Sunday, December 22, 2013

Swimming Pool Designer Structural Engineer

Hiring a Swimming Pool Designer VS a Structural Engineer to design your new swimming pool project?


Let's face it, most structural engineers have the creativity of a bag of sand.  While useful for a specific purpose, their usefulness in developing a creative or innovative design is limited.  Engineers are focused on what holds it all together.

Designers usually have a background in the elements of design, such as materials, textures, color, scope and scale.  Their plan will have placed thought behind the seasonal sun and shade patterns, prevailing winds, lines of sight, foot traffic patterns and peering eyes of the neighbors.  An educated designer will bring their decades of experience and education about fountains, pools and architectural history into play.  While the engineer will rely on their computer and sliderule.


A designer that does not have a background in building pools, may come up with unique ideas, but will have no idea if they are even feasible or able to be built.  You may become excited about an element of the design, only to be told that it cannot be done.

A creative and experienced designer with decades construction experience will be able to develop a project that meets a clients needs, as well as being functional, practical and executable.  When faced with engineering challenges, they will be able to suggest to the structural engineer options for maintaining economical feasibility.

Best of Both Worlds

How do you get the best of both worlds?  Hire an experienced swimming pool designer/builder to consult on the creation of your design.  The completed architectural drawings are then sent to the structural engineer.

The structural engineer is utilized to detail the concrete and steel to hold it all together.

Creativity, functionality and durability meet.

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

Sunday, December 15, 2013

Spalling Glass Tile Mosaics Expert Witness

Cracking glass tile mosaics investigated by expert witness Paolo Benedetti

Shards of Glass

Imagine walking into the shower or steam bath, onto hundreds of shards of glass... Not the way anyone I know wants to start their day!  Now imagine being greeted by shards of glass on the floor every single morning!

I was asked to investigate a product liability issue of fracturing glass tile in a steam shower.  The contractor was being accused of installing the tiles incorrectly - tiles the homeowner provided.  It turns out the tiles were installed correctly.  The problem was the glass mosaic tiles themselves!


Glass mosaic tiles at rest will assume a temperature close to that of their environment.  However, when subject to a blast of hot water or steam, the surface temperature is instantaneously increased.  All the while, the middle and back of the tile are still at the room temperature.

The sudden expansion of the surface layer of glass, causes it to explode.  Small divots of glass, like those caused from the impact of a projectile, pop off of the surface... and onto the floor.

Name Brand Designer

These tiles, while from a name brand designer who licenses her name for use on various products, are actually made in China.  And surely from dubious quality raw materials and under loose quality control standards.


How do you prevent from becoming the victim of such inferior glass tile mosaics?  First, think thin.  The thinner a tile is, the faster it can respond to changes in temperature.  The chances of such fracturing is diminished significantly.

Inquire if the tiles are rated for thermal shock to the extremes they may be subject to in a steam bath or shower (especially if you have a "instant hot" shower).

Or, obtain a sample and perform some rudimentary testing of your own at home.  Heat them in an oven to the temperature of the steam bath and then submerge them into 75-80ºF water.  Or chill them and then drop them into boiling water.  Be sure to to protect yourself with the appropriate safety gear.  If they crack... maybe you should delve deeper into their suitability.

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

Sunday, December 8, 2013

Clouding and discoloration behind glass tile mosaics

With glass tile mosaics increasing in popularity, so have the complaints about dark spots, discoloration, clouding and color rendition.
Installation Practices

Proper installation practices for glass tile mosaics are time consuming and expensive.  The cost for labor and setting materials in a pool or fountain can run from $35-100 per square foot - not including the cost of the tile!

In an effort to bring the installation costs of glass tile in a swimming pool within reach of those with limited means, many installers take shortcuts.  These shortcuts include direct setting tiles, bonding them to incompatible substrates, using inferior setting materials or rushing the installation.

Published Standards

In 2005, in response to many consumer complaints and installation failures, the tile industry created minimum standards for glass tile installations.  This committee was comprised of glass tile manufacturers, manufacturers of setting materials and tile installation contractors.  The results were the 2005 ANSI Standards A108.14 - A108.16 - Practices for the Installation of Glass Tile Mosaics.

These standards were promptly adopted by the Ceramic Tile Institute of America (CTIOA) and the Tile Council of North America (TCNA).

In fact, CTIOA has since promoted the ANSI standards as the ONLY acceptable methods of installing glass tiles.

Some third world and foreign tile manufacturers publish installation instructions that conflict with these standards.  Installation contractors need to be aware that failing to follow accepted and published industry standards will make them liable in the event of any installation failures.

The bottom line is that the installer needs to follow the most stringent standards that apply to their installation.  YES, that is even if a manufacturer allows for a faster, cheaper and easier method.

Trapped Moisture and Voids 

Moisture, voids or blemishes behind translucent (see through) glass tile mosaics will show through the tiles as a discoloration.  The discoloration can be spot behind a single tile, a random assortment of tiles or an entire installation.  They are unpredictable, occur randomly and may only affect a small portion of a project.

Voids, trapped moisture and blemishes occur behind the tiles from the following installation errors and mistakes:
  • the bondcoat skins over before the tiles are set (poor bond, loose tiles & voids)
  • using the improper direct bond (two step) installation method
  • notches left in bondcoat
  • too thin of a bondcoat
  • utilizing dark colored grouts - which are visible through the sides of translucent tiles
  • insufficient embediment into bondcoat
  • too much water in the bondcoat 
  • ground water weeping into the shotcrete from the soil
  • grouting too soon after setting (the back buttering with grout method may in fact trap moisture)
  • insufficient curing of the mortarbed (leveling bed)
  • a bondcoat that experiences shrinkage (and results in voids)
  • utilizing grey cements -which darkens when wet and will be visible through the sides of the tiles if allowed to ooze up between them
  • failing to install a waterproof membrane
  • filling the pool too soon
  • failing to shade the tiles from the sun prior to filling the pool
  • failing to protect the pool from rain (or snow or irrigation water prior) to filling the pool
I am not going to discuss each of the above conditions and why they cause discoloration behind the tiles.  Individually or in combination they can lead to visible setting flaws.


There are tests that expert witnesses utilize when investigating complaints of discoloration behind translucent glass tile mosaics. These tests analyze the visible color variations, composition of the setting materials, sheer strengths (pull off resistance) and moisture contents.

Samples removed for testing must remain in the same condition as when they were installed.  If they were under water, they must remain wet.  Allowing the samples to dry out will change the characteristics of the sample, rendering their evaluation useless in determining the cause.

Learning Process

The final result of any project evaluation, should be the education of the party responsible for the installation.  Incorrect installation procedures, improper setting materials or a combination of them, are responsible for most complaints of discoloration.  

Installers have been known to blame minerals in the water, airborne mold spores and poor pool water chemistry for causing these discolorations... anything but owning up to their misgivings.

Through strict adherence to the published installation standards and practices, you can be guaranteed a flawless glass tile mosaic swimming pool.

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

Glass Tile Mosaics Using Direct Set Method

The Direct Set Method of installing glass tile mosaics IS NOT an approved method.

What is the Direct Set Method?

The Direct Set Method (aka: two step method) is an economical and rapid installation method, reserved for ceramic or stone tiles.  After installation and curing of a mortar leveling bed, a layer of mortar is applied to either the mortar bed or the back of the tiles.  The tiles are then pressed onto the cured leveling bed.

Standards Prevail

Many foreign manufacturers of glass tile mosaics provide instructions that follow third world standards.  Simply stated, they do not comply with the science and standards that apply in modern countries.

Following simple instructions to mix white cement and sand to create the setting bed, will not ensure material that is compliant with the ANSI  performance standards.  The sheer strength, permeability and compressive strengths of this material will be totally unknown.  

More critically, glass tile is susceptable to cracking when setting materials experience shrinkage.  Shrinkage is unpredictable with field mixed materials.  Shrinkage places glass tiles under compression.  This stress is relieved by a glass tile as a crack.

ANSI Standards A108.14, A108.15, A018.16

In 2005, the American National Standards Institute (ANSI) developed specific standards for the installation of glass tile mosaics.  These standards are very precise.  None of these standards allow for the use of the Direct Set Method when setting glass tile mosaics.

These ANSI standards were developed in conjunction with the Ceramic Tile Institute of America (CTIOA) and the Tile Council of North America (TCNA).  Both CTIOA and TCNA promote the ANSI standards as the ONLY APPROVED METHODS OF INSTALLING GLASS TILE MOSAICS.

While the Direct Set Method of installing glass tile mosaics may be cheap, fast and easy - it is not permitted in North America.

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

Saturday, November 30, 2013

Swimming Pool Bonding Grid

Gounding and Bonding ARE NOT the same thing!

I frequently hear the incorrect statement that "grounding and bonding are the same thing."  Though closely related and even interconnected, they are not the same thing.

Purpose of Bonding

Bonding is installed to ensure that every metallic component of a swimming pool has the same electrical impedance - that is, the same resistance to electricity.  The impedance of a bonding grid should be ZERO.


Redundancy exists in many components attached to a bonding grid, to ensure that the impedance is exactly the same for all attached components.

A case study:
A large pool contained numerous light fixtures housed in PVC niches and connected to PVC conduit.  

Every niche had a bonding wire connecting it's exterior bonding lug to the reinforcing steel in the shotcrete.  

None of the niches had the required interior bonding wire installed.

The impedance reading of all of the niches varied between 250 and 500 ohms, except for one.  That one niche had 0 ohms of resistance.  Why?

The bonding wire from the equipment pad was connected to the clamp on the reinforcing steel, then continued down to the bonding lug on the back of that one niche.  Yes, it also happened to be the niche closest to the equipment pad.

Though all of the other niches were connected to the bonding grid, the concrete and steel created resistance between those niches and the one niche with the "home-run" bonding wire.

The purpose of the internal insulated green #8 bonding wire, is to provide another path to ensure that the impedance is and remains at -ZERO- .

Fatal Path to Ground

All of the grounding wires at a property are interconnected.  At the service entrance (electrical meter), there is a grounding rod.  It's purpose, is to discharge any stray voltage. 

However, the grounding rod may not always present the best source of ground for electricity.  The hundreds of yards of wet steel and concrete in the backyard may actually be a better ground.... so electricity takes the path of least resistance & discharges itself into the earth through the shell of the swimming pool.  Though the water may in fact be energized, a proper bonding grid keeps it all safe.

Now, along comes a swimmer.  They touch a metallic part of the swimming that is properly bonded back to the pool steel & bonding grid.  Though the swimmer is a part of the "loop" they do not feel anything - because the electricity is not discharged into the earth (it loops back).

Now, the swimmer touches a metallic component that is not properly bonded or has a high impedance.  The swimmer is now in the direct path of the electricity as it discharges into the earth through the metallic component.  The swimmer is shocked - maybe even fatally.  Why?  They are in the path to ground for the electricity.

When there is a loop and the impedance is zero, humans are not affected.  But, when the human being is a part of the circuit as the electricity is discharged into the earth - they are shocked.

Simply stated:  The purpose of a bonding grid is to ensure that all of the components have the same potential (impedance) to ground.

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

Sunday, November 24, 2013

ACI 318-11 thicker stronger shotcrete pools

ACI 318-11 requires that the shotcrete walls on salt water pool be increased in strength and thickness.  Shotcrete is defined as either the wet or dry process of pneumatically placing concrete.

ACI - The American Concrete Institute

ACI is the definitive expert on concrete.  So much so, that they publish a myriad of standards that relate to concrete and it's use.

ACI Standard 318-11, "Building Code Requirements for Structural Concrete" has been directly incorporated into the International Building Code (adopted by 48 States, except Minnesota) and by the California Building Code.  This effectively makes it the law of the land. 

ACI 318-11 changes the requirements

ACI 318-11 redefined the parameters of the required coverage of concrete required over the reinforcing steel.  Prior versions of ACI 318 were ambiguous as to what was actually defined as sulfate or corrosive conditions.

ACI 318-11 establishes the additional shotcrete protection required when exposed to defined levels of sulfates, water containing chlorides (salts) and permeability.

ACI 318-11, Table 4.2.1 indicates that shotcrete swimming pools are required to meet the criteria for Permeability - P1 (condition defined as: "in contact with water where low permeability is required") AND Corrosion Resistance - C2 ( a condition defined as: "concrete exposed to moisture and an external source of chlorides from
deicing chemicals, salt, brackish water, seawater, or spray from these sources").

The resulting P1 and C2 classifications require specific mix design ratios (ACI 318-11, Table 4.3.1).

ACI 318-11, Table 4.3.1, P1 classification sets a maximum water to cement ratio (w/cm2) of 0.50 and a MINIMUM 28 day compressive strength (f'c) of 4,000 PSI.  While the C2 classification establishes a maximum water to cement ratio (w/cm2) of 0.40 and a MINIMUM 28 day compressive strength (f'c) of 5,000 PSI.

Therefore, any swimming pool that is going to be treated with sodium compounds is REQUIRED to have a maximum water to cement ratio (w/cm2) of 0.40 and a designed compressive strength (f'c) of 5,000 PSI.  Sodium compounds utilized in swimming pool sanitization include sodium chloride (chlorine), sodium bromide (bromine) or sodium (salt-electrolysis chlorination).

The C2 classification (Table 4.3.1) further specifies that the requirements of ACI 318-11, 7.7.6 "Corrosive Environments" be met.  Section 7.7.6 states that the coverage over reinforcing steel shall not be less than 2 inches for walls and slabs subject to such corrosive environments.

Structural Engineers & Building Departments

Many structural engineers and building departments do not abide by the requirements of ACI 318-11.  They either attempt to justify design criteria less than the standards, are not versed on the most up to date requirements or simply fail to comply with the codes.

When there is an issue of structural integrity on your pool, the most recently adopted version of the IBC, CBC or ACI standards will apply in court, whether or not they were enforced by the engineer or building inspector.

Do you want to be left hanging with a structural engineer who will have to defend his decision to design a structure that was below the requirements of the building codes?  
Do you want to take the risk that he will be able to convince a jury of lay people that a weaker structure is acceptable?

I thought not!

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

Tuesday, October 22, 2013

Safe Skimmer Equalizer Lines

Skimmer equalizers should be required when skimmers are the sole source of suction for a pump.

We have proven that main drains are not required for proper circulation.  It is irresponsible to suggest the elimination of equalizer suction outlets as well, and thereby the protection for multi-thousand dollar pumps and proper water sanitization.

Low Flow Conditions

Low flow situations can occur from low water levels, weirs that become askew from kids playing with them, excessive waves, debris (goggles) and wear.  The baskets can become blocked due to latex bathing caps, inflatable toys, paper napkins, leaves or other unexpected debris.

When skimmers are the sole source of suction for a pump, the lack of equalizer suction outlets will deadhead the pump or cause a run dry condition, if the skimmers become clogged or inoperative.  The expense of repairing damage to pumps from "run dry" conditions, will become the burden of the designer or installer, because the damage is easily preventable through the use of equalizer suction outlets.


Most skimmers have flow ratings of only 75 gpm.  Skimmers should always be installed in a minimum of pairs, even more if the designed flow rate of the system demands it.   

Equalizers should be installed in a configuration that limits their line velocities to no more than 3 FPS and provides suction entrapment protection in compliance with VGBSA (some jurisdictions have a restriction of only 1.5 FPS).  Since anti-entrapment covers are derated when wall mounted, more than two equalizer inlets may be required to maintain a compliant flowrate.  Equalizers suction outlets should be installed with a minimum of three feet of separation and with the proper sump configuration.
Don't merely rely on Variable Speed Pumps

Variable speed pumps have an inherent design flaw.  When they shut down in a “self protection mode” due to loss of prime or low flow conditions, they do not provide an alert to their attached control systems or a remote control panel.   

Critical filtration and sanitization systems may become locked out for extended periods of time without any indications or warning signals.   In commercial pools or spas, this could quickly result in unsanitary and unsafe water conditions.  When system flow is critical to prevent facility damage (e.g. operation during freeze conditions), inoperative pumps are unacceptable as more severe damage to the facility may occur.

The Solution is Inexpensive
Properly installed with float valves and equalizer line check valves, equalizers will be dormant most of the time.  Only an equalizer check valve (pop-it check valve) in the skimmer can prevent suction on the equalizer line.  A float valve by itself will actually divert some suction to the equalizer lines.  

Therefore, float valves AND equalizer check valves should be utilized together, to prevent suction on the equalizer lines, except in critical skimmer low flow situations.

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

Sunday, October 20, 2013

Galvanic Corrosion and Electrolysis in Saltwater Pools

When galvanic corrosion, electrolysis or staining occurs in saltwater pools, a SACRIFICIAL ANODE is not the placebo everyone is seeking. 

Marine Applications

On a boat, a sailor does not care if the anode erodes, or if the anode's metals dissolve into the water (ocean).  The anode on a boat is a lot cheaper than the wiring, prop or shaft.  It prevents the corrosion of the precious components, by SACRIFICING itself instead. 

Swimming Pool Application

But, placing a sacrificial anode in a swimming pool is doing the same thing as on a boat.  One is merely offering a SACRIFICIAL metal for the galvanic corrosion to attack, instead of the precious components. 

So instead of plating surfaces with copper, you will be plating them with zinc or magnesium from the anode.  The sacrificial anode will save the copper, but it will not stop the staining or plating of the stainless steel components.  That will NOW occur with the metal from the anode.  This is exactly why anodes need to be periodically replaced - they are sacrificed.

Sacrificial anodes are not the solution to the damage caused by galvanic corrosion or electrolysis.

Bonding Grid

The equipotential bonding grid does not prevent galvanic corrosion.  In fact, if there is stray voltage finding it's way to the pool through the property's CONTINUOUS GROUNDING SYSTEM, the equipotential bonding grid may actually be feeding voltage to the pool's metallic components. 

The bonding grid can actually function as either the electrode or cathode, depending if there is stray voltage present on the property, thereby energizing the bonding grid.  Alternatively, it can be providing a path to ground, where the equipotential bonding grid and the grounding grids are intentionally cross connected - pumps, heater's, panel boards, etc.

A Solution

For these very reasons, many pool builders that I know and I, have ceased installing salt systems.  We now promote the micro-dosing of bleach via a ORP/pH Controller, augmented by a commercial sized ozone generator and contact chamber.

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

Wednesday, October 9, 2013

Shotcrete Swimming Pool Reinforcing Steel Placement

Reinforcing steel - the bones that hold the body together.

Why does shotcrete require reinforcement?

Concrete is very high in compression, but week in tension.  That means that concrete does not flex well.  However, steel is very high in tension and weak in compression.  So this is a marriage made in heaven - each compliments the other.

Placement - where does it go?

The placement of the reinforcing steel within the shotcrete wall is very critical.  The structural engineer may specify that the steel be installed closer to the outside or the inside of the concrete, depending upon the anticipated loads.

Incorrect placement of the steel will result in a structure that is not as strong as the engineer intended.

Lap Splices - Contact or Non-Contact?

Pieces of reinforcement steel come in finite lengths.  This means that splices will need to occurBut how do you to create proper splices?

Remember, the steel exists to reinforce the concrete.  Therefore, the bars of reinforcing steel do not have to make contact with each other when they are spliced.  Because shotcrete is applied with air at tremendous velocities, the steel needs to be arranged to allow the concrete to completely encase the reinforcement.  If bars begin to create congestion in an area, then it is almost guaranteed that there will be voids and honeycombs behind them.

ACI 506R-95, Guide to Shotcrete, Section 5.4.2 states that non-contact lap splices shall be utilized to prevent this very occurrence.  This is the standard and code across the United States, since the American Concrete Institute (ACI) standards have been adopted and incorporated into the International Building Code (IBC).  The IBC is the building code for the entire United States.  

Non-contact lap splices shall also be spaced so they do not exceed the ACI guidelines.  Otherwise, excessive spacing could create unreinforced areas of concrete.

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

Wednesday, October 2, 2013

Concrete Coloring and Pigments

Concrete pigments for coloring concrete

Quality Materials

In swimming pool environments, poor quality pigments in concrete will be susceptible to fading and discoloration.

There are many criteria that go into quality pigments.  The size of the fines (granules), purity of the oxides, quality control of the color and synthetic or natural ingredients, all contribute to the durability and rendition of the color.

Use and experience with various brands, will identify the best performers.

Water Chemistry

Improper maintenance of the swimming pool water chemistry, the extremes can also cause aggressive or scaling conditions.

Maintaining water chemistry records is a great way to prevent water chemistry from being blamed as the cause of concrete discoloration.


Properly sealed concrete will resist most chemical attacks or poor water chemistry, long enough to clean up the spill.  Penetrating sealers are the best, as they let the concrete breath, resist most stains and do not change the sheen of the surface.  They also do not contribute to slippery conditions.

Use quality materials that are specified by experienced consultants or contractors.

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

Wednesday, September 11, 2013

International Aqua Design - suspected defects, now what

You suspect defects with your international aqua design, now what? It's time to hire a swimming pool expert witness to sort things out.

Something just isn't quite right

Your pool has been completed.  It doesn't operate quite right, tolerances vary, things are out of level, the equipment is noisy and the masonry and concrete is beginning to crack.  Your international aqua designer and builder has an excuse for every issue you raise.  You're not an expert but you know that they're blowing smoke.  You can just "feel it."

Few people actually listen to that "sixth sense," that tells them when something just isn't right.  And the people who are trained to listen to that sixth sense, police officers, special forces operators and trained interrogators, are naturally suspicious to begin with.  Go with your gut feeling - your instincts are usually correct!

Make your demands reasonable

A property owner needs to be reasonable.  They need to provide their contractor with sufficient time to remedy any defects.  The owner needs to put everything into writing.  Conversations can be debated - he said, she said.

Be professional, courteous and non-emotional.  List the defects that you are aware of, what you want done and the completion deadline you seek.  First class mail is usually sufficient.  If there is already some animosity, then certified mail - return receipt tells them that you mean business and are documenting everything.

You should also involve your architect, landscape architect or your watershape consultant.  They may be able to inspect the project for compliance with their plans.

Failure to reply or comply

If the contractor fails to reply or refuses to address the issues, then it is probably time to consult with an attorney and a swimming pool expert witness.

Your attorney can discuss with you strategies and tactics.  

Once the swimming pool expert witness has performed their cursory inspection, they will prepare a list of patent defects (obvious defects).  From their investigation they may begin to suspect latent defects (concealed defects).  Those may require invasive and non-invasive testing.

Collecting your documents

The swimming pool expert witness will want to review everything that you have in your possession:
  1. initial proposals, bids, concept drawings
  2. change orders
  3. contracts, specifications, equipment & material lists
  4. a list of sub-contractors and their lien releases
  5. plans and structural engineering
  6. permit inspection card and any city documents (regarding barriers, special inspections, inspection schedules, etc.)
  7. EVERY photograph and video that you took during construction (burn to a disc)
  8. copies of any communications between you & the builder (emails, letters, telephone call logs, etc.)
  9. any calendar or diary of their construction progress, dates of major milestones, no show days, etc.
  10. cancelled checks or receipts for payments
  11. any other documents (packing slips, owners manuals, instructional papers, use/care guides, pre-liens, correction notices, etc).
The swimming pool expert witness will review all of the documents.  Those documents will help to assemble a project timeline.

From your detailed and extensive collection of digital photographs, they will be able to zoom in on suspicious items.  Items and locations that may include potential latent defects are identified.  Those items may warrant additional inspections.

Once the list of actual damages (patent and latent) has been identified, the cost of repairs can be estimated.  Then your attorney will take over and negotiations begin.

Many times swimming pool expert witnesses will be retained following the case settlement to observe any corrective measures.  Though these repairs are usually performed by a third party contractor, the expert witnesses has intimate knowledge of the defects and the project that allows them to provide guidance and direction on the owner's behalf.

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

Tuesday, September 10, 2013

Gunite Shotcrete swimming pool steel

How does a swimming pool expert witness verify the steel placement on a swimming pool that has already been built?

Construction Documentation

Usually, property owners have lots of photographs of their swimming pool while it was under construction.  These are very helpful, even if there is not a ruler or scale in the drawing.

Usually there is an object of a known dimension shown in an image.  From that known object's dimensions, the expert witness can establish a scale for the image.  That image scale is then utilized to judge the proper spacing and placement of the steel reinforcement.

Take lots of high-resolution digital pictures!

Non-Destructive Testing

There are also devices that allow an expert witness to "see" inside the wall.   These radar devices look into the concrete to determine it's placement and depth under the surface.  Think of them as high tech stud finders.

Destructive Testing

Like it sounds, these tests involve destroying small areas of the structure.  These are usually limited to four or six inch diameter borings of the concrete.

Sometimes, a larger area is required to be opened.  These are usually limited to cases when the soils or material under or around the pool are called into question.

In one instance, the side scanning radar indicated one abnormally large diameter piece of reinforcing steel in the shotcrete.  Opening up this area with jackhammers revealed an 3/4 inch black iron gas pipe routed in the soil under the pool.

The pool builder took the shortest path by installing a pipe without any corrosion protection directly under the swimming pool.  After 8 years, the line was already so corroded a pen knife pierced the pipe.

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

Friday, September 6, 2013

Aqua design international disaster

An aqua design group's - international disaster waiting to happen.

Experience and Training

An aqua design group's international failure at providing competent plans, nearly caused a castastrophic project failure.  This firm (that is really a landscape architecture firm) did not inherently possess the skills or knowledge to design aquatic facilities.  A review of their plans, associated construction details and project specifications bore this out.  

A qualified pool builder builder would have to significantly modify the aqua design group's substandard plans to meet the building codes, industry standards and acceptable trade practices.  

This would mean that the project could not be built for the cost projections provided by the international aqua design group.  The property owner would be hit with change orders and cost over-runs, just to make the project code compliant.

Plan review reveals deficiencies

While reviewing an international aqua design group's plans, I happened upon many deficiencies that could have been catastrophic, even deadly.  The Arizona based landscape architecture firm that promotes itself as "international aquatic designers and planners" had designed a perimeter overflow pool and underground equipment room for a high profile client.

Personnel Safety

The underground room lacked the required "confined space" ventilation, required by OSHA, to allow personnel to occupy the below ground vault.  The access ladder, light switches and lighting were also not OSHA compliant.

Electrocution Danger

The equipment room did not have any drainage or sump pumps to protect the room from flooding.  The international aqua design group even specified that the equipment was to be mounted directly on the floor!  And, NO GFCI protection was specified for these components.

In the event of a leak or faulty plumbing, the electrical equipment room would have flooded.  The water would have equalized with the water in the vessels.

Electrical and mechanical equipment would have become submerged.  This would not have only destroyed the equipment, but could potentially electrocute someone climbing into a flooded room.

Lack of Equipment Ventilation

Electric motors, pool pumps, heaters and other pool equipment require cool air to maintain the proper operating temperatures.  Without any provisions for cool air, the equipment will operate inefficiently, experience shortened lifespans and eventual overheating.

Auto-Fill Design

Contrary to acceptable trade standards and practices, the auto-fill line was designed to inject the fill water into the gutter of the pool.  The placement of the fill line in such a manner would have cause water to spray out of the gutter, creating a lot of noise and visual distraction.

Lack of Surge Tank

Though tight on space, the site was sufficient to allow a properly sized and built surge tank.  Instead, the international aqua designer chose to utilize the gutters as the surge tank.  Such a design would flood the gutters from bathers displacement or wave action - rendering the gutters ineffective.

Lack of Hydraulic Calculations

No hydraulic calculations, line velocity specifications or other design criteria were provided with the plans.  The line velocities at the suction inlets (drains) were not compliant with the codes.  The selection of pipe sizes appeared arbitrary.

After performing hydraulic calculations, it was determined that the international aqua design firm's pipe specifications were grossly undersized for the specified pumps.

No Protection against flooding

The equipment room was not provided with an absolute failsafe method of preventing flooding.  Inexpensive techniques are available to prevent flooding or back siphoning of the return lines, in the event of a check valve failure.  These devices were simple ignored.

Lack of Serviceability

The equipment room was not provided with a means to service the equipment without draining the pool!  Because the plans omitted shut off valves on every pipe, the pool would have to be drained to perform routine maintenance such as cleaning filters, repairing pumps or cleaning pump strainer baskets.  A waste of precious water, chemicals, labor and money!

Maintenance & Cleaning

Provisions needed to be made to allow for vacuuming of the various vessels.  Usually international aqua designs include dedicated vacuum ports in every vessel, that function as "central vacuuming" systems.  These are critical for overflow pools that lack skimmers.

Generic Mail Order Structural Engineering

To add insult to their work product, the aqua design failed to provide site specific structural engineering.  The engineering was not sufficient to withstand the soil and site conditions present.

The aqua design firm simply purchased some engineering from a catalog and forwarded them to the client.  This was a violation of the California Building Code (CBC) and the International Building Code (the nationwide building code).

Lack of Proper Licensing

Adding a final insult, the international aqua design firm was located out of state, and was not licensed to design or build projects in California.  The were not California licensed engineers, architects or contractors and therefore are prohibited from designing projects in the state. 

Landscaping firms that have turned into aqua design groups, hardly  possess the qualifications to properly design and build swimming pools - let alone resorts or public facilities.

Accreditation and Certification

There is only ONE accredited program (IACET) for the training and education of swimming pool designers - and that is from the Society of Watershape Designers.  To date only 35 individuals have completed the rigorous course of study to become SWD Certified.

Hiring an SWD Certified Designer ensures that your project is designed with your safety and best interests in mind!

Contact the Author:
Paolo Benedetti, BS, SWD Certified 
Aquatic Technology Pool and Spa 
phone: 408-776-8220. 
Visit his website at: 
All Contents © Aquatic Technology Pool & Spa, 2013. 
All rights reserved.

Wednesday, September 4, 2013

Swimming Pool Expert Witness - Honesty

Honesty from a swimming pool expert witness is paramount!

An Issue of Credibility

False claims of experience by a swimming pool expert witness will only serve to impeach their credibility.

There are a number of swimming pool expert witnesses who are claiming to have been involved in the design, engineering or construction of tens of thousands of swimming pools.

Delve into the Facts

Was the expert witness the principal of an "engineering mill," that sold generic pool plans via mail order to anyone with a checkbook?  Does that permit them to claim those as experience? Claiming to have been involved in every one of those projects? Hardly!

Was the expert witness the president of a large franchise swimming pool company?  Because they delivered generic engineering to their franchisees, do they get to claim that as "involvement?" Does that allow them to claim that they were involved in every project that their independent franchise owners built?  Hardly!

Issues of Quality

Are there issues of quality or compliance surrounding pools build using those generic plans?  

The issuance of such plans by a licensed engineer without reviewing the site or soils conditions, is a violation of the International Building Code (the USA's National Building Code).  Structures must be designed to withstand the site conditions - something that the structural engineer cannot do without reviewing a soils report or the site conditions.

Have any projects that utilized those generic plans ever experienced structural failures?  
Were those failures due to the inadequacies of the plans or the lack of review of the site or soil conditions?  
Maybe the plans that were provided were inappropriate for the conditions that were present?
Were there quality or construction defect issues with any of the pools built by franchisees?  

If an expert witness is going to claim those projects as their "qualifying experience," then don't they also have to assume the failures associated with those very same projects?

It's all a matter of veracity.

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

Monday, September 2, 2013

Concrete Filling Drilled Caissons - Don't just let the concrete fall

Filling drilled caissons with concrete - do not just let the concrete fall!

Free Fall

Recently, I was asked to weigh in on a project where the methods for placing concrete into drilled caissons were under debate.  

The concrete contractor insisted that the concrete could be dropped from the surface down into the 40 foot hole.  The swimming pool contractor did not feel comfortable with that, but did not know of any standards that dictated otherwise.

American Concrete Institute (ACI)

The ACI publishes a myriad of concrete standards.  Most issues regarding concrete, are discussed in their standard ACI 318.  ACI 318 has been adopted and incorporated into the International Building Code (IBC) as well as the California Building Code (CBC).  The IBC is the basis for building codes relating to concrete, that have been adopted across the nation.

ACI 318 states that concrete should be placed as close to it's intended location as possible.  So, in the case of drilled caissons, that means filling the hole from the bottom up.  The weight of 40 feet of 3-4" concrete filled hose is unwielding.  Usually a crane, backhoe or concrete boom is required to fill such deep holes.

California Building Code

The CBC is a little more compromising.  It allows for the concrete to fall no more than 6 feet.


Why is there any concern at all?  Separation.

If the concrete is allowed to fall a significant distance, the aggregate separates from the concrete.  A homogenous mix is not delivered to the final resting place.  Pumping the concrete from 40 feet also allows the concrete to bounce off of the reinforcing steel, also separating the aggregate from the cement.

To ensure that the specified mix design is delivered as specified, precise placement practices are critical.  

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

Sunday, September 1, 2013

Swimming pool expansive soils structural design

Designing swimming pools to withstand expansive soil conditions

Expansive Forces

Expansive soils are found all across the United States and in many parts of the world.  The energy that they can place upon a structure is immense.

The concern with swimming pools is that the soils around the pool will swell and place an inward force upon the shell (called lateral pressure).  The expansive soils literally squeeze the pool to death, cracking it.  Expansive soils under a pool can push it right out of the ground.  And usually this is not an even force, so the pool ends up being out of level, creeps or moves, or the floor cracks.

Once a pool begins to leak, that water saturates the expansive soils making the situation even worse.

May the force be with you

Usually there is little concern about expansive uplift, as expansive soil deposits are usually only a few feet thick.  The act of excavating the pool, removes the expansive soils from beneath the pool shell.  This eliminates the vertical uplift concerns.  In these instances, the pool can be designed to overcome the inward pressures from swelling soils that remain around the walls.

Bench Pressing

Where the expansive soil deposits are deeper than a few feet there are a few options.  Left unchecked, the expansive soils will bench press the pool out of level, potentially cracking the floor.

Over excavation is the least expensive.  If the expansive soils are a reasonable depth, they may be simply removed.  The hole is then brought back up to the required depth with an engineered fill.  The engineered fill can be a cement slurry or imported and compacted road base.  From then on, it is construction as usual with fortified walls (to address the expansive soils around the walls).

In areas with unreasonably deep deposits of expansive soils, the options begin to get expensive.  The most common method is to isolate the floor of the pool from the effects of the swelling soils.  The pool is usually placed upon a series of drilled caissons and supported on grade beams.  The soils between the grade beams are removed and filled with a "void form."  

A void form is comprised of layers of cardboard or EFS foam blocks.  They are used to support the concrete until it is cured.  Eventually the cardboard void form decays and shrinks, leaving a compressible voids or pockets under the pool.  The EFS foam blocks are designed to compress and absorb the energy of the swelling soils.  Not to worry, as the pool is actually supported on the drilled pier foundation.  If the expansive soils swell, they move into these voids, leaving the pool unscathed.

Isolating the Walls

Some soils engineers are over concerned about isolating the walls of the structure from these expansive forces.  This can also be achieved through the use of EFS blocks.  Since they do not decay like void forms, they will continue to support the soils and sidewalks above them.  In the event of compressive forces, they absorb the energy, yet still support the surfaces above.


Keeping the soils around the pool dry, is of course the easiest course of prevention.  Maintaining the caulking in expansion joints and not allowing the decks to drain off into the surrounding planters, will assist in keeping the decks level and the pool structure sound.  

It is best to collect the water on the pool decks and route it a safe distance away from the pool, where they cannot flow back under the pool or decks. Deepened turn down footings around the edge of a patio slab will keep any irrigation water from flowing back under the slab through the base rock material.

This is why you need a soils report before embarking on the structural engineering design for a swimming pool.

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

Wednesday, August 28, 2013

Obtaining swimming pool concrete cores

Obtaining concrete cores from a swimming pool, spa or watershape for the purpose of testing the in-situ (in place) strength requires expert witness supervision and adherence to sampling and testing standards.

Where to core

The locations on where to obtain the samples should be chosen to obtain a representative sample of the placed concrete.  Areas where inexperienced shotcrete operators would allow the accumulation of rebound and trimmings should be tested.  Walls and vertical surfaces should be tested as well, to ensure proper shotcrete placement and correct steel encapsulation.

Core size - Diameter & Length

The testing standards require that the ideal length to diameter (l/d) ratio should be 2, and in no instance less than 1.  Therefore, if the shell is 12 inches thick, the core diameter should be 6 inches.  An 8 inch thick shell would require a core diameter of 4 inches.


The coring machine should be mounted to the surface or of such mass, that it does not move or allow the diamond core bit to wobble.  Wobbling can impart stress into the core sample.

The core bit must be water cooled during the coring operation.  This may saturate the outer surface of the core sample.  However, in a swimming pool that has been in place for a period of time, the shotcrete may already be fully saturated.

Reinforcement Encapsulation

A few cores should be taken through the steel reinforcement, in order to verify the complete encapsulation of the reinforcement.  Hollow pockets from shaddowing and honeycombs are a common occurrences in inferior shotcrete.  

If improper contact lap splices were used when installing the reinforcement steel, then particular attention should be paid to these areas.  The large mass of bars frequently causes honeycombs behind these splices.

Cores containing reinforcement should not be relied upon to evaluate the in-situ strength of the concrete.

Test Results

ACI 318-08, Section, specifies two criteria that must be met for accepting the strength of in place concrete (fc' = specified strength of the concrete):
1) the average of any three consecutive strength tests equals or exceeds 85% of fc';
2) No individual strength test shall fall below 75% of fc'.

In other words, the average of THREE CONSECUTIVE tests must meet or exceed 85% of fc' AND the strength of every sample must be at least 75% of fc'.  

These lower acceptable margins are due to the inconsistent and unreliable development of concrete's strength in-situ.  In contrast, poured cylinders that are prepared as samples of the delivered concrete, are water cured under controlled conditions, and therefore expected to develop higher strengths (ACI 318-08, Section

Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: or 408-776-8220. 

Visit his website at: 
All Contents © Aquatic Technology Pool & Spa, 2013. 
No portions of this blog may be reproduced or re-posted without the expressed written consent of Aquatic Technology.

Friday, August 23, 2013

Pool Expert Witness analyzes aqua azul colored glass tile mosaic failure

Swimming Pool Construction Defect Expert Witness analyzes aqua azul colored glass tile mosaic installation failure.

Something for nothing? Never!

A homeowner in Los Angeles, CA got competitive bids to line his swimming pool with aqua azul colored glass tile mosaics.  The average price for ONLY THE INSTALLATION was $75 per square foot.  The cost of the tiles would be extra.

However, one company proposed to supply their own aqua azul colored glass tile mosaics and install them for around $20 per square foot.

Hmmm...  multiple companies provided bids that averaged $75 per square foot (labor and setting materials only) and this company was going to provide and install the tiles for only $20 per square foot?  

Remember, there is a sucker born every minute!  You don't get something for nothing!

Poor Quality Glass Tile Mosaics

Yes, there is a difference in the quality of glass.  Most cheap imported glass tile mosaics from Asia are formulated with recycled glass of unknown origin.  This bastardized blend results in many kinds of glass with different expansion indexes.  Under the slightest change in temperature (sunlight or heating a spa) and the different formulations of glass will expand at different rates.  And,  you guessed it, they will crack.

This company promoted their glass as being inexpensive because they cut out the middleman and imported container loads directly from Asia.  

Poor quality glass is poor quality glass, no matter where it's from.  The contractor did not care, nor were they even educated as to the science of glass.  

                      Click on the image to see the cracked aqua azul glass tile mosaics up close.

Deficient Installation Instructions

The Asian manufacturer of the aqua azul colored glass tile mosaics did not even supply installation instructions that complied with ANY published trade standard.  Their instructions did not recommend any compatible thinsets or grouts. They made no mention of the requirement for waterproof membranes.  No Tile Council of North America (TCNA) product analysis or testing were provided or available.

Their instructions said to merely mix by hand, a blend of white cement and sand.  They stated to set the tile directly onto the concrete pool shell.  No leveling mortar bed and no waterproof membrane was specified.

TOTAL Disregard of Industry Standards

The low ball contractor then merely followed the manufacturer's instructions, and set the tiles directly onto the concrete shell.  In some instances, they merely set the tiles on top of the old pool plaster.

No leveling bed or waterproof membrane was installed.  The tiles varied in appearance because of the variances in the underlying layer.  The tiles were not level and undulated across the walls and floor.  

                 Click on either image to enlarge them, so that you can view this abortion up close.

No movement joint was installed below the coping stones.  The gap that was supposed to be filled with a flexible material was instead filled with grout.  When the coping exerted stress upon the tiles from thermal expansion, the energy was transferred into the tiles.

                                                Click on an image to enlarge the cracks!
Whose to Blame?

Legally, the contractor is ultimately responsible for the poor quality aqua azul colored glass mosaic tiles and the inferior workmanship.  There is absolutely NO EXCUSE for ignoring the published trade standards regarding the proper installation of glass tile mosaics in a swimming pool.  

A waterproof membrane is a "no brainer."  They are required in shower pans and showers are only wet for a few minutes at a time.  Swimming pools are full of water 24/7 and 365 days a year!

The property owner is to blame as well.

They were simply GREEDY and CHEAP.  They wanted something for nothing.  They wanted the look of the expensive glass tile mosaics without the associated price of doing it correctly.  


The property owner did not do their due diligence.  The search engine GOOGLE would have revealed that the contractor left Arizona, when their contractors license was REVOKED by the State of Arizona.  At the time, the State of California Contractor's Licensing Board records showed disciplinary actions and sanctions.  On-line reviews of the firm indicated that they were unscrupulous.

Yet the property owner hired them any way.  What a deal!  What an idiot!

                                   Click on the image to enlarge the delaminating tiles.

Instead they ended up with a nightmare.  But, they really got what they deserved.  This contractor and this property owner were made for each other.

Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: or 408-776-8220. 
Visit his website at: 

All Contents © Aquatic Technology Pool & Spa, 2013. 
No portions of this blog may be reproduced or re-posted without the expressed written consent of Aquatic Technology.

Expert Witness, Watershape Consulting & Swimming Pool Construction

How to contact us

We frequently receive inquiries through this blog's comment form, seeking construction advice or designer/builder referrals.  We cannot respond to comments made through the blog, as we are not provided with your contact information.

Please use the email address posted in the footer for inquiries, permission to re-post the contents of this blog or for hiring Paolo Benedetti for swimming pool design, construction or expert witness work.

Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: or 408-776-8220. 
Or visit his website at:

All Contents © Aquatic Technology Pool & Spa, 2013. 
No portions of this blog may be reproduced or re-posted without the expressed written consent of Aquatic Technology.

Thursday, August 22, 2013

Swimming Pool Expert Witness - What to expect

What to expect when hiring a Swimming Pool Expert Witness for Litigation - You're going to Court.

When an attorney hires the expert

Sometimes, a law firm retains the services of an expert witness.  This is a strategic move that is exercised when the case involves a lot of unknowns.  If there exists uncertainty as to the validity of a claim or if the expert may reveal liability on the part of the client, this is usually a smart move.

By having a law firm hire the expert witness directly, anything generated by the expert witness becomes the "work product of the attorney" and is usually not subject to discovery.  

A word of caution.  In this instance, a smart opposing attorney will know that not every work product of the expert witness was disclosed.  They will spend a lot of time and effort, questioning the experts findings, opinions and conclusions.  The expert must answer these probing questions under oath.  Items that were not disclosed may be revealed anyway.

Truly Objective Experts

Sometimes the client's case cannot be supported by the expert witness's analysis.  The expert witness must "tell it like it is," regardless if the outcome is positive.  Do not expect an expert witness to lie or twist the truth, merely because you are paying the bills.  

Expect the cards to fall where they may.  This is another reason why having a law firm hire the experts may be a good idea.  Information detrimental to the client's case would not have to be revealed.

Expert Witness Referral Firm

Do you really need the services of an expert witness referral firm?  Probably not.  Some of these firms maintain control of the invoicing for the expert witness's services.  They add a surcharge to the expert's invoices before forwarding their own invoice for payment.  If your attorney has hired the expert witness, expect the law firm to also add a mark-up to the invoice.  Padding on top of padding!

Other referral services charge the expert witness a "finders fee" for each case referral.  The expert is going to recover this fee somehow - either through inflated fees, surcharges, overhead or other hidden expense.

With the advent of internet search engines, it is very easy to locate, research the background of and directly hire your own expert witness.  After all, isn't that how you found this blog?

Open Book or Case Initiation Fee

Most expert witnesses charge an "open book" or "case initiation" fee.  This fee is the cost to hire and lock-up the expert as your expert, so that the opposing party cannot hire them.  Some smart law firms hire every decent expert witness that is available, merely to prevent the opposing party from hiring them.  After receipt of this payment, the expert witness is said to have been retained.

This also gives you the right to name those experts as your experts, whether you intend on using their services or not.  Sometimes, cases settle just because one side has retained the best experts available.

This fee is not applied to any work product.  It is only for the right to name that expert as yours.


Expect a contract that requires a retainer (deposit) against which work is invoiced.  Just like an attorney, an expert witness bills by the hour for everything that they do for your case.

The worst cases drag on for years, and the expert is entitled to be paid as their work progresses.  Periodically recharging a retainer and billing against that deposit, ensures that the expert is paid promptly.

Case Materials

The expert is required to read every document that is provided to them.  Oftentimes, many duplicates of the same documents are submitted from different sources.  

Duplicate documents must still be reviewed to ensure that they are exactly the same.  Everything must be cataloged and archived for later retrieval.  Binders of materials are assembled and tabbed as to their origin or source.  Digital photographs must be printed and assembled into an album.

Project Evaluation

The expert may require the support of other specialized experts to determine if standards and specifications were adhered to.  These experts will be an additional charge.

Such specialized experts may include a material testing laboratory, forensic materials scientist, soils engineer or geologist or structural engineer.  These specialists can assist in determining if various aspects of the project were sufficient for their designed purpose.

Standby and Reimbursables

The time the expert spends on your case, is time that they cannot bill another client or project.  This is called "opportunity cost."  The expert has lost the opportunity to sell that time or resources to another client.  Time spent traveling to and from site inspections, airline flights and time spent sitting in court rooms waiting are examples of lost opportunities.  The expert cannot be working on other projects - it is unrecoverable time.

"Standby time" is when the expert is required to be available for depositions, court hearings or teleconferences on a moments notice.  This usually requires that they remain near a phone and be committed to having a minimum response time.  Since they cannot go about their normal course of business unfettered and without restriction, there is usually an hourly fee associated with "being on stand-by."  You have consumed their ability to focus 100% on another project.  Because the expert can do "busy work" while on standby, standby time is usually billed at a reduced hourly rate.  While not common, standby time does occur on occasion.

Expect to be charged for overhead, administrative and reimbursable expenses.  Airline tickets, hotels, meals, duplication expenses, overnight shipping, photo printing, CD/DVD duplication and CAD drafting are all examples of reimbursable expenses.  Vehicle mileage is another example of a reimbursable overhead.

Administrative support, which is billed at a lower hourly rate than the expert doing it themselves, is an economical method of completing work for the client. 

Contact the author, Paolo Benedetti of Aquatic Technology Pool and Spa at: or 408-776-8220. 
Visit his website at: 
All Contents © Aquatic Technology Pool & Spa, 2013. 
No portions of this blog may be reproduced or re-posted without the expressed written consent of Aquatic Technology.