Cracked pool coping grout

Not every crack is a defect, as cracking in pool coping and tile grout is completely normal.

Tight cracks

Grout is strictly a cosmetic filler between tiles and coping stones.  Grout does not serve any structural purpose, other than to fill the voids between materials.  

Hairline cracks in the grout between swimming pool copings is totally acceptable.  As the grout cures and loses moisture, it shrinks slightly, possibly even pulling away slightly.  Combined with the natural expansion and contraction of the coping material, these cracks will develop - GUARANTEED.

A hairline crack along one side of a joint or through it's length is to be expected.  As long as the grout does not begin to crumble, dislodge or decay, hairline cracks are totally acceptable.

Many new pool owners are alarmed when they observe small hairline cracks in the grout of the copings or tiles. The assertion that grout does not crack inside their residence, does not apply to outdoor materials.  Outdoor materials are subject to daily 30-50ºF temperature swings, while indoor materials are in a shaded and climate controlled environment.

Decay

Of course, grout that is crumbling or dissolving is defective and should be removed and replaced.  

Exposure to extreme temperature differentials may cause grout to spall - that is, a surface flaking.  This is usually an indication of some compressive forces at play.  It may be due to thermal expansion or from differential movement.  After an initial replacement, the defect reoccurs, then that joint should be replaced with a flexible construction sealant.

Not every crack is a defect.
 
Paolo Benedetti, SWD, Principal 
Aquatic Technology Pool and Spa 
www.AquaticTechnology.com 
International Swimming Pool Consulting and Design, Aquatic Consulting, Watershape Consultants, Expert Witness, Hydraulic Design, Landscape Architecture, Construction Management 
Office: 408-776-8220 
Email: info@aquatictechnology.com 

Major Markets Serviced: San Francisco, Palo Alto, Atherton, Hollywood Hills, Beverly Hills, Malibu, Los Angeles, San Diego, San Clemente, Pacific Palisades, Escondido, Scottsdale, Seattle, Phoenix, Tempe, Portland, Aspen, Vail, Park City, Chicago, Dallas, Houston, Austin, New Orleans, Madison, Detroit, East Hamptons, South Hamptons, Cape May, Ft. Lauderdale, Orlando, Raleigh, Chapel Hill, Cherry Hill, Toms River, Salt lake City, Boise, Denver, Santa Barbaara, Carmel, Carmel Valley, Monterey, Pebble Beach, Oceanside, Big Sur, Napa, Sonoma, Sausalito, Danville, Belvedere, Montecito, Palm Springs, Midland, Manhattan, Greenwich Village, Osaka, Paris, Madrid, Barcelona, London, Seoul, Sydney, New York, Tokyo, Cairo, Istanbul, Athens, Rome, Lisbon, Bonn.

Glass tile failure - cracked and shattered

Thermal shock and expansion causes shattered, cracked and spalled glass tiles.


Many of the glass tile manufacturers have yet to produce products that meet the ANSI A137.2 performance standards.  

Why?  It is less expensive to simply replace any cracked tiles with new tiles, than it is to manufacture and perform testing to ensure compliance.  The manufacturers know that they can also deflect many failure warranty claims by blaming the installation process.  
They will quickly point out the installers failure to install expansion joints as the cause of any failure.  And the manufacturers will continue to refuse to produce products that are compliant with the standards they wrote.

Boyce & Bean glass tiles (manufactured by Crossville)

The ANSI standards state that any glass tiles that do not meet the thermal shock resistance standard, cannot be specified for use outdoors.  In fact, they are relegated to use in dry indoor wall applications only (kitchen back splashes and decorative walls).

The manufacturers want to have their cake and eat it to.... they refuse to create compliant products, but they will blame an installer for failing to comply with the installation standards.

Shouldn't glass tile manufacturers comply with their own industry standards?

Or be forced to stop marketing non-compliant glass tile as being suitable for outdoor and swimming pool applications?

 

Paolo Benedetti, SWD, Principal Aquatic Technology Pool and Spa www.AquaticTechnology.com International Swimming Pool Consulting and Design, Aquatic Consulting, Watershape Consultants, Expert Witness, Hydraulic Design, Landscape Architecture, Construction Management Office: 408-776-8220 Email: info@aquatictechnology.com Major Markets Serviced: San Francisco, Palo Alto, Atherton, Hollywood Hills, Beverly Hills, Malibu, Los Angeles, San Diego, San Clemente, Pacific Palisades, Escondido, Scottsdale, Seattle, Phoenix, Tempe, Portland, Aspen, Vail, Park City, Chicago, Dallas, Houston, Austin, New Orleans, Madison, Detroit, East Hamptons, South Hamptons, Cape May, Ft. Lauderdale, Orlando, Raleigh, Chapel Hill, Cherry Hill, Toms River, Salt lake City, Boise, Denver, Santa Barbaara, Carmel, Carmel Valley, Monterey, Pebble Beach, Oceanside, Big Sur, Napa, Sonoma, Sausalito, Danville, Belvedere, Montecito, Palm Springs, Midland, Manhattan, Greenwich Village, Osaka, Paris, Madrid, Barcelona, London, Seoul, Sydney, New York, Tokyo, Cairo, Istanbul, Athens, Rome, Lisbon, Bonn.