundation repair we will expose is the often used method of concrete pressed pilings.
Disadvantages of Concrete Pressed Pilings
In homes with Simple Pressed Concrete Piling Foundation Repair, concrete cylinders are driven underneath the home's foundation one on top of the other using the weight of the slab to press them down until they cannot go any further (known as the point of resistance). Unfortunately, it is impossible to tell what this point of resistance is, it could be bedrock, stable soil or unstable soil. Most engineers agree this method of Foundation Repair is not the correct solution for foundation problems because expansive soil will continue affecting pilings after installation. When the soil expands it can work it's way in between pilings and completely nullify the support this method is intended to provide (see picture above for example of piling displacement).
There is no factor of safety built into Concrete pressed pilings
The factor of safety is defined as "the structural capacity of a system beyond the applied loads or actual loads" by Wikipedia. Because the weight of the structure is used to press the pilings down until they can go no further, simple concrete pressed pilings have a factor of safety ratio of 1:1 which means any significant weight additions, have a great potential to cause foundation instability. According to Wikipedia: "Buildings commonly use a factor of safety of 2.0 for each structural member." This means foundation piers should be able to support the sturcture's weight times 2 at the least. Superior's Steel Pier Method supports a structure's weight comfortably with a safety factor significantly greater than 2 by anchoring the structure to solid bedrock, which prevents future additions in weight to a house, i.e. add-ons, new furniture, etc, from causing any negative affect on a home's foundation. Superior's Steel Piers are Engineer certified.
Pressed Pilings installed in dry or unstable soil may sink upon the introduction of moisture.
Because Texas experiences long periods of dry weather followed by wet weather, the soil moisture content is continuosly changing, causing expansion/contraction of soil (further reading: Article from Geology.com, Blog post on Expansive Soils in Texas, Article from USinspect.com). Therefore pressed pilings inserted into dry soil are unstable from the start. If the point of resistance is on unstable soil, increased moisture can cause the piers to sink further into the ground, or, if the soil is stable, expansion will cause the piers to move.
Oftentimes companies will pre-soak the soil to drive the pressed pilings as deep as possible. This is to prevent the pilings from sinking in times of increased rainfall. Introducing large amounts of water into soil is not good for any home at any time, under any circumstances. Superior's Galvanized Steel Piers are driven through the soil until they reach the bedrock up to 100 feet below the surface, effectively securing a home's foundation to a solid rock, which is unaffected by shrinking and swelling.
Further Reading:
An excellent article on the disadvantages of Simple Pressed Concrete Piers from myfoundationrepairs.com
Posted by Craig Milam on Mon, Jan 11, 2010 @ 11:10 AM
This blog post will examine some of the factors that contribute to how foundation repair estimates are priced and educate homeowners about how foundation repair estimates are formulated.
- The extent of deviation
Deviation refers to the extent that a structure is unlevel. If the home is experiencing severe signs of foundation problems, such as bowed walls, large cracks in the ceiling or walls, or doors that will not open or close properly in a majority of the house, it is feasible that the foundation will need to be stablised with interior piers to a greater extent than houses with a lesser deviation. The more stabilization a house needs, the more the repairs will cost.
- The stability of the soil
In Texas, houses situated atop a great amount of unstable soil tend to need more interior piers to counteract the shrink-swell characteristics of soils. Each house sits on a unique mixture of soils and some soils have greater shrink-swell potential than others (read our article about soil types in Central Texas). Another factor that contributes to the stability of the soil is proper drainage. Improper drainage can cause erosion underneath a stucture which will adversely affect the foundation, and cause it to sink. Naturally if the drainage problem is affecting the entire structure. More interior piers will be needed to counteract the erosion.
- The size and weight of the structure
Other major factors in determining the cost of foundation repair are the size and weight of the structure. Heavier structures will need more piering closer together to adequately support the weight of the structure. The size of the ground floor of a structure also contributes to the amount of piering that will be needed to adequately solve foundation problems. Larger homes will need more piers to provide support over a wider area.
Contact Superior Foundation Repair today for a free estimate on repairs. Superior's Steel Piers are engineer certified and all foundation repair work is back by a lifetime transferable warranty.
Posted by Craig Milam on Mon, Dec 07, 2009 @ 07:53 AM
Overwatering
Overwatering a lawn is a common cause of foundation problems in areas with Vertisols (Expansive Soils).
A frequent source of damage is the differential swelling caused by pockets of moist soil adjacent to dry soil. For example, lawn and garden watering creates a moist zone on the exterior of a foundation, whereas the interior is dry; this creates differential swelling pressure on foundation elements.
source: Damage to Foundation from Expansive Soils (pdf)
Texans tend to overwater due to the unpredictability of the weather patterns. However, maintining a constant moisture level in the soil surrounding your foundation is imperative for home owners. Overwatering exerts added pressure on foundation walls which can cause them to swell upwards, thus causing the infamous, unsightly cracks to appear in walls.
Watering - Year-round watering should be planned to avoid too much moisture in the rainy season and too little in the dry season. Automatic watering systems may help, but they can require a seasonal adjustment and attention to maintenance. If the valve accidentally sticks open, major damage could result.
source: Living with Expansive Soils (pdf)
Installing Landscaping too Close to a Foundation
When considering landscaping for your house, it is important to keep plants a safe distance from the foundation, usually 5 feet or more. Landscaping planted too close to a foundation can cause the soil to expand through overwatering, deprive the plants of moisture (when the roots reach under the foundation), or in cases of trees cause foundation problems because of their roots.
How Close to the House Should You Place Foundation Shrubs?
Having shrubbery right up against your house isn't good for the house, the shrubbery, or for you! So keep the following guidelines in mind when planning a foundation planting:
Locate good-sized shrubs (6 feet tall or higher at maturity) in such a way that their mature foliage will remain at least 5 feet away from the house. You can get away with planting shrubs that stay shorter a bit closer to the house. Where you live also makes some difference. In hot, humid climates, you'll want more air circulating between the house and the foundation shrubs, to discourage rot. Adequate spacing between the plants themselves, too, is important, to reduce disease and maintenance.
source: David Beaulieu - About.com:Landscaping
Improper Installation of Swimming Pools
Swimming pools installed improperly can lead to water seepage into the soil. In Central Texas, the expansive soils will absorb this water and put increased pressure on your home's foundation. Insure that proper waterproofing has been installed when purchasing a home with a swimming pool
As swimming pools are always in direct contact with water and the hydrostatic head is very high, the waterproofing of swimming pools has to be considered very seriously from beginning and adequate steps are to be taken to ensure their water tightness.
source: Swimming Pool Protection System (pdf)
Pool shells always leak some amount of water from natural percolation through the structural gunite skin. If the pool is close enough to adjacent foundations, the entire building can be lifted differentially.
source: Damage to Foundation from Expansive Soils (pdf)
Improper drainage
Proper drainage is an essential part of any home design. Included in this are gutters which deposit the water far enough away from the foundation to prevent it from influencing the foundation. Also a proper grade in which the land around the house gradually slopes downward, away from the house and deposits runoff water on the streets.
The foundation should always be provided with adequate drainage, and the soil properly prepared to minimize changes in soil moisture and differential movement.
source: US Department of Defense: Foundations in Expansive Soils (PDF) section: 7-1
Superior Foundation Repair recommends depositing water from gutters and downspouts 10 feet (or further) from home foundations located in areas with expansive soils. Superior also recommends a grade of 3-5% sloping away from the foundation.
Interior Remodeling
When remodeling your home, it is important to understand why your home was designed the way it was in the first place. A major remodeling project which shifts the load of the house significantly, can adversely affect the original design of a foundation. Removal of supporting walls can wreak havoc. Also installing add-ons to a house situated on expansive soil can have the reverse effect intended, if not properly desinged for expansive soils. Make sure your contractor uses a design which will not be adversely affected by shrinking and swelling.
Interior finishing. One of the most costly mistakes a homeowner or careless contractor can make is to defeat the design purpose of a floating floor slab. A floating garage or basement floor slab is designed to move freely. Therefore, any furring, paneling, dry wall, or interior partitions added to a basement or garage must maintain this freedom of vertical movement. Any added walls or wall coverings should be suspended from the existing walls or ceiling, and should not be attached to the floor slab. A minimum void space of 3 in. should then be provided just above the floor slab. This void space may be covered with flexible molding, or inflexible molding attached to the floor rather than the wall. Although these recommendations provide for 3 in. of upward swell of the soil beneath the floor slab, more void space may be necessary in areas of highly swelling clay. source: Colorado Geological Survey: Mitigation and Land Use (Swelling Soil)
Should your house experience foundation problems due to improper maintenance. Contact Superior Foundation Repair immediately for a Free Foundation Repair Estimate on the extent of damage done to your home.
Read our Foundation Maintenance tips for more information on maintaining a healthy home foundation
Posted by Craig Milam on Mon, Nov 30, 2009 @ 08:39 AM

Cracks in walls allow water to seep in to sunken areas & basements
- can ruin furniture in sunken areas
- can also damage carpeting and flooring
- can cause mold to form, leading to health problems
- As a child our house outside of Houston, Texas, had a sunken living room which was built about 3 feet below ground level. Every time we had considerable rain (several times per year in Houston), our sunken living room filled with dirty water, saturating our furniture. The problems worsened year after year, until we hired a foundation repair company to come out and repair our foundation. After the repairs, water seepage was effectively stopped.
The condition of your foundation directly affects the price of your home and oftentimes affects the status of your home's eligibility for a loan from potenial home buyers.
"Foundation cracks and settlement problems are viewed as serious defect to a home. Most homeowners realize this and simply will not purchase a home unless proper repairs are made. In addition, many lending venues (FHA,VA,Conventional) simply will not lend on a home with these defects." source: www.repairfoundation.net
- The FHA may categorize your house as a "Fixer-Upper" requiring the purchaser to get a special type of loan, subsequently lowering the value of the house.
- The VA has special guidelines pertaining to foundation repair this example details guidelines for a loan term of 30 years on a manufactured home:
"To be eligible for a VA loan term of 30 years, a manufactured home must be
classified and taxed as real property
properly affixed to a permanent foundation (Section 12.10)
substantially conform with VA MPRs (Chapter 12), and
conform with applicable building code and zoning requirements for real estate."
For more information on the VA and foundations download this PDF (over 600 pages) and search for the term foundation
The longer one waits to repair a foundation, the more repair will be needed in the future
- Logically, the more a foundation shifts the larger the cracks in walls and flooring become, thus the more the costs of repairing your house increase. Stop foundation problems early to avoid future headaches.
- Typical repair costs for repairing cracks
25% of homes across the United States will experience foundation shifting, a higher percentage can be expected in Texas due to the high concentration of expansive soil
"Expansive soils are present throughout the world and are known in every US state. Every year they cause billions of dollars in damage. The American Society of Civil Engineers estimates that 1/4 of all homes in the United States have some damage caused by expansive soils. In a typical year in the United States they cause a greater financial loss to property owners than earthquakes, floods, hurricanes and tornadoes combined.
Even though expansive soils cause enormous amounts of damage most people have never heard of them. This is because their damage is done slowly and can not be attributed to a specific event. The damage done by expansive soils is then attributed to poor construction practices or a misconception that all buildings experience this type of damage as they age."
source - geology.com
Repairing your foundation and the damage associated with it can help you lower energy costs.
After reading Superior's 10 signs of Foundation Problems it is easy to see how repairing shifted windows and cracks in a structure can affect energy costs.- Percentage of energy lost from different areas of a home:
"Heat is lost to infiltration and air loss by over 3 times the amount it is lost due to ceilings. These categories generally stack up this way in terms of % heat loss in a home:
Infiltration / Air Leakage: 35%
Windows and Doors: 18%-20%
Floors and Below Grade Space: 15%-18%
Walls: 12%-14%
Ceilings: 10%"
source: About.com
- Perform an Energy Audit on your home to determine how much energy you are wasting
If you think your house is experiencing
foundation problems then contact Superior Foundation Repair today for a
free foundation repair estimate, if any are needed.
Further reading: article about how to properly
maintain a foundation
Posted by Craig Milam on Mon, Nov 16, 2009 @ 04:49 AM
According to the Austin-American Statesman, this years El Niño weather pattern could ease the drought conditions in Central Texas. What does that mean for homeowners in the Central Texas area? It means its time for a period of soil swelling.
Central Texas sits in an area of the United States which is highly affected by expansive soils. (source: geology.com)
Expansive soils contain minerals such as smectite clays that are capable of absorbing water. When they absorb water they increase in volume. The more water they absorb the more their volume increases. Expansions of ten percent or more are not uncommon. This change in volume can exert enough force on a building or other structure to cause damage.
source: http://geology.com/articles/expansive-soil.shtml
With the coming wet weather, Central Texas soils will be absorbing moisture, and subsequently expanding which can lead to increased strain on home and building foundations.
In periods of increased rainfall it is important to be cautious when watering your foundation. Ovewatering causes the soil to absorb too much water, thus expanding, and possibly leading to foundation problems. A good tip for watering your lawn/foundation is to water it enough to keep your plants alive and healthy, saturation is neither good for plants nor foundations.
For the time being, however, water restrictions are still in effect, so overwatering should not be an issue until water restrictions are lifted completely.
******************************
An Excellent video on keeping your foundation moist in drought conditions
Article on geology.com about Insurance companies and foundation repair insurance.
Technorati Tags: foundation repair, home improvement, house leveling, travis county soil, soil types, structural foundation repair, how to, austin soil, austin foundation repair
Posted by Craig Milam on Tue, Nov 10, 2009 @ 06:16 AM

Home Owners Insurance typically won't cover foundation repair
In most cases, foundation repair is not covered by Home Owners insurance. Insurance is designed to cover unexpected/sudden problems which may occur, while home Foundation Problems generally occur over a longer period of time. In certain instances, however,a policy may cover home foundation repair.
Instances where Insurance may cover house leveling costs:
- Poorly designed plumbing system causes unsuspected foundation problems, normally seen as an unexpected/sudden problem which has to do with the construction of the house rather than the soil it is sitting on.
- In cases of earthquake, if a home owner pays a premium for Earthquake insurance, and needs foundation repair due to an earthquake, repairs will usually be covered by the insurance company. (More information on home owners insurance)
In some cases of flooding, if a home owner pays a premium for flood insurance, policy may cover foundation repair to problems associated with flooding, however, home owners should check their policy and/or contact their insurance provider to clarify the extent of coverage. (FEMA's National Flood Insurance program)
Home owners should know their policy
In all cases, home owners should contact their insurance company to determine the extent of their coverage, and shop around for the best deals on insurance. Know what types of foundation repairs may or may not be covered by a home insurance policy.
Home improvement financing
In cases where home owners insurance does not cover structural foundation repair. Many home owners opt for home improvement financing to pay for foundation repair/house leveling services.
Technorati Tags: foundation repair, home improvement, house leveling, flood insurance, foundation repair insurance, structural foundation repair, home owners, repair, home owners insurance