Q)  What precautions do Heating and Cooling technicians need to take when working on a roof?

A)  When we have completed a TPO membrane roof, we inspect it for voids in the seams and for punctures.  We usually don’t find anything during these inspections (called probing) but it is a helpful assurance against a leak.

Often we get a call from a building owner four months to several years after the roof has been completed and they report a sudden leak in the roof.  This is usually due to a puncture from someone on the roof.  It does take a lot of pressure to make a hole in a roof, unless one is dealing with sharp tools or edges of panels from an HVAC unit or swamp cooler.  Technician awareness when working on roof top units is simple and helps prevent leaks.

One example of a leak in a TPO membrane roof caused from a rooftop A/C unit installation occurred about two years ago.  We installed a nice white, energy efficient TPO membrane roof on a condominium complex in Saint George in 2004.  In 2008 I got a call from the management company reporting a leak in one of the units.  Amid my suspicion, I took a trip down to investigate the problem.  When I got there, I saw that a new A/C unit had been installed over this condo unit.  I took some membrane cleaner and started wiping the membrane clean.  It didn’t take long to find several holes in the membrane caused by fragments of hot solder from the installation process. 
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The best precaution against this is for the HVAC technician to place a 3’ x 3’ piece of OSB or plywood down under the welding area.  This will prevent any extremely hot fragments of solder from coming in contact with the membrane.
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Fortunately, the repair was simple.  I just heat welded a new peice of TPO over the area and their problems were solved. 
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That is one beautiful characteristic about this product.  It does not lose it's weld ability like PVC and EP Sheets do.  I was just on an extremely large food processing plant roof yesterday that was done about 15 years ago in an EP Sheet.  A general contractor just put two new exhaust units on the roof.  As we tried to weld new membrane flashing around these units, we found it had lost its weld ability.  We have found a solution that I won't go into now, but the fact is it couldn't be welded after this time frame like a TPO membrane could.

It made me all the more comfortable installing roofs for our customers!
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What Is TPO? 03/09/2010
 
Q)  What is TPO?  

A)  TPO (Thermoplastic Olefin) is a single ply membrane which is used on Commercial and Residential buildings.   Because the membrane is thin, ranging from 45 to 80 Mil’s thick, it is light in weight yet durable and remains flexible to accommodate the expansion and contraction typically endured in Utah’s climates.   More technically speaking, TPO is a trade name that refers to polymer, polyethylene, polypropylene, BCPP, rubber, and a reinforcement filler.  This roof system is taking over the construction industry because it remains flexible (like EPDM) yet has heat weldable seams (like PVC) and is usually white, which saves significantly on energy costs.  

When TPO was new to the roofing industry, it underwent the typical developmental challenges (quite similar to PVC membrane’s issues).  But the reputation of Versico is head and shoulders above the rest as it has consistently provided a high quality roofing solution.  Most TPO manufacturers have figured out a long lasting formula for their TPO’s, but Versico continues to lead the way.

In February of 2010, an article was published by the National Roofing Contractors Association (NRCA) informing consumers of the likelihood of accelerated aging in certain conditions where the UV rays concentrate on the membrane due to reflective surfaces that are adjacent to the roof surface.  Examples of these surfaces would be large mirror windows next to a roof surface, or reflective flashing on a wall above the roof. Accelerated deterioration from focused UV Rays is not necessarily unique to TPO, but because TPO is becoming so widely used today, the article focused on the TPO roofing membrane needing to be upgraded in situations such as these.  Once again Versico has led the way in this solution.

Every Versico Membrane is enhanced with Octaguard XT Weathering Package in its sheet.  This enhances the product to give more life to the sheet.  In fact the Versico TPO membrane can withstand over 60 days at a constant 275 deg F without showing signs of material failure.  Most others don’t withstand this lab test without showing deterioration.

Aside from the material quality, there is still one major consideration:  Any roofing system is only as good as the roofing technicians who install it!   It doesn’t matter how good the material is, if the installers aren’t experienced, the quality level of the entire roof system will suffer.  Seek out a company who has been installing TPO membrane for at least 5 years.  Brady Roofing has been installing TPO full time for 12 years on Commercial buildings as well as Residential homes.  We are factory trained and certified.  Please check us out with the BBB of Utah and learn more about us on our Website at www.bradyroofing.net.

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