Saturday, January 26, 2013

Expert Swimming Pool and Spa Advice from International Designer

The causes of most construction defects are directly attributed to one of 2 causes - failure to follow instructions, plans or project specifications and/or the lack of qualified supervision.
 
Failure to Follow Instructions

Most defects in construction projects are directly attributed to someone not taking the time to READ instructions.  Whether they be the product usage insert, manufacturer's installation manual or the engineer's plans and notes... failing to take the time to read AND understand the instructions results in errors.

Sometimes these errors can be huge - incorrect strength or diameter of steel, walls that are too thin, pipe diameters that are too small or electrical systems that are incorrect.  These types of errors can result in a project that may be structurally unstable or dangerous to swimmers.

When these instructions refer to another code or standard, it is the installers responsibility to seek out and understand those codes as well.   

In the plans if the structural engineer states, "Shotcrete must be installed in compliance with ACI 506R-05," then the installer must understand what those standards require 

The structural engineer does not need to reprint the entire referenced standard in the plans.  Why?  Because anyone who installs shotcrete as a part of their business should already be aware of, possess a copy of, and be following the requirements of ACI 506.

If the instructions that are enclosed with electrical components are not read and adhered to, a potentially life threatening situation can be created.  The failure to properly bond metallic components can result in a fatal electrical shock.  Though most electrical components clearly state how they are to be installed, many will also refer to NEC 680 & 682.  Again, anyone who builds swimming pools or fountains should have a copy of these codes and be intimately familiar with them.

The Lack of Qualified Supervision

Note the word "qualified?"  Just because a project has on-site supervision does not mean that the supervision is worth anything.  The supervisor may just be directing the progress and may "no nuthin' 'bout da details uf da wurk."  Therein lies the problem... the blind leading the blind.

The person who supervises the work of others, needs to know how that work is to be performed.  The person supervising the design, planning and construction needs to be familiar with:
structural engineering
soils
excavation 
building forms
hydraulics
plumbing 
electrical
reinforcing steel
shotcrete (wet or dry mix methods)  
tile
masonry
plaster
concrete
mechanical (venting)
fuels (approved piping, venting, shut-offs)
automation and controls 

This is not to say that they need to be a licensed expert in each of these fields.  But, it is saying that they need to know enough about each topic to question what others are telling them is right.  Anyone can make a mistake, even experts that the contractor may hire.  

The contractor needs to understand that pools with diving boards must comply with various floor contour and shape requirements, and which diving boards can be safely used in each.  They must ensure that the project design and engineering complies with these codes and minimum dimensional shapes.

The swimming pool contractor needs to be able to recognize differential soils or buried trash during an excavation.  They need to be smart enough to have the structural and soils engineers weigh in on the discovery.  It may mean nothing or it may be a big deal - but they need to let the experts decide which!

The contractor needs to understand the basics of hydraulics and the Virginia Braeme-Baker Safety Act, in order to deliver a swimming pool that is safe from entrapment hazards, unwarranted restrictions, high energy consumption and cavitation.  The need to ensure that the suction point sumps are the correct size, are compatible with the flow rate ratings of the drain covers and if sumps are field fabricated, that they meet the requirements of the VGBSA.

The supervisor on the project needs to know what each of the sub-trades are required to do.  Whether it is the electrician, plumber, mechanical, masonry or concrete sub-contractor - they need to know the codes and standards that apply to each.  And they have a duty to ensure that these codes are followed and complied with - even if the local inspectors do not enforce the codes.

Because when the client has any doubts about the project, an expert will come in and dissect the project.  Each component of the pool that is found non-compliant may be required to be corrected.  Tearing out completed work to repair underlying defects can quickly consume any project profits.

And anyone in construction will agree... it is cheaper to do it right the first time!

Take the time to READ and UNDERSTAND the plans and installation instructions.  

Employ QUALIFIED project supervisors or go get educated... there are some excellent programs on swimming pool construction available.  The $3,000 spent on one of these programs, will save you much more than that, if an expert is ever hired to evaluate one of your projects.


Paolo Benedetti 
Aquatic Artist, Consultant & Construction Defect Expert Witness 
"Creating water as art."™ 
Aquatic Technology Pool and Spa 
©www.aquatictechnology.com

Wednesday, January 16, 2013

Swimming Pool Design Deficiencies

Swimming Pool Design and Construction Expert, Paolo Benedetti, discusses common swimming pool design inadequacies.  

Proper Planning

We've all heard the old adage "Proper planning prevents piss-poor performance."

If the person doing the planning has a limited education and knowledge base, then all of the beautiful plans in the world will not keep the "boat from sinking."

Proper planning requires knowledge of hydraulics, cement and masonry, some engineering details, electrical, waterproofing and drainage, sanitization, and equipment selection/technology.

It may look pretty on paper, but it might not work in reality.  An example...

Plan Review

I was recently asked to "bid" a job.  After explaining that I do not "bid jobs," because it implies that the client is only concerned with price and not quality (low price and quality are diametrically opposed).

The potential client sent over some beautifully drawn CAD plans.  The project had everything...  a swim up bar, fire features, a detached elevated perimeter overflow, water features, beach entry bubblers and dramatic lighting effects.

As I reviewed the plans, I discovered a number of flaws.  The equipment room was grossly undersized for the amount of equipment (on the specifications list) that would be needed to make everything operate correctly.  No one bothered to lay out the equipment room to scale, to even determine if it would fit and if there was enough room to ever service or repair it.

All of the water features and bubblers were going to operate off of one variable speed pump.  Automatic valves were going to modulate the the on/off of the various features. Good theory - bad practice.  The specified plumbing was undersized and the plumbing design was "unbalanced."

The lighting that was specified for the beach entry and bubblers could not be install in that shallow of water.  The designer did not know the capabilities of the equipment he was even specifying.

The yard was a flat lot, and there was no place for water in the sunken seating or bar area to discharge to.  No other provisions, such as a sewage ejection sump and pump were provided for.

The spa was detached from the pool.  The water level in the spa was to be 18 inches above the pool.  After the water overflowed the spa walls it was supposed to flow into a gutter/rill.  The rill was then going to drain across the pool deck & into the pool.

Great concept, but the gutter had no change in elevation - nothing (gravity) to force it to drain towards the pool.  In fact the bottom of the gutter was 6" below the deck & the pool water level was 5" below the deck.  Water was going to flow BACKWARDS from the pool into the rill.

Only a small percentage of the population has the ability to visualize single dimensional plans in three dimensions.  This is why many projects are designed with inherent flaws that later reveal themselves during construction.

Only cross sectional details will uncover these errors and omissions.  Something most clients are unwilling to pay for...

By the way.. the client thought that my fee for reviewing the plans and completing the necessary details was "...crazy.  The project is already designed."

Little does he know.... he's going to spend more on change orders to modify the project or to correct these problems later, than if he'd paid me my fee.

It's what you don't know (or worse yet, what your "pool designer" doesn't know) that'll bite you!


Paolo Benedetti 
 Aquatic Artist, Consultant & Construction Defect Expert Witness 
"Creating water as art."™ 
Aquatic Technology Pool and Spa 
©www.aquatictechnology.com