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Our comprehensive consulting services regarding the stone and tile industry range from advising installers and enlightening end users, to investigating insurance claims and providing litigation support to attorneys, including expert witness testimony. We have experience with a broad range of processes and materials including a variety of tile, natural stone, and synthetics used in multiple residential and commercial settings such as paving, decks, patios, veneer, showers, countertops, floors, fireplaces, pools, and spas. See examples of tile and stone materials we have worked with.


Forensic Investigation & Failure Analysis

Forensic failure investigations entail the collection and analysis of evidence to help determine cause of failure in components, systems and structures, as in a swimming pool construction defect case.


Technical Consultation

NTSA expert services provide a broad range of consulting, testing and informational support services to the tile and stone industry.


Quality Control & Assurance

Quality refers to the project requirements established by the contract documents. There is not “low quality” or “high quality”; there are simply lesser or greater requirements.

National Tile also offers for owners and contractors a (third party) Quick Assessment to evaluate problems and identify solutions, with immediate/next step alternatives, quickly and at an affordable rate. Please call for details.

See Services for more details.

About Us

Greg and Gil met in 2006 while serving together on an industry technical committee and quickly came to appreciate each other’s skillset and passion for the industry. Learn more about NTSA.

Greg Andrews

Greg Andrews

Greg Andrews, a tile contractor in Southern California, has been an active tile installer since 1973. Having experienced most all aspects of installation types and techniques, Greg is a glass mosaic specialist with a primary focus on pools and water features since 1994.

While still keeping active in installations, Greg’s focus in the past decade has gradually turned toward industry involvement in the form of teaching, lecturing, training and consulting.

Greg Andrews

Gil Chotam

Gil Chotam spent several years as a tile and stone contractor before transitioning into full time consulting in 2004. Possessing a unique gift in technical and administrative skills, in addition to forensic investigation and litigation support, Gil is frequently retained by large tile and stone contractors for support in streamlining their operations.

Quality is not just a word to us — it is our passion.

Tiled Pools, Spas & Water Features

One of the least understood topics in our industry, tile in submerged conditions, is also one of the most challenging, as it fall directly between the pool and tile industries. Read more.