Thursday, November 10, 2011
Glass Tile Mosaic Pools, Spas & Waterfeatures - ONLY Use Quality Glass Mosaics
Cheap is not Good
When it comes to glass tile mosaics, there is no such thing as an inexpensive high quality tile. I have inspected over 40 projects that had some type of glass failure. I am personally aware of at least another 50 - people who, for whatever reason, chose not to hire me to evaluate their issue(s). They were kind enough to forward pictures, samples and installation images.
In every case, the defects were attributable to a combination of poor quality glass tiles. If questionable installation practices were employed, the problems only compounded themselves.
Glass tile mosaics from the home improvement warehouse stores, internet, close-outs or cut-rate tile contractors that sell for under $10 per square foot, are almost always to blame. A recent $20+ million dollar estate that I visited, had thousands of square feet of $2 per square foot glass tiles installed. Where's the mentality in that?
Internet
There are literally thousands of companies on the internet hawking glass tile mosaics. "Quality glass tile $4.99 / sq ft" reads a leading search results. Of course they're not going to say, "Cheap prices, Cheaper Quality Glass Tiles from $4.99 / sq ft," but they should!
Some of these vendors are actual manufacturers, while others are merely middlemen or distributors. Most people look at samples, and because it looks like a name brand tile, they automatically assumes that it is of the same quality. This assumption could not be further from the truth!
While we'd all love to have our surrounding done in the most lavish materials possible, the simple fact is that quality glass tile and it's proper installation is EXPENSIVE - VERY EXPENSIVE! I'm in the trades, and I don't even have a swimming pool lined in glass tile (though my spa is!).
Quality glass tile mosaics start around $15 per square foot and go upwards from there! A simple blend of Italian glass tiles mosaics can easily cost $20-40 per square foot. And, these blends are their standard blends, ones that they do routinely, already have the graphics computed and maintain in inventory.
Select a custom blend of tiles from their color palette and the cost can run $40-60 per square foot, depending on the colors & complexity of the blend. Choose ORO (24K gold leaf sandwiched between layers of glass) and the cost rises exponentially - upwards of $750 per square foot (depending on the current market price of gold).
Inferior Manufacturing Procedures
I've previously discussed the methods used by various glass tile manufacturers employ to reduce their production costs: firing temperatures, annealing, blending, raw materials, recycled materials, double firings and contaminates. So, I'm not going to discuss those again here.
Besides the shortcuts employed during the actual making of the glass, there are other means of reducing their costs. The lack of initial quality control, ongoing random quality control inspections & testing and the tracking production lots are the most prevalent. Many do not even possess testing facilities or employ outside laboratories.
Color
There are a couple of methods of coloring glass tiles. The most common is the use of chemicals and oxides to actually change the color of the glass. Because the color is throughout the material, any chip or scratch will not change the perceived coloration. This is the oldest and most proven method of coloring glass and dates back to before the ancient Romans. The leaders in this field are Lightstreams, Bisazza and Sicis (Lightstreamsglasstile.com, Bisazza.com, Sicis.it).
Applying a colored coating to the reverse of a layer of clear glass is the second most common method of coloring tiles. The best method of achieving this is to actually melt 2 layers of glass together, a clear layer atop a colored layer. The colored layer does not need to be thick. These tiles have a very contemporary look and a great sense of depth, as there is a layer of clear glass on top of the actual color. The layer of clear glass can vary in thickness, depending on the manufacturer. However, the thicker the tile, the greater the potential that each tile will contain inherent stress, that will cause the tile to crack in the future.
Another method of back coloring clear tiles is to melt a coating onto the glass. There are a few companies that have refined this process and manufacture a high quality product. Interstyle (interstyle.ca) of Canada is one such company.
But, there are a lot of knock-offs that try to emulate the appearance of these products from these quality manufacturers. The most common is the of recycled glass and the lack of quality control Refer to my prior articles about the dangers of utilizing recycled glass - while it is "green" it poses a serious financial risk to the installer & purchaser!
An attempt to back color clear glass has been attempted through the use of hand painted, silk screened, or sprayed on paint type of coatings. Anyone with a brain can surmise out that these coatings are not going to stay bonded to the smooth glass surface for long.
Another inferior process is a glued on backing. Because none of these companies ever bothered to perform accelerated failure testing of their materials, they have no idea if the backing will stay attached to the glass tile. Many don't even know if the adhesives they use are even waterproof! Place these tiles into a submerged application such as a swimming pool and in a few years you'll have a delaminated mess. Sometimes the colored backing itself is water soluble. Okay for a back splash, but in a shower, bathtub, fountain, swimming pool or spa you quickly have tiles popping off or letting loose - sometimes in big sheets.
(Color backing on the left has separated, darker ones on right are still bonded. Dark thinset highlighted mesh backing.)
Spacing Mesh (aka: mesh backing)
Oftentimes as the backing begin to fail, the mesh backing on the tiles starts to become visible. This is most evident on clear or translucent tiles, since you can actually see through the entire tile. This exactly why quality manufacturers of clear or translucent tiles do not use mesh backings - they can show through the tiles - even without any type of failure.
The mesh backings are merely designed to maintain the spacing between the tiles during installation. They are not designed to adhere the tiles to the substrate. But a poor quality backing can cause bonding issues. Backings that are too large, do not allow for the 90% contact with the thinset that is required by the standards. Plastic dot backings are the worst of these offenders.
(Mesh covers a large percentage of surface, improper use of dark thinset highlights the mesh. Note: poor alignment of the grout lines).
Personally, I prefer paper faced or plastic film faced tiles. Once set into place, the facing paper of plastic film is removed - there is absolutely nothing to interfere with the tile's contact with the thinset. Over the years, I have seen countless ceramic, stone and glass tiles delaminating from projects because the mesh backing was glued on with a soluble glue. As the glue dissolves and releases, it also causes the thinset to lose it's bond - and the tiles begin to fall off.
The Solution ? Replace the Tiles
Chipping glass tiles from a swimming pool shell is one of the messiest and potentially dangerous jobs in our industry. Shards of glass fly everywhere. Though protective gear is worn, vacuums and pressure washers are employed, small invisible shards seem to spread everywhere. Inevitably barefoot people seem to locate every glass shard around the pool for months following a projects reconstruction.
Installation Costs
Proper preparation, waterproofing and installation for a swimming pool is presently running around $80 per square foot (retail). Contractors who do the installation themselves with trained crews can expect their labor and material costs to be around $55-60 per square foot.
If the project has a lot of details that require a lot of trimming of tiles around jets, fittings, stairs, or circular vessels (e.g. round spas or fountains), then expect to pay on upwards of $100-125 per square foot. Meticulous details take time. And time is money!
You should expect and receive quality... compare some installations below. You can easily spot the quality VS the hacks!
( Click on an image to enlarge it)
YOU ONLY PAY ONCE FOR QUALITY!
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Wednesday, November 9, 2011
Infinity Edge, Vanishing Edge, Negative Edge Pool Design Issues
Sounds Simple Enough?
In every one of these pools there is a "dam wall." That is a wall that is supposed to be dry on one side & wet on the other - imagine the reservoir where you go water skiing. Some of these pools dam walls are 6-8 feet high, while others have low dam walls of only 4-8 inches high.
The other common element is that there is a catch basin for the water. Some have the basin attached to the pool, while others transport the water to a remote storage vessel. The remote vessels can be under the pool equipment room, adjacent to the pool, under the pool deck, a lawn or any place in between. There just needs to be access to the inside of the tank, so that the accumulated debris can be removed. I'll use the terms: storage tank, surge tank & catch basin interchangeably.
Common Problems
The most common problem that I see when consulting on construction defect cases, are surge tanks that are too small. There must be enough water in storage to (a) fill the pipes, (b) raise the level of the main pool so that it over flows, (c) complete the trip to the storage tank. Remotely located tanks usually have gravity lines from the pool to the tank, so this is the "trip back to the tank" (as in c). All totaled this is called the "water in transit."
There must also be a "reserve" of water left in the bottom of the tank to prevent the drains from vortexing (swirling) and ingesting air. This can cause the pump to lose prime, eventually damaging the pump seals & bearing and allow water to enter the motor.
The second most observed problem is the edge effects system (drains, pipes, pump & filter). Usually there are not enough drains of a design that will allow debris to pass through. Instead leaves accumulate on top, restricting the flow starving the pumps for water. The plumbing is usually undersized for the line velocity of the water (feet per minute). The pump is usually WAY TOO BIG to flood the edge. And there is usually no filter on the edge pump. 95+% of the debris in one of these pools ends up in the storage tank. So, why in the world would you want to grind up the leaves, earthworms, salamanders and snails & spit them back into the pool?
Improper placement of the return lines can cause unwanted surface turbulence, destroying the glassy mirror effect that these pools are know for. The primary causes are due to high flow rates, placement in the walls, incorrect elevations and poor aiming of the return flow. There are very simple techniques to guarantee that turbulence will not be a problem, but you have to have this knowledge & employ the solutions during construction!
The next most common issue is with the dam walls themselves. Oftentimes incorrect construction techniques result in a wall with voids, allowing water to seep through. Poor waterproofing techniques can result in tiles that weep. Inadequate expansion joints in the material on the "dry" side of the wall can cause the material to delaminate. After all, isn't this material constantly going through wet & dry, hot & cold, and expansion & contraction cycles? They are after all usually exposed to the direct sun & wind.
Other fatal mistakes are the discharge of excess water and backflow prevention. Rainwater simply cannot be dumped on the slope below the pool - a foolish mistake. One that will surely cause a landslide or in the least cause the pool to slip or tilt. One cannot simply rely on mechanical check valves to prevent water from back siphoning to the equipment pad or catch basin. Check valves flutter and the seals get worn or tear. Face the facts - not if, but when it fails... One needs to rely on physics - something like gravity that is never turned off!
The "Goal"
The goal with one of these pools is to create the flooding effect with the least amount of water in transit as possible. A vanishing edge pool with an exposed catch basin IS NOT SUPPOSED TO FUNCTION AS A WATERFALL. That will cost you many more pumps and a W-I-D-E basin to catch the splash & splatter. The back side of the wall is supposed to appear as a "glistening wet wall."
If the edge tolerances are maintained (how level the finish workmanship is), then you will be rewarded with a pool that can be flooded with the smallest pump. If the pool is "dead on level" you could create the effect with a garden hose! Granted, you would need a larger pump to return the water to the pool displaced by bathers, but this is where a VFD (variable frequency drive) pump could come in really handy. It could run at low speeds to provide the normal visual effect. When bathers are present, it could ramp up the flowrate to meet the need of returning the bather displacement to the main pool.
These pools are spectacular to look at. While on the surface they appear simple, they are actually quite complex.
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Tuesday, November 8, 2011
Caribbean Resort Knife Vanishing Edge Pools
2010 - Beach front construction on driven concrete piles.
Completed project - knife edges, 2 beach entries, and a vanishing edge.
Glass tile mosaic waterfall between the second and third tier pools.
Glass tile mosaic grotto and waterfall.
Close up of the glass tile grotto and waterfall.
Project Credits:
Location: British Virgin Islands - Virgin Gorda
Architects: Roger Downing & Partner Co. Ltd.
Developer/Contractor: Victor International
Swimming Pools: Paolo Benedetti - Aquatic Technology
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Glass Tile Mosaic Infinity Edge Pool Design
Project Credits:
Architecture: Swat/Meirs
Construction: Silver Creek Development
Vanishing Edge Pool: Paolo Benedetti
Glass Tile: Sicis - Custom Blend
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Monday, November 7, 2011
Glass Tile Mosaic Infinity Edge Pools
It all about the glass!
Since a glass tile mosaic pools can consume a thousand plus square feet of material, everyone & his uncle are promoting their glass tile as suitable for swimming pools. They'll sell more tile for one pool, than they'll sell for showers and back splashes in an entire year.
But be forewarned, YOU GET WHAT YOU PAY FOR!
The cheap glass mosaics that you find at your local warehouse store are not suitable for outdoor applications, let alone swimming pools. Even worse, are the thousands of cheap Asian imports that are flooding the market.
Tile distributors and vendors in the United States, seeing the opportunity to make some money, have entered into private labeling agreements with these inferior Asian manufacturers. Some reputable furnishing companies have also put their names on some of these inferior tiles.
Almost no one from these United States companies has even bothered to travel to Asia to visit or inspect the manufacturing facilities. They have absolutely no idea how the tiles are made, the ingredients, whether the correct manufacturing procedures are being followed and the if there are even any quality control measures.
Limited Liability
In California for instance, a retailer is not liable if a product they sell is later found to be defective. That liability falls on the manufacturer.... do you see where this is going? The importer and retailer are free and clear!
You're going to have to sue the manufacturer in Asia to recover your losses when the tiles begin to fracture, crack, spall or disintegrate.
While you can sue the entities in the United States, they will claim that they have no control over the manufacturing process - hey, maybe that's why they don't want to go inspect the manufacturing facilities??? You think??
Poor Installation Practices
To top off the inferior tile, these Asian manufacturers are including installation instructions that do not meet international standard for glass tile installation (e.g. ISO, ANSI, TCNA, CTCA).
I was recently provided a set of instructions by a contractor in California, who insisted that the instructions included with the Chinese glass tile that he was selling were adequate. The Chinese instructions did not specify a leveling bed or waterproof membrane, nor did they even provide a list of tested and approved setting manufacturers. Their instructions said to mix "readily available white cement & sand" into a slurry paste to seal the concrete shell. A second coat of the same slurry was to be used to adhere the tiles to the pool shell. Finally, they stated that "any commercially available grout" could be used to grout the tiles.
Worse yet, the contractor ACTUALLY BELIEVED that this was adequate. And the homeowners and property owners he sold directly to bought into his horse & pony show.
If the going rate for the installation alone of glass tile is $55-$100 per square foot, then how can he provide and install glass tile for $20 per square foot?
Cheap inferior materials and inferior installation practices!!! Just follow the contractor's trail of unhappy customers and license revocations in other states!
I'd love to drive a Ferrari and only pay the price of a Yugo - but seriously, it isn't going to happen! Don't let your greed get the better of you!
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Vanishing edge, infinity edge, negative edge, knife edge swimming pool
A picture is worth a thousand words:
Design & Construction Consulting by Paolo Benedetti
Built by Paradise Pools
Paolo Benedetti
Aquatic Artist"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Thursday, October 27, 2011
Independent Inspections & Testing Laboratories
Standards & Specifications
Every project must have some minimum level of standards and specifications. Usually the minimums are established by the building codes, building department or the inspecting government agency. These may include soils reports, structural engineering, civil engineering & grading or erosion control plans.
The property owners may chose to have even more detailed plans prepared that illustrate construction details, hydraulic and plumbing system design, vessel and landscape lighting, high and low voltage electrical schematics, equipment specifications, finish materials, and the standards and specifications by which all of this is to be installed.
In the absence of detailed specifications, the owners are apt to receive the bare minimum in quality that the contractor or his sub-trades can get by with. But oftentimes, these bare minimums do not comply the published industry standards and acceptable trade practices.
The adopted building codes in every region may not specify or dictate the installation standards for every detail of a project. However, there are a myriad of other accepted standards that step in to fill the voids. These may be published industry standards, acceptable trade practices or even codes that are referenced (and thereby included) in a regions approved building codes.
Building Inspectors
Government building inspectors are generalists by their very nature. They must know a little about a lot of various construction codes & standards. Their primary purpose is to ensure the safety of the construction. An individual inspector may excel in a particular field, due to prior experiences.
In some large regions, the government building inspectors are specialists. An inspector may only inspect one aspect of construction projects, whether it be foundations, plumbing, electrical, framing & structural, etc.
Rarely are they concerned about workmanship. Provided that a detail is not unsafe or installed in violation of a code or statute, they will not concern themselves with the methodology, materials or the final "fit and finish."
Who should do the quality control inspections?
So how does a property owner ensure that they receive what they are paying for, that the installations are done correctly and the materials are not substandard?
The first step is to ensure that the project is completely specified prior to the bidding process. This ensures that the contractors and sub-trades are notified of the level of workmanship, installation practices, assembly materials and the quality standards that are expected of them.
The second step is to hire individuals to enforce compliance with the project specifications. Rarely can this can be performed by the developer, general contractor or swimming pool contractor, as most do not have the requisite continuing education, training or intimate knowledge of the myriad of applicable trade standards. Therefore, the owner must employ specialists to inspect the various stages of construction.
Some of these inspections are performed by members of the original project design team. A soils engineer should inspect the completed excavation to ensure that the exposed conditions are no worse than those predicted by their exploratory drilling. The structural engineer should inspect the installed reinforcing steel, to ensure that it has been installed as per their engineering plans. A project architect may chose to perform the inspections on the portions of the project that they designed.
Deputy/Special Inspectors
Many building departments have come to realize that their inspectors cannot possibly remain on site during the gunite, shotcrete or concrete placement. Nor do they possess the testing facilities to sample and test the materials to ensure their compliance with the specifications outlined in the structural engineering. Therefore, many building departments require Deputy or Special Inspectors perform these services. These inspectors are sworn or licensed by a government agency to inspect, observe, sample, report and issue "correction notices."
Their services are usually retained to double check & inspect the reinforcing steel - ensure that it is of the correct size & strength, placed in the correct patterns & spacing, blocked correctly and that the proper clearances were established. They may even take a sample of the steel to a laboratory for testing.
Deputy Inspectors are also utilized to observe the placement of the concrete. They are the "eyes and ears" of the building department. They ensure that incompetent materials such as trimmings, rebound & blow-back are not merely shoveled into the structure. They ensure that a blow pipe is constantly utilized to expel loose material. They will ensure that poured in place concrete is placed correctly & consolidated.
They will also obtain random samples of the concrete throughout the day, to ensure that the concrete is of the mix design and strength. These samples are later cured and tested to ensure that the concrete develops the proper compressive strengths.
Their use in swimming pool construction is usually limited to inspecting the reinforcing steel and observing the concrete placement. However, there are deputy inspectors available to inspect all aspects of any type of construction project.
Independent Inspectors/Consultants/Owner's Agent
Since building inspectors and deputy inspectors are not concerned with the installation practices employed, property owners must have another avenue to ensure that other aspects of a project are being installed correctly.
Independent inspectors or consultants who specialize in swimming pool construction can be hired to perform periodic inspections as construction progresses. Their intimate knowledge of the various standards that govern the sub-trades, will ensure that a project is installed to the acceptable trade standards and practices.
For instance, a building inspector merely checks the plumbing manifold to ensure that it is under pressure. But an independent inspector will inspect the plumbing to ensure that it is of the correct size and diameter, that it is routed and connected correctly, and that provisions for the prevention of back flow & back siphoning are in place.
These consultants can review the installation practices with the sub-contractors, to ensure that they are aware of the standards to which they will be held. Though they may not be a part of the building codes, these various trade standards have become the acceptable methods of performing various trades. In a civil court, these are the standards to which a tradesman will be expected to perform.
On some large projects, the property owner will employ an "Owner's Agent." This person is usually a person with a construction management or engineering background. Their sole purpose it to inspect and approve the construction workmanship of the general contractor, swimming pool contractor, and sub-contractors. Sometimes they have the authority to act on the owner's behalf in making design or project modification decisions and to authorize change orders.
Pay me now... or Pay me a lot more later!
Litigating construction defects means the expense of an attorney, lost work time, cost of experts and testing labs to analyze deficiencies, the inconvenience of repairing the errors, additional expenses to modify a design, living with the deficiencies during the litigation, mental and physical stress, and sometimes the necessity to completely demolish a project and start construction anew. Remedial repairs often entail re-engineering or re-designing portions of a project, resulting in design concessions, further delays & expenses. The finished project "will never be quite like it should have been."
It is always more economical to employ your own inspectors during a project, than it is to litigate and repair construction defects after a project is completed.
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Wednesday, October 19, 2011
Indoor Pools - Dehumidification is a must!
Moisture
Moisture in the air (humidity) is the biggest obstacle to overcome when designing or building an indoor pool. Failing to address the evacuation of the humidity can have devastating structural, safety and health repercussions.
Dehumidification
Dehumidifiers are expensive, to both install and to operate. They are the ONLY proven means to remove the moisture from the air. Since there are a lot of variables that go into specifying and sizing the correct unit, an expert in this field should be employed. Most of the dehumidifier manufacturers have mechanical engineers on staff who can assist your local mechanical contractor in selecting the proper unit, ducting, and make-up air.
Do not think that you can "brain storm" your way out of buying one of these expensive units. Swimming pool & mechanical contractors have been wrestling with this issue longer than you've been alive. Your hair-brained boot-strap cheapskate methods and ideas of an opening ceiling, sliding walls, lots of windows, air temperature matching the pool temperature, etc. have all been attempted by someone before you. AND THEY FAILED!
An automatic pool cover is the only PARTIALLY "saving grace." An automatic pool cover will reduce the humidity in the room. NOTICE THAT I SAID REDUCE AND NOT ELIMINATE! The installation of an automatic pool cover will only allow for the downsizing of the dehumidifier.
I'm not going to waste time validating why these other "economic solutions" are not sufficient or don't work. You'll have to take decades of experience as the gospel truth. You are not going to come up with any new ideas that haven't already been tried. We've already "been there - done that."
Too much humidity - BAD DOG!! MUY MALO!!
Humidity is formed in the air from the evaporation and splashing that occurs indoors. Mother nature always seeks a balance - think of it as karma, ying-yang, etc.
Humidity in the air can lead to the growth of black mold in the walls of the structure, light fixtures, window & wall coverings, drywall or other surfaces. Breathing the spores of black mold has been linked to respiratory infections, pneumonia and even deaths.
Humidity in the air can also foster bacteria growth. These bacteria once inhaled can also result in respiratory infections. A common ailment is "lifeguard lung," frequently seen amongst indoor lifeguards.
Humidity in the air can also lead to corrosion of structural members of the building. Because we're talking about a vapor (think "gas"), it can permeate & enter walls, ceilings & floors. Corrosive structural elements (steel brackets, i-beams, fasteners, etc.) are all subject to corroding that's occurring inside the walls were you cannot see the damage!
Humidity can also corrode the wiring in the walls, receptacles, switches, light fixtures, or anything else metal within the building. I needn't tell you the dangers of corroded electrical wiring & fixtures. ZAP-OUCH! RUN-FIRE!
Condensation
Humidity in the air can also lead to condensation inside of the walls, on glass windows, tile surfaces, painted walls and skylights. These water droplets form when the surface temperature is below the dew point in the room. It is practically impossible to heat the glass, painted walls, floors, steel I-beams in the walls, tiled walls, etc. in order to keep them warmer than the air within the room.
In regions of the country where the winters are harsh, you are guaranteed to have condensation UNLESS the air is dehumidified! If the moisture content in the indoor air is low, less water vapor will condensate upon these cooler surfaces.
Condensation will also "pool together" and form run-off. This dripping water can lead to it's own series of destructive forces on your structure. Think about standing inside of your bedroom and misting the room with a garden hose. Do this every day, 24/7. Do you think that you'd start to experience negative effects to the room, walls, floors & it's furnishings?
If you are dead set on having an indoor swimming pool or spa, then you absolutely MUST install and operate a properly sized dehumidifier. A unit that activates automatically is the wisest choice!
Don't think that you're wiser than everyone who came before you. There is no cheap way out.
There are only TWO CHOICES HERE - an outdoor pool or a dehumidifier!
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Friday, August 5, 2011
There's NO such thing as WATERPROOF CONCRETE - or is there?
Lately there has been a lot of misinformation provided about "watertight" or "waterproof" concrete. This misinformation is the result of people confusing the two terms PERMEABILITY and WATERPROOF.
Let's first outline some basic scientific facts (per the American Concrete Institute - ACI):
1. CONCRETE IS PERMEABLE (ACI),
THEREFORE,
2. CONCRETE CANNOT BE WATERPROOF
(without taking additional measures such as special admixes or surface coatings - ACI).
3. THE DENSITY OF THE PLACED CONCRETE AND (the original) WATER CONTENT OF THE MIX DESIGN - ONLY AFFECT IT'S PERMEABILITY.
False Claims? or Just Confused?
To claim that a dense concrete vessel is watertight or waterproof is a scientifically false statement. It may in fact have a low permeability (the ability of the water to pass through the concrete), but it will still have some measurable level of permeability. You may be able to fill it, and it might not appear to lose any water, but it is still permeable - and therefore losing some water. The mere fact that water can pass into the concrete, illustrates that it cannot be WATERTIGHT or WATERPROOF. It is physically impossible (without the assistance of admixes), regardless how dense the concrete is.
The higher the level of hydrostatic pressures upon the surface of the concrete, the greater the distance the water will permeate the concrete. Given concrete of the same density (PSI,MPA) and therefore the same level of permeability, here is an example of how permeability can affect "water tightness" of a concrete structure:
a. Under water at the upper elevations of a large concrete dam, there is barely any hydrostatic pressure upon the surface of the concrete. The water will penetrate and saturate the concrete only to a certain depth.
b. At the base of the dam, where there exists extreme levels of hydrostatic pressure, the water will penetrate a greater distance into the concrete wall. This occurs even when the concrete has the same density as the upper elevations.
In the case of the Hoover dam, water is actually seeping through the concrete walls at the lower elevations! This is because ALL concrete is permeable. The hydrostatic pressure is actually driving the water through the permeable matrix of the concrete.
Increase the Density
Increasing the density of the concrete can only reduce the permeability of the concrete, but it cannot eliminate it. Microscopically, there are a multitude of passages through the concrete. There are small cracks around the aggregates. There are small fissures in the concrete from the shrinking that occurs during it's curing stage. There are voids where the water in the original mix once was.
Methods to increase the density of concrete, and thereby reduce it's permeability are achieved by:
1. reducing the water in the original mix (utilize super-plasticizers)
2. increasing the "fines" in the original mix (silica fume particles are 100 times finer than cement particles)
3. practicing approved curing methods
4. proper placement and compaction of the wet concrete
5. employing specialty "waterproof" (densifying) admixes
Silica Fume
Because of their small size in relation to cement particles, the silica fume particles can fill in tiny voids that occur between the cement & aggregate particles. The silica fume particles will react with the free lime that is released during cement hydration. The end products are calcium silicate hydrates (CSH). These CSH particles replace the weaker lime that is normally found in concrete. In field use of silica fume as a component of a mix design will reduce permeability by 20 times, over a mix design without silica fume.
"Waterproof" Admixes
The use of "waterproof" admixes (e.g. Xypex, Kryton, etc.) merely make the concrete so dense, that it becomes for all intensive purposes, impermeable. The shell is technically waterproof, because the concrete is impermeable. The presence of water with these admixes, actually promote additional crystalline growth - sealing the permeable microscopic voids, a term called "hydroscopic self-healing." Mind you, this is occurring on a microscopic level, so these crystalline structures will not heal structural or shrinkage cracks. However, poorly placed, improperly cured, or too much water in the concrete will defeat any benefits of these admixes.
Untreated 1. CONCRETE (UNTREATED) A control sample of concrete was sheared through at 50 mm below the top surface. The sheared face shows some of the by-products of cement hydration with which Xypex reacts. Precipitated calcium hydroxide together with cubic and rhombic particles are visible. (courtesy of www.Xypex.com)
Initiation 2. XYPEX CRYSTALLIZATION (INITIATION) Taken at 50 mm within a Xypex-treated concrete sample, this photograph shows the initiation of the Xypex crystalline reaction after Xypex Concentrate was applied to the surface. (courtesy of www.Xypex.com)
Mature 3. XYPEX CRYSTALLIZATION (MATURE) This photo was taken 26 days after the application of Xypex Concentrate at a depth of 50 mm into the concrete sample. A dense, fully developed crystalline structure has formed within the capillary tracts of the concrete to completely block the flow of water. (courtesy of www.Xypex.com)
Permeability Testing
The problem with the widely utilized Rapid Chloride Permeability Test, is that it does not measure the depth of the chloride penetration or how rapidly the chloride ions reached a specific depth. An accurate measurement of permeability must be able to measure BOTH the depth and rate of penetration.
Alternate tests that provide these measurements do not take into account any atmospheric or environmental conditions that may increase the penetration (hydrostatic pressure), as these tests were created by highway departments to measure the quality of in-place concrete. The surface of a concrete slab, overpass, or guard railing has virtually ZERO hydrostatic pressure upon it.... only the thickness of the rainfall!
Because ALL concrete is permeable to some degree, we should all be striving to achieve maximum density in our placed concretes. This lessens the permeability and the chances of reinforcement corrosion - but, it does not eliminate the risk.
Waterproofing / Watertight
The ONLY means to create a WATERPROOF or WATERTIGHT vessel, is to eliminate permeability - which by concrete's nature is scientifically impossible. If you are willing to forgo additional waterproofing measures, then you are also accepting an unknown level of permeability into your concrete structures. The level of permeability may be minuscule, but it is an UNKNOWN that I am not willing to accept.
To actually claim that a vessel is WATERPROOF or WATERTIGHT, without the additional use of waterproof barriers is false. The concrete is still permeable, maybe it is less permeable than vessels built by others, but it is not water proof or watertight! The only means to achieve a waterproof or watertight vessel is to 100% eliminate the permeability.
The only way to stop the permeability, is to keep the water away from the concrete. This is where waterproofing measures come into play. Curing sprays do not make a vessel waterproof - they only help reduce the permeability, so do not buy into the "waterproof" sales pitch.
Because waterproofing cannot be applied to the reverse of a concrete vessel shot against earth, it is imperative that proper placement, compaction, mix design and curing procedures be followed. The addition of waterproofing admixes will reduce the permeability of the concrete from the reverse side, protecting the reinforcing steel and thereby increasing the structure's lifespan.
Be sure that you use the correct terms:
INCREASED DENSITY REDUCES PERMEABILITY AND INCREASES DURABILITY (but it is not waterproof).
WATERPROOF MEANS THAT WATER CANNOT / DOES NOT ENTER (i.e. PERMEATE) THE CONCRETE.
(Scanning electron microscope images & descriptions used with permissions and courtesy of www.Xypex.com)
Paolo Benedetti - Aquatic Artist"Creating water as art."™Aquatic Technology Pool & Spa©www.aquatictechnology.com
Wednesday, June 15, 2011
Bidding Ethics - The big question from Pebble Beach, Napa, San Francisco, Marin Pool Designer & Builder Paolo Benedetti
"Bidding"
Bidding against other contractors for an opportunity to construct a project is all well and good, if the project's specifications are well defined. This works great for government & public works jobs, because they have a clearly defined set of standards.
Because most pool contractors do not build to the "highest standards of workmanship and detail" the property owner is left to sort through the myriad of differing quotes.
Cost vs Quality
Low cost and quality are opposing forces. You get what you pay for! Enough said.
Comparing Proposals
Circulating a simple "plan layout" of a pool project without specifications or details is asking for trouble. Many contractors do not possess the "skill set" (experience or education) to identify potential problems with a project at this stage.
Bidders are told "bid it like it was presented" "It's a design-build, so go ahead and specify what you'll do differently."
Great, now they want their job specified for free, too!
If all of the pool builders could all see the forest from the trees....
Hidden Costs with "Design-Build"
"Design-Build"
What this really means to a potential bidder is:
"Bid the project based on the minimal information that was provided. Get the contract with a low bid and minimal everything. Once items begin to be defined, point out what was included and then hit them with the change orders."
So, you offered the project to one of the lower bidders. Once they obtained the soils report, they come to you with a change order. The pool requires special engineering. "Cha-ching."
The engineering says that it has to be built stronger and with special foundations, that were not provided for in their "basic contract." "Cha-ching."
They determine that the surge tank on the vanishing edge pool was designed too small. "Cha-ching."
The plumbing exceedes the minimum sized plumbing and quantity that their "basic contract" allowed. "Cha-ching."
The raised walls that will hold back water will require waterproofing inside and out. "Cha-ching."
Your final selection of finish materials will require additional labor and special installation methods. "Cha-ching."
The walls were build too high to allow for the thick stone that you chose. The walls will have to be chipped down (never mind that they will now be too close to the reinforcing steel). "Cha-ching."
Extra pumps and filters will be required for the vanishing edge, spa jets and water features. "Cha-ching."
The general Contractor on your job isn't really concerned about the cost over-runs. He's making additional margin on every change order. He knew this going into the project.... But you thought that a pools a pool. Right??
So, now you're stuck with an under-qualified pool contractor, because you've already signed their contract - back when the pool was under specified.
Now that the specifications are becoming more clearly defined, they are entitled by law to be paid for these changes. You are stuck with the responsibility of these additional costs. "Cha-ching."
Gee... the lowest bidder wasn't so cheap after all.
Having a well defined and specified set of plans, prior to bidding will save you thousands of dollars in the long run. And suddenly, all of the bids become almost equal.
You should stop and think.... does your "design - build process," really force bidders to bid low, keep their observations of deficiency issues with your plans to themselves, until they have you signed on the dotted line???
Maybe you should ask yourself some difficult questions:
Why are some bids so much higher than the rest?
What do they see that the others do not?
What are they going to do that the others won't?
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa©
www.aquatictechnology.com
Wednesday, June 1, 2011
Famous Swimming Pool Designer Paolo Benedetti to speak at 2011 Asia Pool & Spa Exhibition - Design Details and Glass Tile Mosiac Installations
FOR IMMEDIATE RELEASE:
June 1, 2011
Morgan Hill, CA
Internationally renown aquatic designer and builder Paolo Benedetti of Aquatic Technology Pool and Spa, Morgan Hill, CA, has been selected as a guest speaker by the Pool & Spa Exhibition Asia, Bangkok, Thailand, September 20-23, 2011.
This is the largest show in Asia dedicated to the Pool & Spa Industry. His presence at the show will be crucial in presenting the ability of American aquatic designers to this important emerging market.
As the founder of Aquatic Technology, and a Platinum Member of the Genesis 3 Design Group (Murfreesboro, TN), Paolo Benedetti has been instrumental in elevating swimming pools and watershapes as an art form. An accomplished author, he has written countless articles on aquatic design and quality construction. As an educator, he has taught international audiences the finer points of swimming pool and watershape construction.
Paolo Benedetti or his projects have appeared in the Wall Street Journal, CNN, New York Times, USA Today, HGTV, and the following magazines: Robb Report, Lux (Spain), the Affluent Pages, Millionaire, Luxury Pools, Water Shapes, Gentry, Pool & Spa Age, Luxury Homes, Options, Lexus (Lexus automobile owners magazine), Seasons (the Four Seasons Hotels Magazine), Luxury Real Estate, Aqua, and the Franklin Report.
He will presenting 2 seminars during the show:
1. Construction Details - Concealing the "Uglies", Ways to hide things you
need, but don't want to see.
2. Selecting & Installing Glass Tile - What you need to know before & during
the installation.
Paolo Benedetti - Aquatic Artist"Creating water as art."™Aquatic Technology Pool & Spa©www.aquatictechnology.com
Wednesday, May 11, 2011
INTERNATIONAL SWIMMING POOL SPA FOUNTAIN WATER FEATURE DESIGN PLANNING ENGINEERING FIRM FOR ARCHITECTS DEVELOPERS RESORTS HOTELS CONTRACTORS OWNERS
What we do
Paolo Benedetti is the lead designer of the firm. He consults with prospective clients wherein he performs an extensive interview to ascertain their goals, changing lifestyle, how they entertain, how the facility will be utilized, and the construction budgets.
As part of a larger project design team, Paolo functions as a sounding board for other design professionals. He can advise and recommend efficient methods of overcoming problematic operational or design issues, while maintaining the intent and character of the design. Rough ideas and sketches can be transformed into complete construction drawings and construction budgets.
After defining the projects parameters, he creates sketches of proposed elements of the project and of potential configurations of their arrangement. A follow-up meeting with the client allows him to explain how all of these elements function together in the various layouts.
The client is again consulted with and agrees to the various elements to be incorporated into the project and their spatial relationship to each other. Paolo will then create the project plan view and begin to develop individual details of the key elements.
Parallel to the development of the primary elements, the designs of the support systems are developed, engineered and the line schematics created.
Support Systems
The support system designs include many crucial mechanical & electrical systems. Critical systems are designed and calculated to perform at optimum levels of efficiency, minimize installation costs, maximize ROI, reduce operating costs and lower reoccurring maintenance expenses. Their proper design will also ensure that future site needs can be met without extensive demolition or expense.
Electrical
Both low and high voltage distribution circuits are configured and designed to minimize trenching and to provide maximum system flexibility. Complete electrical schematics detail where each conduit and circuit initiates and terminates, and it's purpose.
Low voltage systems are laid out to provide for the integration and control of all of the low voltage needs of the entire outdoor environment: irrigation, lighting, data systems, automation and control systems, outdoor sound, remote controls, security and access controls.
High voltage schematics detail the various circuits required, their purpose and wiring requirements. These circuits control the water feature circulation, heating, lighting, spa jets, filtration, outdoor kitchens, yard circuits, automatic pool covers, high voltage lighting, gate openers, and other apparatus as required by the project.
Hydraulics & Plumbing
The proper design & specification of the plumbing systems is critical to the proper operation of any vessel that moves water. The dynamics of fluid mechanics (hydraulics) can create havoc on an improperly designed system. The flow rates (measured in gallons per minute) and the line velocities (measured in feet per second) are critical in ensuring that the system is energy efficient and safe for bathers. Complete engineering of the system hydraulics also ensures that the system flow rates and velocities are below the maximums allowed by the codes and standards.
Therefore, the entire hydraulic system is laid out and the hydraulics of the system are engineered to determine the total dynamic head (restriction of the entire system to the movement of the water) based upon the required flow and turnover rates. Only after determining the specifications of the hydraulic system are the pumps selected.
Support Equipment
After determining the plumbing requirements of the facility, the support equipment is carefully chosen. The client's goals (as determined at the initial interview meeting) are the determining factors in selecting the equipment. If the client has expressed that need to maximize the ROI and reduce reoccurring maintenance expenses, then higher quality commercial grade equipment will be recommended. If the client was looking to minimize their initial capital outlay (e.g. they planned on immediately selling the property upon completion), then residential (but completely adequate & functional) grade equipment may be recommended. In either case, the client will be given their options, and the trade-offs discussed.
Oftentimes, the area available for the support equipment had been grossly underestimated. Equipment selection and configuration can partially address this situation. However, inventive solutions are often the only means to fit the required equipment into the allotted space. Underground vaults, stacked equipment or elevated filters & heaters allow for the optimum utilization of space.
All of the support equipment is laid out in scale drawings. If stacking or racking is required, then sectional views are also created to illustrate the layout. This assists the installer in visualizing the configuration in it's final form.
Finish Materials
Oftentimes clients have chosen finish materials well in advance of the completion of the design. Sometimes these materials have been chosen by other design professionals, as part of an overall project synergy. Our purpose in this situation is to merely ensure that the materials are suitable for the desired purpose and lifespan. This is only because we will be held liable if we do not advise the client that a material is not suitable for their project (e.g. not frost proof, will dissolve when exposed to pool water, not stain resistant, slippery, prone to decay, etc.). Once the client has been advised of the risks, then they can "move forward" and assume the related liability.
Conversely, some clients rely on Paolo's vast knowledge of materials and installation practices. Paolo sources unique materials from around the globe, one's he's seen in his international travels, site visits to quarries, attendance at materials trade shows, or past experiences.
Complete installation methodologies and practices can be specified for a project if the client so desires. Tile, stone, masonry and concrete installation specifications can all be defined. Paolo's constant and continuing pursuit of construction related education, will ensure the client that their project will be designed in compliance with the latest industry trade practices, published standards, and building codes. The client will not have to worry of their subcontractors are in compliance with the latest methodologies, technology, standards or code.
Structural Engineering
Complete structural engineering is then completed for the project. The engineer will review the various details of the project and will define the support structures to allow construction.
The structural engineer will require a complete geological report (soils report) in order to define the strength of the structures and elements. The soils report also advises the structural engineer of any unusual site conditions that may affect the long-term performance of the structure. Issues such as ground movement, ascending or descending slopes, unstable, expansive or rocky soils, ground water, or unusual surcharges will be outlined in the geological survey.
From concept to completion, or anywhere in between, Paolo Benedetti can assist you in turning your dreams into reality.
Paolo Benedetti - Aquatic Artist"Creating water as art."™Aquatic Technology Pool & Spa©www.aquatictechnology.com
Monday, May 2, 2011
Hollywood Hills Hillside Vanishing Edge Swimming Pool Designer & Builder Paolo Benedetti weighs in on why you need to get a swimming pool designer
Design...
People who create designs for a living understand the importance of a well thought out plan. But many lay people simply cannot grasp the value in spending money for someone to consult on a swimming pool, spa, or water feature.
Value...
The real value is in the savings... Savings, you ask? How can spending thousands of dollars on a swimming pool designer possibly save me money?
Someone with experience can suggest innovative means to overcome obstacles or issues during the conceptual phase - long before they become on-site issues and delay the construction project. They can identify potential problems before they become one. They can offer creative solutions to conceal visual clutter. Their intimate knowledge of water and the way it acts on various surfaces, how it flow, how it breaks, scatters or casts can save the client from living with a constant mess.
Time...
Getting a consultant involved in your project as early as possible, will allow them to weigh in on important issues long before things are "set in stone." Lines of sight, vantage points, colors and reflections, materials and their suitability, and the "all important budgets," can be discussed early on in the project.
A designer can assist in visually integrating the water vessels into the project, landscaping, and help ensure that project timelines will be preserved. This will save the client money, by preventing from having to go back and rework portions of the project that had already been decided.
Architect or Landscape Architect??
Why can't my Architect or Landscape Architect perform this service? A few reasons, actually... education and experience.
While most Architects possess the college education, few if any possess the the combined specialized education about water through history, the physics of water and color, the importance of system hydraulics, the characteristics of water in motion, the construction of vessels, waterproofing, and modern construction technology, and the basics of designing complex water effects.
Decades of experience in analyzing the failed projects of others and actually designing and building complex hillside swimming pools, water effects, vanishing edge, knife edge, and zero edge pools can save the client money. The experienced designer can share the experience of the R&D from past projects that pushed the envelope of watershape design. R&D you ask? Yes - R&D! ("Rework and Demolition!").
Tricks that worked on past projects, solutions to prior issues, or proven techniques used to create an effect can save the client money, by not having to reinvent the wheel. There are people out there who already know that wheels are round, and can get your wheels rolling faster!
Knowledge & Experience
There are a lot of firms touting themselves as pool designers. Some are technicians. Some are artists. Some are engineers. Some are problem solvers. Some rely on computer programs. Some are merely builders. Some are copycats. Very few can do all of the above.
Knowledge and experience do come together... There are only few highly qualified aquatic designers in the world...
Individuals who can do it all (I won't say "know it all" because I am not arrogant enough to say that any of us know it all. After all, I learn something new every day. Sometimes, I even learn a lot of things in one day!).
But of those that possess the skills to perform at an exemplary level in all aspects of aquatic design - I can count them on one hand. And, yes, I consider each and every one of them a friend.
A well thought out plan can only be created, if the people doing the thinking actually possess the knowledge to think the relevant thoughts...
Now is the time to hire an aquatic consultant, before you start the plans for your dream project!
Paolo Benedetti - Aquatic Artist "Creating water as art."™ Aquatic Technology Pool & Spa© www.aquatictechnology.com
Monday, February 28, 2011
How I got started in the swimming pool industry...
A few years ago Paolo was asked to comment as to how he got started in the swimming pool industry.
So, How did you get started in the swimming pool industry?
I made a career move almost 20 years ago. Having had a contractor's license in another trade, possessing the desire to manage my own business, and wanting to utilize my business degree, I purchased an existing pool service company that catered to the affluent estates in the Silicon Valley and on the San Francisco Peninsula.
I quickly realized that managing a "pool janitorial" firm was not my cup of tea. Though I ran a very professional company, the clients did not hold the employees in great regards ("the pool guy" they'd all hear). I also realized that most of the pools that we serviced, were improperly plumbed and constructed using "marginally acceptable" practices. This was primarily because most consumers had been taught to "get 3 bids & to shop price." But consumers don't realize that construction, is not a consumer commodity like a TV or washer/dryer.
Those of us in construction know that there are different levels of workmanship... I realized that there was no one who was actually designing or building top tier vessels. So, I quickly evolved the firm into a remodeling & construction firm, selling off the service division. After realizing that remodeling meant that I had to inherit other builders' inferior structures, I began to focus exclusively on new construction. We still perform remodeling projects, but they must be extensive in nature.
I was confounded as to how a property owner of financial means ended up with such a lousy pool. I came to realized that most developers, general contractors, architects & landscape architects were in the "3 bids" mode... and that breaking that "compete on price" mindset was going to be impossible. I kept hearing "all pools are the same." This only reinforced my theory that they did not possess the knowledge to make a truly informed decision. Someone needed to provide them with the skills to correctly specify the design & construction details of an exotic swimming pool, so that they would not continue to rely upon the "low bidder" to "design-build" from a conceptual sketch (the proverbial "blind leading the blind").
So, I began designing and specifying my own projects. I began consulting with a select group of architects, landscape architects, and designers who relished someone with an education, who was articulate and possessed a knowledge of hydraulics, proper construction practices, architecture, art and world history. Most of those that I routinely work with now, will just set aside an area for the pool or water features. I am then just turned loose with the client. They know full well that what I propose will work with the site, the architecture, and the client's position in life.
I now focus primarily on design & consulting. I build out and manage a select few projects, wherein the clients appreciate a "no holds barred" approach to construction... a "we're doing it right, or we're not doing it" attitude.
Who are the primary influences upon your design style?
The primary influences of my design style have been a direct result of my personal fondness of contemporary architecture. While I can deliver older traditional styles, I usually infuse them with "clean details" (by removing the visual clutter and support apparatus routinely visible in so many projects). I frequently draw on my international travels and studies of art and architecture, to innovate ideas or features that I have seen. I now make it a point of venturing afield while on business trips to Europe, the Middle East, or Asia. I always add on a few days to explore the various museums, ancient sites, history & architecture, at least twice a year. I have also been influenced by the architecture of Legorreta, Barragan, Lautner, and Botta.
What does your pool look like and can you show us a picture?
My personal pool was heavily influenced by the works of Legorreta. It is rectilinear, has massive intersecting planes (walls) with water falling from them. The materials & colors are surprising, yet work wonderfully with the various structures on the site. I'm sorry, though it has been completed for years, I have chosen to keep it as an "unpublished work."
How did you become involved with the Genesis 3 Design Group?
I was "doing my own thing" in Northern California, as one of my friends said so eloquently, "a Don Quixote jousting at windmills." He had attended the very first Genesis 3 Design School. After that school, he said, "my company cannot build to those standards, but they are right up your alley!" I was glad to hear that there were some other like minded individuals, who enjoyed pushing the envelope of their creativity. Folks who relished being the "first" at developing some aspect of a project. I took one of the following Genesis 3 Level I Design Schools & it's all been down hill from there!
All kidding aside, I was relieving to find a group that promoted quality before price, design above computer programs & templates, and uniqueness above volume.
From those humble beginnings as a service company owner, I now perform international design & builds, perform consulting services and forensic case studies, and provide expert witness assistance to property owners. And, now I get to select the clients that I work for.... Over the years, I have actually told some "heavy hitters" that I wasn't interested in working for them. Primarily because they wanted to play me like a "yellow page cookie cutter pool builder" and not the passionate design professional that I am.
They didn't possess the passion to "create water as art" and therefore were not worthy of my efforts... or possessing that "part of me" that I leave behind on their property.
Today, I also consult for other swimming pool contractors who possess the salesmanship skills, but who lack the education, experience, knowledge or creativity to execute these complex projects and effectively resolve design issues.
Paolo Benedetti - Aquatic Artist
"Creating water as art."™
Aquatic Technology Pool & Spa ©
www.aquatictechnology.com
Friday, January 14, 2011
Why most FAUX rockwork look like FAKE ROCKS!
SETTING
Personally, I do not do a lot of rock work, either natural or faux. WHY? Because most clients who want a grotto, volcano, rock formation or waterfall on their property do not have the correct setting. "Setting" you ask? Yes, most pools and homes are built on flat lots.
To make a rock formation appear natural, it must look like it belongs. Have you ever seen a 20 foot high pile of boulders in the middle of a meadow with water bubbling out of the top of it? RARE!! And if there is water bubbling out of some rocks, more than likely the rocks will be small and almost unnoticeable.
It all comes down to the SETTING! Call me a purist, a perfectionist, or an arrogant bastard.... I refuse to put my name or efforts onto something that looks so contrived.
To make matters worse, most poolside waterfalls are so out of scale with the yard that they either look like a wheelbarrow load of rocks left on the edge of the pool by the landscape firm, or an enormous dump truck load of boulders piled to the sky without any rhyme or reason.
The few rock feature pools that I have designed or built, were on lots that sloped up and away from the house. This allowed me to incorporate the rock work into the hillside. It also allows me to create what appears to be the natural source for any waterfalls or flowing water. By creating a stream that begins above the pool's rock formation, the waterfall at the pool appears to be a natural rock out cropping.
QUALITY MATERIALS
Quality work starts with quality materials. To achieve the most realistic looking rock waterfalls, one must work with realistic materials. The MOST realistic that you will ever find are REAL rocks & boulders... PERIOD! If a client's budget allows, I always will specify real rocks and boulders.
Quality faux rocks are cast from real rocks. Rocks that are "carved on site" look like just that - carved concrete. It is impossible to create the natural cleft, cleavage, and striations that occur in nature in the short time the artisan has before the material begins to harden.
Prepackaged "kit" waterfalls, will end up looking like just that... a KIT! In order to make one of these believable, you will need to do a lot of work around the outside of it. And do not think that your minimally build pool can support the additional tens or hundreds of tons weight on the edge without cracking. These ARE NOT something that you can just "add to your pool" (REGARDLESS OF WHAT THE ADS OR SALESMEN SAY - don't do it!). Talk to a structural engineer.... the pool needs to be designed for it. Most backyard pools are not of sufficient structural strength to support any additional surcharges (this is why they apparently crack for no reason - they are as thin as the pool builder could get away with).
A combination of real and faux rocks can help most mid-level projects meet their budgetary constraints. Natural boulders are placed up close to the entertainment areas and where people are the most likely to climb on them. Faux boulders and rock formations can be placed in the background, up high, and in inaccessible areas.
PLACEMENT
Just because quality materials are being used, does not guarantee that the project will achieve stardom. Most projects look contrived because the person in charge of placing the boulders and faux rock panels does not have an understanding of geology and rock formations.
This is not rock-et science. In fact a Jr. High school aged kid could do it. What it takes is the time to stop and observe rock formations in nature. We are trying to mimic mother nature.... so follow her lead.
Most of the boulders that you see in nature (other than those that have rolled down onto the edge of the highway) are buried! What you usually observe is the top 1/4-1/3 of the boulder. But because people are paying by the ton for these HUGE boulders for their yard, no one ever wants to bury most of them.
The simple solution... SPLIT THEM! Duh. Then you actually have doubled the quantity of boulders you have to work with, and saved yourself a lot of labor digging a hole to place it in. It doesn't matter what the split side ends up looking like, does it?? After all this is the side that you're going to put down onto the ground (or maybe buried shallowly).
Piles of rocks in nature usually only occur beneath a larger rock formation... after all, they had to fall from somewhere! So placing a pile of boulders in a yard will almost always appear fake and unnatural. To achieve a natural appearance, requires that either a larger formation is placed uphill from the "rock pile," or a cliff face is created. Either of these techniques can work. The cliff face technique appears more natural when retaining walls are required to shore up steep inclines.
FOOLING THE MIND'S EYE
A true rock artist will be in tune with the natural formation, the angles of the fissures, and the natural "breaks" of the stone. They will incorporate small details that will draw the viewers brain into believing that everything that they see is real.
These details include small pebbles, gravel, and sand set into crevices fissures. Tree roots growing out through the face of cliffs. Plants growing on ledges and plateaus. These elements add to the believability of the rock formation. Even water weeping out of the cliff face, adds an "element of truth."
I'm not going to address the need for structural engineering, supervision of the rock structure construction by the structural engineer, water proofing (which is an ongoing process from the foundation, back fill, curing, sealing, and in the manufacturing of the actual faux rock panels). If your "rock guy" doesn't understand the need for these (or rationalizes them away), then he's a schlock & a charlatan!
When completed, the faux rock work will be very close in appearance to the real boulders that are incorporated into the project. They should last a lifetime without cracking or crumbling.
Be prepared to re-color or re-texture the faux boulders, as over time the finishes will fade due to the exposure to the UV, pool chemicals, and water.
As my rock artists loves to say...
ROCK ON!
Paolo Benedetti - Aquatic Artist"Creating water as art."™Aquatic Technology Pool & Spa©www.aquatictechnology.com