Sunday, April 27, 2014

Glass Tile Swimming Pool - Details, Details

Glass tile installations are all about the details.  It takes a clever and astute swimming pool designer to pull it off flawlessly.

Rosetta cut tiles around a pair of spa jets, while time consuming, it was a detail the client was willing to pay for.  The results were worth it.


individually cut trapezoid glass tiles - a beautiful detail
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individually cut trapezoid glass tiles on a single spa jet
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Another detail of concern, were rounded and polished edges.  A perfectly smooth surface, guaranteeing snag free swimsuits.

polished and smoothed glass mosaic tiles on a step
(click on the image to enlarge it)

Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. Visit his website at: www.aquatictechnology.com. All Contents © Aquatic Technology Pool & Spa, 2013. All rights reserved.

Friday, April 25, 2014

Designer Swimming Pool Glass Mosaic Tile

Glass tile mosaic swimming pool designer, Paolo Benedetti, discusses yet another possible cause of glass tile cracking.

Thermal Stress

Thermal stresses can be induced into glass tiles when a temperature difference occurs between the edges and the center, or between the surface and the reverse.

The expansion of the over heated center results in tension along the edges.  When these stresses exceed the strength of the glass, it cracks.  Simple enough.

Add to that, irregular edges with manufacturing chips and imperfections, and you are guaranteed to have problems.

Shape, Thickness, Shadows

The thicker a glass tile is, or the larger it is in surface area, the more prone it is to these stresses.  Common logic.

Merely mounting and grouting glass tiles also contributes to this phenomenom.  The opaque grout between tiles, shades the sides of the neighboring tile.  

Thicker tiles only compound this problem by shading even a greater percentage of the neighboring tile.

How do you avoid problems ?

As a rule of thumb, stick with small, thin tiles.  "Ice cube" glass tiles are probably not the best choice for conditions subject to thermal stresses.  Neither are large format tiles - those that exceed 3 x 3.  

Select tiles from a manufacturer who tiles are not chipped, irregular or deformed along the edges - a sure way to inducing cracks.


Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. Visit his website at: www.aquatictechnology.com. All Contents © Aquatic Technology Pool & Spa, 2013. All rights reserved.

Saturday, April 19, 2014

Glass Tile Mosaic Swimming Pool Cracks Defects Expert Witness

The new glass tile mosaics in my swimming pool are cracking.  The pool builder and installer have no idea why...

Myriad of causes

There are actually a whole slew of possible causes.  They could be from any one or combination of the following:
  • Inferior quality glass tile mosaics
  • Failure to follow proper installation procedures for glass tiles
  • Utilizing improper installation materials

Each of the above categories has many possible sub categories - over 50 in total.  That is over 50 singular possible causes of an installation or material failure.  Combine any of them, and you multiply your chances for a catastrophic failure. The more that are violated the exponential chance there is for performance issues.

Bottom Line

Research your installer, the materials and the tile.  The internet contains a lot of valuable information from people who have had real world experiences.  Forget the pretty showroom and home improvement store displays.  

Forget the references provided by your installer - are they really so stupid to provide the names of people who are unhappy with their glass tile mosaic installation?

Start with written specifications that comply with the TCNA and ANSI installation guidelines for glass tile mosaics.  

Even if the tile manufacturer does not have specific installation procedures, these are the standards that your installer will be held to.


Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. 
Visit his website at: www.aquatictechnology.com. All Contents © Aquatic Technology Pool & Spa, 2013. All rights reserved.

Saturday, April 12, 2014

Cracked Swimming Pool Los Gatos Mountains

Owner Knows Best...  NOT!

This was one of those cases, where the owner's wife was a "bossy know-it-all."  She had the where-with-all to hire me as a consultant, yet did not want to hear the advice that I was being paid to provide.

Solution to everything

Just because she was married to a rich and wealthy silicon valley executive, she had a solution to everything.  The pool was originally built on top of a hill, without the benefit of any soils reports (that she could remember).

Her memory was conveniently foggy about the engineering and construction of the pool.  However, she remembered the exact vendor that replacement coping and deck stones could be procured from.  She could not even recall the pool builder, yet knew the gunite and plaster sub-contractors.  Something just "didn't seem right" about her selective memory.  I was already beginning to speculate that this was a very manipulative woman.

Poor planning and execution

By her own admissions, the pool was built atop fill from the excavation of the mansion.  Since then, the fill obviously began sliding down the hill.  

The hill was visibly creeping and slipping, and the pool was moving with it.   Yet, she could not remember if the hillside benefited from being properly compacted under an engineer's supervision.
 (Click on any picture to enlarge it)


Homebrew solution

Without the benefit of a geologist or structural engineer, she figured that if she threw enough of her husband's money at the problem, it would go away.  She concocted a scheme to build a 12 foot tall retaining wall below the pool, to stabilize the hill and pool.  Yet, she was building the wall with geo-blocks without any deepened foundation.  

The surcharges and loads upon the new wall were completely unknown.  And no concern was given to the setbacks from the slope.

Humpty Dumpty

Her pool was what I call a "Humpty Dumpty Pool"- it had fallen, cracked into pieces, and all of the king's horses and all of the king's men could not put it back together again.



Yet, the she had already spoken to a local "epoxy injector" who was willing to inject the cracks.  He was then going to install glass tile mosaics throughout the interior of the pool.

She wanted me to provide a bid for the same scope of work.  I refused.  The pool had structural cracks, the pool was losing water, was out of level and it was built atop questionable soil conditions.

Patient refuses the doctors advice

Even when provided all of the facts, the "patient" (owner) refused to admit that the pool was terminal.  Her retaining wall "fix" was not approved by any engineer to stabilize the hillside, and work was already underway... all without permits.

You cannot save people from themselves

The owner's wife kept pressuring me to concur with her solutions.  I told her that the facts were the facts.  Regardless what the "epoxy charlatan" was advising her, the pool was beyond repair.  Not what she wanted to hear, but the truth.

I decided that regardless of what I told her, she would go off and do what she wanted.  She really hired me in an attempt to validate her erroneous foregone conclusions.  However, I refused to bow to her pressure.




After the remodel project, as the pool continued to move, the cracks returned, new tile mosaics popped loose, her retaining wall began to fail and the vessel began to leak - she would have returned.  Only this time it would be with a lawsuit for providing faulty advice.



Walking away from such clients is the smartest thing you can do.   These people are used to always "having their way."  And when their schemes do not work out, they're always going to seek someone else to blame.

Not me.  Not this time.

At least the doctor got paid.  

And I'll be ready to provide expert witness or inspection services to anyone involved in future litigation over this pool's structural failure.


Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. 
 Visit his website at: www.aquatictechnology.com. 
All Contents © Aquatic Technology Pool & Spa, 2013. 
All rights reserved.

Monday, April 7, 2014

Expert Witness Swimming Pool Bonding Water

Bonding the water 
 
National Electric Code 680 requires that the water of the pool also be bonded.  This means that the water needs to be in contact  with the equipotential bonding grid.

This can be achieved if there is a properly bonded heater, light niche, bronze handrail anchor or metal umbrella sleeve underwater. 

Otherwise, a length of bonded stainless steel pipe or a bonding probe can be added to the plumbing at the equipment pad.

Bonding the surfaces around a pool

Section 680 also requires that the decking, or in the case of a deckless pool or one with concrete paving stones, that the soil surrounding the pool be bonded.  This can be achieved through the use of a copper mesh or a #8 copper wire that enciricles the pool.  The copper bonding loop must be attached to the pool’s reinforcing steel at four locations that are spaced equally around the perimeter. 

Your pool doesn't have rebar?

Vinyl liner or fiberglass pools that do not have reinforcing steel, must have a layer of copper mesh placed below them prior to installation.  This copper mesh under such pools must then connect to the decking loop in four locations, just like a concrete pool.


Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. Visit his website at: www.aquatictechnology.com. All Contents © Aquatic Technology Pool & Spa, 2013. All rights reserved.

Saturday, April 5, 2014

Atherton, Woodside, Palo Alto, Swimming Pool Builder Expert Designer

Low Voltage Lighting is prohibited by law from being adjacent to a swimming pool or spa.

Section 680.23(C) could be changed for the 2014 NEC to permit a special isolation transformer with a ground shield, similar to the underwater luminaire transformer, for aboveground low-voltage lighting systems in proximity to the edge of a swimming pool. Until the change is submitted and processed, low-voltage lighting must not be located closer than 10 feet horizontally from the edge of the pool or 12 feet above the pool. - See more at: http://www.ecmag.com/section/codes-standards/waters-fine#sthash.cDzLMcen.dpuf
Section 680.23(C) could be changed for the 2014 NEC to permit a special isolation transformer with a ground shield, similar to the underwater luminaire transformer, for aboveground low-voltage lighting systems in proximity to the edge of a swimming pool. Until the change is submitted and processed, low-voltage lighting must not be located closer than 10 feet horizontally from the edge of the pool or 12 feet above the pool. - See more at: http://www.ecmag.com/section/codes-standards/waters-fine#sthash.cDzLMcen.dpLow voltage landscape lighting cannot be installed within 10 feet horizontally or 12 vertically of a swimming pool, spa or hot tub.
Prohibited by Law
 
The National Electric Code is the law across the United States.

2011 NEC Section 411.4(B) prohibits the low voltage systems within 10 feet of any pool, spa or hot tub, unless it is specifically permitted by section 680 of the NEC. 

What can I do?

NEC 680.22(C) defines the requirements for low voltage lighting.  It does not specifically describe low voltage lighting fixtures or components that are not underwater light fixtures.

NEC 680.23(A)(2) specifically discusses underwater illuminares, and does not make any mention of illuminares that are out of the water.

Because low voltage lighting out of the water around the pool are not specifically defined anywhere in Section 680 (as required by NEC 411), they are still prohibited.
 

So, How do you provide accent lighting around a pool?
 
Utilize innovative concepts and methods.

I have developed some compliant "work arounds," that are 100% compliant with the NEC.

Call me.  I'd be happy to design a system that is code compliant for your project.


Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: info@aquatictechnology.com or 408-776-8220. Visit his website at: www.aquatictechnology.com. All Contents © Aquatic Technology Pool & Spa, 2013.
 All rights reserved.