In a recent NTCA Webinar sponsored by LATICRETE, two seasoned experts – Joe Rizzo, Director of Sales for Concrete and Substrate Preparation, and Elvis Torres, Product Manager at LATICRETE International – shared practical insights into one of the most overlooked but critical aspects of successful tile installation: substrate preparation.
Rizzo opened with a reality check that substrate prep may not be glamorous, but it’s essential. He reminded attendees that concrete is often not flat enough to meet the strict standards required for large-format tile (LFT) and gauged porcelain panels. The American National Standards Institute (ANSI) demands far more precision for tile than typical concrete applications deliver. For example, LFT requires a substrate no more than 1/8″ out of plane in 10′, which is half the deviation allowed for general concrete. And typically, this is not specified by an architect or an industry association. It is specified by a structural engineer because the purpose of concrete in a building primarily is to be the structural element that does the heavy lifting, literally. The concerns of flatness for a floor are secondary and often something that need to be reconciled.
No margin for error
Torres and Rizzo emphasized that the size of tiles and the narrowing grout joints in modern design leave no margin for error. Imperfections in the substrate will not only show, but they will compromise the longevity and appearance of the installation.
To ensure success, the presenters outlined the following steps for surface preparation:
- Determine the flatness or level required for the application.
- Test the cohesion of the concrete slab. Determine the allowable moisture – mitigate if necessary.
- Prepare the substrate.
- Measure and mark elevations.
- Mix/pump/pour and ensure you understand the tools and techniques, from pour stops and gauge rakes to lightweight self-leveling underlayments and advanced pumping systems.
The duo also addressed how tile contractors can expand their services by taking on substrate prep work themselves or subcontracting to qualified partners. This not only increases revenue potential but also gives greater control over installation quality.
One key takeaway: whether you’re prepping for natural stone or porcelain slabs, investing the time and materials to ensure a flat, dry substrate sets the stage for everything else to go right. You save time, you get better results, and ultimately, a much happier client.
To watch the full webinar and see video demonstrations, visit NTCA’s YouTube Channel and search for “Preparing the Substrate: Flat, Dry, Easy” or watch it here:
Elena Grant
Elena Grant is the Assistant Executive Director of Marketing, Communications and Public Relations for the National Tile Contractors Association and Publisher of its publication TileLetter. Grant has over 20 years of experience leading marketing initiatives, programs, and operational enhancement strategies. As Publisher of TileLetter, she oversees all print and digital communications for the publication.
