|California Real estate Inspection Services|
Is An Inspection?
What Does An
When Do I Request An
Can a Building “FAIL”
What If The Report
If The Report Is
Favorable, Did I Really Need An Inspection?
Why Do I Need An
Can I Inspect The
What Will The
Should I Attend The
What Is Efflorescence?
Sulfate is a
naturally occurring mineral salt compound. In California, soil
deposits are often rich in gypsum, and are laced with gypsum veins.
Gypsum is a form of calcium sulfate (CaSO4). Sulfate deposits in
soils with a marine origin are also high in sodium sulfate (NaSO4)
and magnesium sulfate (MaSO4). When the soil becomes wet from
irrigation or rainfall, the sulfates dissolve in the water and seep
into the porous concrete. Once the deterioration starts, the damage
to the concrete cannot be reversed.
typically appears in the form of hairline cracks called "etching",
or white, powdery stains referred to as "efflorescence." The best
place to look first is on the garage floor or driveway, or along the
exterior foundation. However, not all white powder is sulfate. As
the sulfate attack worsens, other parts of the home's foundation
will show signs of efflorescence and etching. It can also appear on
patios, driveways, swimming pools and other so-called "hardscape."
If you are suspicious and want to know for sure, a geotechnical firm
can take a sample from your home and analyze it.
How many homes are affected by sulfate damage?
of thousands of homes, apartments and condominiums along the coastal
and inland areas of California are built on sulfate laden soils that
can, under certain conditions, destroy the concrete foundations. One
expert said sulfate cases could cost the Southern California
homebuilding industry - or more precisely, their insurance
companies - as much as the Northridge earthquake.
Is it strictly a California
sulfate levels seem to be concentrated in areas once covered by
seawater, which created large deposits of gypsum. Gypsum is a common
source of sulfate. Many parts of California were once covered by the
ocean; some of these areas have high levels, some have low levels,
and some are sulfate free. It depends on the type of soil and other
factors. Soils rich in sulfates are found throughout the United
States, and throughout the world.
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the Uniform Building Code has required that a special Type V cement
be used in high-sulfate soils, and that a lower water-to-cement
ratio be used to maintain a proper level of density in the concrete
after curing. Dense concrete stops groundwater from seeping in;
it's the water that carries the sulfates. According to the UBC, the
ratio of water-to-cement in high-sulfate soil conditions should be
no more than 0.45. However, in many cases that have been
investigated, the ratio is more like 0.65 to 0.70, or 50% in excess
of maximum. The result is concrete with an interconnected pore
structure, and therefore not dense. The denser the concrete, the
less likely the water will seep in.
many builders have complied with UBC sulfate requirements. However,
concrete used in construction of potentially tens of thousands of
California homes built on high-sulfate soils since the mid-1980s
does not meet Uniform Building Code standards, creating a defect
that can result in the concrete's decomposition. One reason is that
contractors and suppliers of concrete ignored the UBC requirements.
Compounding the problem, those contractors who poured concrete at
building sites frequently mixed in additional water to make
installation quicker or easier.
As the sulfate
infiltrates concrete, it combines with the C-S-H, or concrete paste,
and begins destroying the paste that holds the concrete together. As
sulfate dries, new compounds are formed, often called ettringite.
These new crystals occupy empty space, and as they continue to form,
they cause the paste to crack, further damaging the concrete. The
concrete weakens and the paste continues to separate and crack.
Consequently, the concrete becomes increasingly permeable, allowing
in more and more water filled with sulfates. Over time the process
accelerates dramatically. The excess water content and porosity
also begin to rust away the anchor bolts that tie the home's
structure to the foundation.
the concrete foundation disintegrates and turns to rubble. This
condition, coupled with the rusting structural ties and anchor
bolts, puts a home and its occupants at greater risk from
earthquakes, high winds and other destructive forces of nature.
According to the National Association of Home Builders, the useful
life of concrete should be about 150 years; however, left
unattended, sulfate attack can cut that lifespan to 15 years or less
CREIA has established a high Standards of Practice for the inspection profession that is used throughout the state to ensure the buyer who retains a CREIA member of a complete and detailed inspection and report.
All members must abide by these standards and Code of Ethics. CREIA offers its members and candidates continuing education in the latest building technology, training, and materials to ensure the most professional inspection for the consumer. CREIA acts as a public information service to real estate buyers and provides technical support and training to realty agents, state agencies and other related professions.
Many CREIA members have engineering, architectural, or technical backgrounds. Most members have had experience in various construction fields and are or have been building contractors.
In addition to performing building inspections, many CREIA inspectors help with analysis and solutions to specific problems, such as foundations, energy conservation, and roofing problems. CREIA inspectors are also frequently called upon to review restoration and home improvement plans as well as maintenance specifications, contracts and progress inspections for new construction to help ensure proper completion of contracted work.
If you find that you are involved in a
dispute regarding construction work performed on your building, a
CREIA member can provide expert advice. Also, many CREIA members
inspect commercial and investment properties, multiple unit
dwellings, condominiums, townhouses, mobile homes and perform
reserve studies as well.
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