TPO Roofing Systems by Best Affordable Roofing in San Antonio.
Business and homeowners who are looking to replace their old flat roofs often choose to install a TPO membrane, without being aware of some very important problems that exist with this roofing material.
Since TPO is very well marketed in both residential and commercial roofing markets, offers a good price point and a number of attractive features, many people don’t think twice before putting a TPO membrane on their roof.
Lets take a closer look with at some concerning problems that TPO roofs have, to help you decide whether this is the right roofing material for you.
What Is The Problem With TPO Roofing? Answer from Best Affordable Roofing in San Antonio.
One of the major issues with TPO roofs has been premature aging and seam failures due to prolonged exposure to intense heat.
TPO membrane failures were particularly frequent in the states that experience the most heat and UV radiation all year round.
NRCA urging roofing contractors to be aware of these issues and take extra precaution when installing TPO roofs.
Moreover, MRCA called a panel of TPO manufacturers to take a closer look and discuss these problems.
Since TPO was documented to be experiencing major problems, it would be expected that both organizations would continue to periodically issue updates for roofing contractors.
However, there have been no updates since the dates of the initial advisories and discussions (about 5 years).
Here is a “printout” of MRCA TPO Advisory – we added it since it has magically disappeared off MRCA / NRCA / Roofing Contractor Magazine and other prominent roofing publication websites.
ASTM International was also closely involved, and worked on testing the membrane, as well as revising and improving standards for TPO formulations.
The last revision of ASTM D6878 TPO standard, dates back to 2011, at which point the organization stated that further tests and research will be conducted and more updates will follow. However, it has been over 5 years, and ASTM has not issued any updates.
In a nutshell, the latest revision of ASTM standard (Revision D6878-11a) required the top ply (weathering surface) of a TPO membrane to be increased by 25% from 12 mil to 15 mil (15 mil = 0.015″).
A typical TPO membrane installed today is 60 mil in thickness, thus even by new standards, the weathering surface of the membrane is still only 1/4 of total thickness.
However, in the standard’s review article by RCI, the conclusion is that 15 mill is sufficient, and 25% thickness increase provides exponential (not linear) growth on increased membrane life – source.
Do note however, that this report was written by two Carlisle Syntec employees, which is a major manufacturer of TPO in the US, and therefore is “somewhat subjective”.
Other “post-ASTM-revision” concerns that we have are: when will the new standard be applied in the manufacturing process, and how will it affect the cost of TPO roofing?
1) How do you know if the TPO membrane installed on your roof was manufactured after “D6878-11a” was issued and meets that standard? Many suppliers are sitting on excessive inventory of “old” TPO membranes, and will want to get rid of them as fast as possible.
2) Contractors will want to buy seemingly inexpensive TPO materials, without any concern for which generation it is. Most contractors do not even know anything about these standards.
3) The cost of TPO roofing that meets D6878-11a revision will increase drastically. Manufacturers will have to use significantly more expensive raw materials in the top ply.
The bottom ply has no UV or weathering stabilizers, as it is not exposed, and therefore is much cheaper per 1 mil to produce.
Hence the bottom ply is so much thicker than the top ply (cost cutting and maximizing profits). How will this affect the final cost to consumer?
Best Affordable Roofing in San Antonio, Information On TPO Membrane Performance From Manufactures
TPO roofing manufactures have not posted any new information on their websites about TPO performance, simply ignoring the issue.
The only company that addresses durability and performance of TPO in detail and provides assurance of their product’s quality is Versico ( a private label for Carlisle).
The company provides in depth educational information on TPO for their clients, which is in sharp contrast to the minimal information found on other manufacturer’s sites.
Recently, GAF put out a comparison study of their TPO membrane products vs other manufacturers, which was supposedly conducted by an independent laboratory.
Surprise, surprise GAF’ TPO roofing products significantly outperformed the others. We will review this study in greater detail in a separate post.
Finally, a Google search on “TPO roofing” and related keywords returns no posts in the last 12 months that would address the issue and shed light on whether TPO membranes have been performing well.
You do however get many generic articles extolling the benefits of TPO roofing as a durable, inexpensive and energy efficient material.
Savvy consumers should wonder whether this overall silence means that the problems have been addressed, or that they are being swept under the rug, because TPO roofing is such a lucrative and profitable business.