2024-25_NTCA_Reference_Manual_dig_dwnld

Cracked Natural Stone Tiles

Problem

Prevention

Cure

Insufficient or uneven bond coat coverage.

Seepage190“ProperBeddingProcedures.” Flat back-troweling natural stone tiles.

Replace the broken tiles and correct the cause.

Improper bonding material.

Use setting materials that comply with ANSI specifications and methods detailed in the TCNA Handbook . Proper placement of control or expansion joints ( TCNA Handbook method EJ171), and proper substrate preparation for the installation of natural stone tile, including the use of 2 structural layers for wood frame construction. Use thicker and/or more durable class of tiles if subjected to unusual impact or heavy loads.

Replace the broken tiles and correct the cause.

Movement in substrate.

Replace the broken tiles and correct the cause, where possible.

Impact resistance requirement too great for materials selected.

Replace the broken tiles and correct the cause.

Insufficient bond caused by contaminated back surfaces. Natural stone and agglomer ate tiles are subject to fabrication residue.

Adequately clean back of stone and substrate surface.

Replace the broken tiles and correct the cause.

Contaminated substrate.

Prepare substrate to industry specifications (scarify if necessary).

Replace the broken tiles and correct the cause.

Applied over slab cracks.

Treat slab cracks with isolation membrane before installing tile.

Remove affected tiles plus additional tile on each side of crack. Install isolation membrane. Remove damaged tile and install expansion and/or control joints in stone directly over substrate joints.

Omission of expansion or control joints.

See TCNA Handbook method EJ171 for treatment of expansion or control joints.

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NTCA Reference Manual | 2024 / 2025

Chapter 6 | Natural Stone Installations