Thursday, January 27, 2011

What is a Footing?

The footing (a.k.a. "spread footing") is the bottom part of the foundation and is usually made of concrete and reinforced with steel (rebar). The footing forms the base of the foundation and spreads the vertical loads from building.

Footing requirements are usually covered by municipal building codes and sized with respect to the bearing capacity of the soil and the building's weight. While we typically don't need to worry about this in north Texas and southern Oklahoma, other areas may be subject to seasonal frost. In these areas, the bottom of the footing must be below the frost line to prevent damage to the footing because of frost heave.

Types of Footings

The most common types of footings are:

Spot Footings

A spot or pad footing is used to support a single point of contact, such as under a pier or post. Spot footings are usually a 2' by 2' square pad, 10" to 12" thick, and made with reinforced concrete.

Continuous Spread Footing

A continuous spread footing is mainly used to provide a stable base around the perimeter of a building. Spread footings are often augmented with interior spot footings. The spread footing supports the weight of the exterior or foundation walls. The thickness of the footing provides the necessary strength for that support. The wide width of the footing base provides a large area with which to transfer the weight from the walls to the ground. This is key to preventing settlement.

Grade Beam Footing
A grade beam footing is a continuous reinforced-concrete member used to support loads with minimal bending. Grade beams are capable of spanning across non-load bearing areas, and are commonly supported by soil or pilings.Grade beam footings differ from continuous spread footings in how they distribute loads. The depth of a grade beam footing is designed to distribute loads to bearing points, while the width of a continuous spread footing is designed to transfer loads to the ground.

Get more information by visiting www.AceFoundation.com.

Thursday, January 20, 2011

What Cold Weather Means for Your Foundation

When we think about building foundation problems in north Texas, we tend to think about Summer. Perhaps it's our nearly perennial droughts or maybe it's because we're outside in the yard more and we notice the soil more. In any case, you're among good company if thoughts of foundation problems are few and far between this time of year.

But, for all the Summer conditions that lead to foundation problems, there's a Winter condition, too. First off, where soil contracts due to lack of moisture during the Summer, it can expand during the Winter as ice storms, rains, and cold temperatures keep more water in the soil. Expanding soil can push a foundation upward; this is caused heave.

And, while we don't have the brutally cold winters like Chicago or Minnesota, it does indeed get cold in north Texas and southern Oklahoma. Frost damage can occur to foundations with unheated slabs on grade. Frost heave is caused when ice forms within the soil, causing overall volume of soil to increase. When the volume of soil increases, it can heave the foundation.

What can you do to prevent problems like excess moisture and frost heave? Try the following:

  • Keep an eye out for the usual signs of foundation damage: cracks in the sheet rock, newly wrinkled wallpaper, stuck windows and doors, popped floor tiles, cracks in the fireplace, etc. Call a foundation repair professional if you see one or more of these problems and get an expert opinion right away.
  • The next time it rains, pull on a coat and some waterproof shoes or boots and take a walk around the exterior of your home. This is your chance to look for puddles against the foundation. You do not want water against the foundation! Wherever you find water pooling against the house, mark it with a stake or other marker. Hire someone to fix the drainage at these points. (Or, you can do it yourself.)
  • Check outdoor spigots and your sprinkler system for cracks and freezes. These items are your first line of defense come Spring and Summer, but now's the time that these items freeze and break.

These simple winter foundation maintenance tips can make a big difference between comfort, costs, and your family's piece of mind — so be sure to take a few minutes now so you won't have big problems later.

Get more information by visiting www.AceFoundation.com.

Saturday, January 15, 2011

Foundation Repair Glossary, The Entire List

As promised, here's our complete Foundation Repair Glossary in one great big list. Remember, if you have a question about any of these terms, be sure to ask us!

Active Zone
This is the depth of soil instability or movement, usually caused by changes in moisture. Sometimes, the active zone is referred to as the Seasonal Zone.
Bell Bottom Pier
A concrete pier that has a bell-shaped bearing surface.
Builder Piers
When the builder pours the grade beam for a pier and beam foundation, the builder piers are poured first. Builder piers are poured with a spacing of four to eight feet apart and to an average depth of three to four feet. These piers hold the grade beam in place. Sometimes builder piers fail, due to their low level of placement.
Clay
Crawl Space
The space between the bottom of the structure and the ground. This is common or necessary with pier and beam foundations. A properly engineered crawlspace allows enough room to vent moisture and allow for work on plumbing, electrical, and other utilities under the building.
Composed primarily of fine-grained minerals, clay is a naturally occurring component of soil. Clay expands greatly when mixed with water but then significantly contracts when water is withdrawn. Soil expansion and contraction is one of the leading causes of foundation failure.
Deviation
Deviation is the amount by which the structure is not level. That is, the structure has deviated from its specifications and true level. Naturally, a home with a great deal of deviation requires more work (piers) to bring it back to level.
Differential Settlement
The difference in movement vertically between different parts of the foundation; Non-trivial differential settlement can cause foundation failure.
Drilled Pier
Drilled piers involve drilling a hole at an angle to a predetermined depth under the slab, then using rebar to build a form in, then filling in the hole with concrete. If the conditions that caused the foundation to fail in the first place aren't remedied, then it's highly likely that the drilled pier will fail in time.
Elevation
Elevation is the series of measurements used to determine the difference in height between a central point and other points.
Engineers Report
An engineering report is done after a foundation has been repaired or before a structure is purchased. The report determines whether or not the foundation can perform its intended function and whether or not any remedial foundation repairs are necessary. In Texas, the report is a level "B" investigation (as described by the Texas Board of Professional Engineers and the American Society of Civil Engineers). The report will be sealed and signed by a Professional Engineer. The engineering report usually includes: Foundation Analysis, Interior Observations, Exterior Observations, Conclusions, Recommendations, and Photo File.
Epoxy Injection
Epoxy injection is used for concrete in manner similar to how welding is used for steel. That is, epoxy is used to fill cracks in concrete; often times, though, the cracks remain as weak point in the foundation.
Footing
Footings, typically constructed of steel-reinforced concrete, is the bottom part of the foundation. The footing spreads the vertical loads from the building sitting on top of the foundation. With slab foundations, the footing is usually two feet and runs the entire perimeter of the slab.
Foundation
A home foundation is that part of the structure that is in direct contact with the ground. The foundation transmits the weight of the entire home and itself to the supporting soil.
French Drain
A drain that is used to collect water that migrates under ground. It is not used to collect large amounts of water from a heavy rain fall. French Drains are usually dug down 36-48 inches. Then 1 1/4” river rock is placed at the bottom of the trench and a 4” corrugated pipe is placed over this rock. Once in place, the trench is filled with river rock to approximately 4-6” below grade. The last 4-6” are then topped with soil and/or sod.
Galvanizing
Galvanized metal is made via an electromechanical process by which steel (or iron, or other metal) is coated with a non-rusting metal, such as zinc. The zinc simply isn't painted on the steel but rather is deposited and bonded to the steel via electrode position. The long and short of it all is that the steel is protected by the zinc and not subject to rust.
Grade
The level of ground surface. The grade can also refer to the rise or fall of the ground over a given distance.
Grade Beam
The grade beam is the concrete support that goes around the perimeter of a Pier & Beam foundation. This is what home and bricks are supported by along the perimeters. The concrete grade beam is, on average, poured 18-20 inches below soil grade and is reinforced with rebar laid inside the concrete for additional support.
Helical Pier
A helical pier is a steel shaft to which circular steel plates have been welded at an angle (thing of a large screw). Helical piers offer more resistance and support than traditional steel piers, which do not have steel plates.
Initial Site Inspection
An initial site inspection determines the most likely cause of damage and if it's caused by the foundation. The initial site inspection requires the inspector to gather lots of information including but not limited to structural and architectural drawings, grading plans, and plat of survey.
Jacking
A method by which a static driving force is performed on a pile by jacks.
Live Load
This is the additional weight added to a structure by people, furniture, snow, ice, water, etc.
Mudjacking
A foundation repair process used by some foundation repair businesses where water and soil cement or soil-lime-cement grout is pumped beneath the slab to lift the slab to the desired position. We recommend mudjacking only for flat concrete surfaces such as garage floors, driveways, pool and patio decks.
Pier
A support under a structure's foundation. Piers can be made of wood, steel, concrete and sunk into the ground or resting atop ground (for smaller structures).
Pier and Beam
A foundation construction method where the structure is supported several feet off the ground by pillars and posts or pilings (a.k.a. the piers).
Pier Depth
The depth to which piers are sunk. Piers must reach a depth that provides adequate support. This means to bedrock or to a particular soil density. The deeper the piers must be sunk, the more expensive the foundation repair job will be.
Post-Tensioning Cable Foundations
A foundation construction technique where high-strength steel strands or cables, typically referred to as tendons, create a grid of steel cables that actively support the slab.
Pressed Pier
A pressed pier is made up of individual pilings that are pre-pressed and pre-formed. These pilings, in turn, are pressed into the ground using a hydraulic press. The individual pilings are locked to each other with steel shims or a piece of cable.
Rebar
Rebar, also known as reinforcing steel or reinforcement steel, is a common steel bar used to reinforced concrete.
Refusal
The condition reached when a pier can't be driven any farther, like when the pier reaches an impenetrable bottom such as rock). The term refusal may be used to indicate the specified minimum penetration per blow. Driving piers beyond refusal can damage the piers.
Retaining Wall
A retaining wall supports eroding soil in areas where the ground is likely to shift. Retaining walls can also provide additional support to foundations built up with fill dirt.
Root Barrier
Root barriers are physical barriers that redirect tree root growth downward, thus eliminating surface rooting that can damage foundations, sidewalks, driveways, and other hardscapes
Settlement
Settlement occurs when a part of the foundation drops below the original as-built grade.
Slab
A concrete foundation supported entirely by the surface soil. Slab foundations are popular in most new residential construction in areas with high-clay soils, such as that found in north Texas and southern Oklahoma.
Soaker Hose
A gardening hose capped on one end and containing hundreds of tiny perforations. A soaker hose set next to a structure's foundation can help maintain a consistent moisture level within the soil and help prevent foundation movement and, consequently, foundation failure.
Soil
The collection of loose material, including air, water, and solid particles, comprising the Earth's crust. It's comprised of a mixture of mineral and organic materials in solid, gaseous and aqueous states. When discussing foundation construction, maintenance, and repair, we are most concerned with the moisture content of the soil.
Soil Stability
Soil material (clay, sand, etc.) and drainage play a big part in how much water the soil can contain and how often that soil is asked to contain that water. If the soil's moisture content changes often and/or a great deal, your foundation will move as the soil contracts and expands with moisture.
Soil Stabilization
This is the process by which a contractor improves the natural properties of soil to make it a better base for construction. Soil stabilization reduces or eliminates erosion, controls the movement of water through a given parcel of soil, and seeks to moderate the soil's moisture content.
Structural Engineer
An independent registered professional engineer that specializes in civil or structural engineering.
Subsidence
The sinking of all or part of a structure's foundation.
Sump Pump
A pump which removes water from a sump pit. (The sump pits simply a hole into which water is drained; the sump pit is commonly found in the basement.)
Upheaval
The lifting of all or part of a structure's foundation.
Void Filling
A low pressure injection of grout slurry that fills the space between a foundation and the soil beneath the foundation.
Waffle Slab Foundation
Waffle slab foundations are formed when beams are poured throughout the interior until the pattern resembles a waffle.>

Get more information by visiting www.AceFoundation.com.

Thursday, January 13, 2011

Foundation Repair Glossary, Part 4

Here's the last post in our four-part series, Foundation Repair Glossary. This post catches us up on terms that didn't make it into the prior three posts. Don't worry — we'll post the entire glossary from start to finish so you have the whole thing at your fingertips!

Bell Bottom Pier
A concrete pier that has a bell-shaped bearing surface.
Crawl Space
The space between the bottom of the structure and the ground. This is common or necessary with pier and beam foundations. A properly engineered crawlspace allows enough room to vent moisture and allow for work on plumbing, electrical, and other utilities under the building.
Deviation
Deviation is the amount by which the structure is not level. That is, the structure has deviated from its specifications and true level. Naturally, a home with a great deal of deviation requires more work (piers) to bring it back to level.
Differential Settlement
The difference in movement vertically between different parts of the foundation; Non-trivial differential settlement can cause foundation failure.
Drilled Piers
A pier formed by drill a hole at an angle to a predetermined depth, forming rebar within the hole, and then filling the hole with concrete (mixed with a curing agent). A drilled pier can be expected to fail if the conditions which caused the foundation to fail in the first place are not corrected.
Epoxy Injection
Epoxy injection is used for concrete in manner similar to how welding is used for steel. That is, epoxy is used to fill cracks in concrete; often times, though, the cracks remain as weak point in the foundation.
Galvanizing
Galvanized metal is made via an electromechanical process by which steel (or iron, or other metal) is coated with a non-rusting metal, such as zinc. The zinc simply isn't painted on the steel but rather is deposited and bonded to the steel via electrode position. The long and short of it all is that the steel is protected by the zinc and not subject to rust.
Helical Pier
A helical pier is a steel shaft to which circular steel plates have been welded at an angle (thing of a large screw). Helical piers offer more resistance and support than traditional steel piers, which do not have steel plates.
Initial Site Inspection
An initial site inspection determines the most likely cause of damage and if it's caused by the foundation. The initial site inspection requires the inspector to gather lots of information including but not limited to structural and architectural drawings, grading plans, and plat of survey.
Root Barrier
Root barriers are physical barriers that redirect tree root growth downward, thus eliminating surface rooting that can damage foundations, sidewalks, driveways, and other hardscapes
Pier and Beam
A foundation construction method where the structure is supported several feet off the ground by pillars and posts or pilings (a.k.a. the piers).
Pier Depth
The depth to which piers are sunk. Piers must reach a depth that provides adequate support. This means to bedrock or to a particular soil density. The deeper the piers must be sunk, the more expensive the foundation repair job will be.
Post-Tensioning Cable Foundations
A foundation construction technique where high-strength steel strands or cables, typically referred to as tendons, create a grid of steel cables that actively support the slab.
Pressed Pier
A pressed pier is made up of individual pilings that are pre-pressed and pre-formed. These pilings, in turn, are pressed into the ground using a hydraulic press. The individual pilings are locked to each other with steel shims or a piece of cable.
Rebar
Rebar, also known as reinforcing steel or reinforcement steel, is a common steel bar used to reinforced concrete.
Retaining Wall
A retaining wall supports eroding soil in areas where the ground is likely to shift. Retaining walls can also provide additional support to foundations built up with fill dirt.
Soaker Hose
A gardening hose capped on one end and containing hundreds of tiny perforations. A soaker hose set next to a structure's foundation can help maintain a consistent moisture level within the soil and help prevent foundation movement and, consequently, foundation failure.
Soil Stability
Soil material (clay, sand, etc.) and drainage play a big part in how much water the soil can contain and how often that soil is asked to contain that water. If the soil's moisture content changes often and/or a great deal, your foundation will move as the soil contracts and expands with moisture.
Structural Engineer
An independent registered professional engineer that specializes in civil or structural engineering.
Waffle Slab Foundation
Waffle slab foundations are formed when beams are poured throughout the interior until the pattern resembles a waffle.>

Get more information by visiting www.AceFoundation.com.

Tuesday, January 11, 2011

Foundation Repair Glossary, Part 3

If you've missed our Foundation Repair Glossary Part 1 and Part 2, then be sure to catch up now.

Slab
A concrete foundation supported entirely by the surface soil. Slab foundations are popular in most new residential construction in areas with high-clay soils, such as that found in north Texas and southern Oklahoma.
Soil
The collection of loose material, including air, water, and solid particles, comprising the Earth's crust. It's comprised of a mixture of mineral and organic materials in solid, gaseous and aqueous states. When discussing foundation construction, maintenance, and repair, we are most concerned with the moisture content of the soil.
Soil Stabilization
This is the process by which a contractor improves the natural properties of soil to make it a better base for construction. Soil stabilization reduces or eliminates erosion, controls the movement of water through a given parcel of soil, and seeks to moderate the soil's moisture content.
Subsidence
The sinking of all or part of a structure's foundation.
Sump Pump
A pump which removes water from a sump pit. (The sump pits simply a hole into which water is drained; the sump pit is commonly found in the basement.)
Upheaval
The lifting of all or part of a structure's foundation.
Void Filling
A low pressure injection of grout slurry that fills the space between a foundation and the soil beneath the foundation.

Do you have questions about our Glossary of Foundation Repair Terms? If so, then ask us and we'll get you the answer. Be sure to visit our website to learn more about foundation construction, maintenance, and repair.

Thursday, January 6, 2011

Foundation Repair Glossary, Part 2

This is the second part in our glossary of foundation repair terms. Be sure to check out Part 1.

Grade
The level of ground surface. The grade can also refer to the rise or fall of the ground over a given distance.
Jacking
A method by which a static driving force is performed on a pile by jacks.
Live Load
This is the additional weight added to a structure by people, furniture, snow, ice, water, etc.
Mudjacking
A foundation repair process used by some foundation repair businesses where water and soil cement or soil-lime-cement grout is pumped beneath the slab to lift the slab to the desired position. We recommend mudjacking only for flat concrete surfaces such as garage floors, driveways, pool and patio decks.
Pier
A support under a structure's foundation. Piers can be made of wood, steel, concrete and sunk into the ground or resting atop ground (for smaller structures).
Refusal
The condition reached when a pier can't be driven any farther, like when the pier reaches an impenetrable bottom such as rock). The term refusal may be used to indicate the specified minimum penetration per blow. Driving piers beyond refusal can damage the piers.
Settlement
Settlement occurs when a part of the foundation drops below the original as-built grade.

Get more information by visiting www.AceFoundation.com.

Tuesday, January 4, 2011

Foundation Repair Glossary, Part 1

We'd thought we'd do something a little different over the next few posts and present a glossary of terms commonly used when discussing building foundation construction and repair. Let us know what you think!

Active Zone
This is the depth of soil instability or movement, usually caused by changes in moisture. Sometimes, the active zone is referred to as the Seasonal Zone.
Builder Piers
When the builder pours the grade beam for a pier and beam foundation, the builder piers are poured first. Builder piers are poured with a spacing of four to eight feet apart and to an average depth of three to four feet. These piers hold the grade beam in place. Sometimes builder piers fail, due to their low level of placement.
Clay
Composed primarily of fine-grained minerals, clay is a naturally occurring component of soil. Clay expands greatly when mixed with water but then significantly contracts when water is withdrawn. Soil expansion and contraction is one of the leading causes of foundation failure.
Drilled Pier
Drilled piers involve drilling a hole at an angle to a predetermined depth under the slab, then using rebar to build a form in, then filling in the hole with concrete. If the conditions that caused the foundation to fail in the first place aren't remedied, then it's highly likely that the drilled pier will fail in time.
Elevation
Elevation is the series of measurements used to determine the difference in height between a central point and other points.
Engineers Report
An engineering report is done after a foundation has been repaired or before a structure is purchased. The report determines whether or not the foundation can perform its intended function and whether or not any remedial foundation repairs are necessary. In Texas, the report is a level "B" investigation (as described by the Texas Board of Professional Engineers and the American Society of Civil Engineers). The report will be sealed and signed by a Professional Engineer. The engineering report usually includes: Foundation Analysis, Interior Observations, Exterior Observations, Conclusions, Recommendations, and Photo File.
Footing
Footings, typically constructed of steel-reinforced concrete, is the bottom part of the foundation. The footing spreads the vertical loads from the building sitting on top of the foundation. With slab foundations, the footing is usually two feet and runs the entire perimeter of the slab.
Foundation
A home foundation is that part of the structure that is in direct contact with the ground. The foundation transmits the weight of the entire home and itself to the supporting soil.
French Drain
A drain that is used to collect water that migrates under ground. It is not used to collect large amounts of water from a heavy rain fall. French Drains are usually dug down 36-48 inches. Then 1 1/4” river rock is placed at the bottom of the trench and a 4” corrugated pipe is placed over this rock. Once in place, the trench is filled with river rock to approximately 4-6” below grade. The last 4-6” are then topped with soil and/or sod.
Grade Beam
The grade beam is the concrete support that goes around the perimeter of a Pier & Beam foundation. This is what home and bricks are supported by along the perimeters. The concrete grade beam is, on average, poured 18-20 inches below soil grade and is reinforced with rebar laid inside the concrete for additional support.

We'll keep these rolling over the next few posts. As always, if you have a question, feel free to ask us anything about foundation construction and repair!

Get more information by visiting www.AceFoundation.com.