​Chinese Drywall INSPECTION with XRF 

How we determine if your property has Chinese Drywall

 Benefits of the report for confirmed tainted homes include:

  • Documentation for mortgage forbearances
  • Documentation for insurance claim submission
  • Documentation for attorney's use
  • Documentation for property appraisers office*
  • Documentation for income tax deductions**

Benefits of the report for confirmed clean homes include:

  • Documentation to lenders for re-financing, equity lines or home additions
  • Documentation for rental and sales listings
  • Documentation for tenant retention
  • Peace of mind

Chinese Drywall Screening, LLC (CDS) will conduct a detailed visual inspection of the various elements within the home that typically react to the presence of reactive drywall.  Some of the known affects are pitting and blackening copper, tarnishing silver, corroding and spotting chrome and brass, and delaminating mirrors. This inspection will provide a general summary of the areas that have corrosive drywall.  Based on the experience, knowledge and ability to recognize these affects, CDS will complete a thorough inspection of the various elements of the home containing these materials.  These elements include, but are not limited to: Air conditioning components; Coaxial cabling; Gas lines (if applicable); Refrigerator components; Water lines; Mirrors; Electrical wiring; Plumbing fixtures and drains.

Some of the above elements will be photographed during the inspection and will be included in the report.  Items that may be affected by reactive drywall but were not inspected by CDS include, but are not limited to: Large appliances; Smoke detectors; Small appliances; Doorbells; Televisions; Security systems; Audio/video equipment; Control wiring; Personal possessions; Thermostats.

We also utilize X-ray Fluorescence (XRF) to test Strontium levels in the drywall.  XRF analyzers are handheld instruments used predominantly to evaluate the presence of metal constituents in building materials or other products.  XRF works by exposing a material to high energy x-rays and measuring those x-rays and comparing them to the known and unique pattern of x-rays produced by each element.  For help in identifying corrosive drywall, XRF is used to determine levels of strontium (Sr) present within the gypsum of the drywall throughout the property. 

Strontium is a light metal that is a common, naturally occurring element found within the earth.  Certain geographical regions have higher concentrations than others that can translate to the origin of the raw materials.  Strontium levels above 1850 ppm have been associated with drywall of Chinese origin.  However, high levels of strontium do exist in drywall from other origins and testing must be used in conjunction with other means to produce proper conclusions. 

Sulfur Corrosion Testing of Drywall Samples
Our internally developed method of sulfur corrosion testing specific samples of drywall is to analyze copper and/or silver coupons for deposited sulfur utilizing x-ray fluorescence.  The sulfur is a byproduct of the corrosion of the metals from emitted sulfide gases.  Problematic or corrosive drywall emits sulfide gases that react with copper and silver to form copper sulfide and silver sulfide respectively on the surface of test coupons.  This process can be accelerated by elevating the temperature.

X-ray fluorescence (XRF) is utilized to quantify the sulfur deposits on the coupons in ug/cm2 (micrograms per square centimeter).  Readings can then be interpreted to determine to whether the drywall tested is corrosive and at what proportionate levels.  A non-detect (ND) reading upon analyzing the test coupons indicates there are no detectable sulfur deposits on the surface of the coupons.   This in turn leads to the conclusion that the drywall is non-corrosive at any significant or detectable levels during the course of the testing period.   Positive readings for sulfur are compared against various controls and known samples in order to make proper determinations as to the conditions of the samples being tested.  Samples with low levels of off gassing may need multiple rounds of testing to verify that the gypsum is the root source of the corrosive gases and the sulfur deposition is not a result from de-absorbed environmental sources.


  • Overview of your situation
  • Complete summary and findings of the items/areas inspected
  • Photograph documentation of the inspection
  • List of potential follow up action items
  • Resources and reference materials.

*Former Govenor Crist signed a bill to value homes at $0 (not including land) for property tax purposes.  Be sure to send them your report asap before state deadlines to save on property taxes.

**See resource page for an article on deducting losses against federal income taxes.