Overview
EPDM is one of the most versatile and long lasting
materials ever manufactured for outdoor exposure. Most RV industry experts
consider EPDM rubber roofing membrane the most dependable, most cost
effective and easiest to maintain roofing material there is. Yet, today's
average RVer is deluged with information, a great deal of it
misinformation. Consequently, RVers are spending millions on unneeded
products, many of which can be harmful to EPDM rubber roofs.
This Public Service Announcement details the truth about
EPDM and reprints manufacturer's guidelines on cleaning and maintaining
the EPDM rubber roofing membrane on your RV. If you have questions after
reviewing the material, please contact Dicor Corporation, the RV
industry's largest supplier of EPDM rubber roofing. Dicor's address and
phone numbers are provided.
Mis-Information, Mistakes & Money
EPDM stands for Ethylene Propylene Diene Monomer.
Engineering specifications describe EPDM as, "Ideal for outdoor
applications because of its excellent resistance to ultra-violet light,
ozone, oxidants and severe weather conditions."
EPDM rubber roofing membrane is made to last 20 years or
longer and has a 10 to 12 year guarantee depending on the brand. The
guarantee does not require the use of any protective 'roof treatment' or
'roof protector' product and recommends only cleaning. Unlike natural
rubber (latex) or blends (tires & wiper blades), EPDM does not require
periodic applications of any product to protect it from ultra-violet light
or ozone.
The statement or implication that you should purchase
and apply a product to "protect" your rubber roof the elements
is misinformation. Buying and using such a product can be a mistake and
may even damage the EPDM membrane.
Petroleum Distillates... Not for EPDM
Petroleum distillates are incompatible with and should
never be used on a number of plastics including vinyl and rubbers,
particularly EPDM. Engineering specifications rate EPDM's solvent and oil
resistance as "POOR". Dicor's Care and Maintenance instructions
warn:
"CAUTION: DO NOT use cleaners or
conditioners containing petroleum solvents, harsh abrasives or citric
based cleaners. You may cause irreparable damage to your roof."
Laboratory tests conducted in July of 1996 evaluated the
effect of a leading RV "roof treatment" product on EPDM roofing
membrane using standard sunlamp and immersion testing procedures. The
"roof treatment", which contained petroleum distillates, caused
a 63% mass change (swelling). In the summary/recommendations portion of
the lab test the scientists stated they would recommend the "roof
treatment" and more tellingly noted, "Per the MSDS, this product
contains petroleum distillates, a substance that is known to be
INCOMPATIBLE with... EPDM sheeting".
For your rubber roof, for the EPDM door and truck seals
around slide-outs/pop-ups, in the baggage compartments or for the EPDM
door and trunk seals in your car, petroleum distillates are a huge
"no no". And don't be fooled by names such as "organic
solvent", "hydrocarbon carrier", etc. Petroleum distillates
by any other name should NEVER be applied to EPDM. If you aren't sure
about a product, contact the manufacturer and have them send you a copy of
the Material Safety Data Sheet (MSDS). Look under the section entitled
"HAZARDOUS INGREDIENTS". If it lists any petroleum distillates,
do not use it on EPDM.
Frequently Asked Questions
Q: Is it necessary to protect my rubber
roof against UV light?
A: No.
Q: What do I need to do to care for my
rubber roof?
A: Periodic cleaning (See Dicor Care & Maintenance
instructions)
Q: One manufacturer told me their roof
treatment product had only a minor percentage of petroleum distillates,
something like 20 or 30%. Does the percentage matter?
A: No. Usually percentages given are based on weight.
Since petroleum distillates are significantly lighter than water, in
reality 30% by weight might be 40% or more by volume. But the percentage
of petroleum distillates doesn't matter. THERE IS NO LEVEL OF PETROLEUM
DISTILLATES THAT IS RECOMMENDED.
Q: If I use a roof treatment product
containing petroleum distillates on my rubber roof, can that void my
warranty?
A: Yes
Q: If I'm going to buy a used RV and it
has a rubber roof, how can I tell if the previous owner used petroleum
distillates and damaged the rubber roof? What would the damage look like?
A: Two things: First, swelling. Uneven thickness of
material. Second, loose areas. Petroleum distillates soak in and cause the
adhesive to loosen and the membrane to balloon. Then, when the ballooning
goes down, it may never again adhere properly or completely.
Q: Is it easy to repair tears in the
roof membrane?
A: Any tear in an EPDM roof membrane can be repaired
using a number of repair methods. Dicor has a prepackaged peel and stick
repair kit that works well on small tears (up to 8"), a larger kit
that should be used on larger damaged areas, and also rolls of peel and
stick material for long, narrow tears.
Q: Oxidation: My roof seems to oxidize
and run down the sides when it rains. What's going on?
A: First, EPDM roofing membrane does oxidize slowly; it's
supposed to. In a dozen years it may oxidize 10% of its thickness. This is
normal. Cleaning at least four times a year will help greatly, more often
if your local conditions and experience warrant.
Q: The rubber roofing wraps over
slightly on both sides of my RV and you can see it from the ground. It
gets dirty and doesn't look good. What can I do about this?
A: Clean the area and treat it with a product that will
repel soiling and is safe for EPDM. One product that performs and lasts
well, is safe for EPDM and is commonly available at RV stores is 303
Protectant.
