They are basically maintenance free for up to ten years. However, many folks like to was off with soap. A presenter from the roofing material manufacturer once made this comment at an FMCA rally and some one in audience said his RV was next to his house and when he looked out the window he could see the dirty roof. The presenter told him to move the RV. LOL
Here is Dicor statement which does address cleaning
Truth About EPDM Rubber Roofs
bullet EPDM Rubber: What it is and why it lasts so long.
bullet Proper Care: What manufacturers actually recommend
bullet WATCH OUT! For RV products that can damage EPDM rubber & void your warranty!
bullet How to keep your EPDM rubber roof clean & looking like new.
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?
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?
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.
Dicor Corporation · P.O. Box 1806 · Elkhart, Indiana 46515
Tel. (219) 264-2699 · Fax (219) 293-2017 · Toll Free (800) 837-2059