Some of the best RV roof coating brands are Dicor and EPDM. RV manufacturers usually use EPDM or TPO rubber roofing material, and it is important to use only products that are made for these types of rubber roofs. If a product works on a normal brick house, do not use it on an RV, as applying the wrong product can cause a dramatic drop of the RV's resale value.
Most EPDM roofs do not require any maintenance for the first 10 years other than washing occasionally with soap and water. However, using harsh chemicals or petroleum-based products on an EPDM roof may cause irreparable damage. When buying an RV with an EPDM rubber roof, check the roof first, and make sure it isn't swollen, uneven or loose, as all are signs that the previous owner used a damaging chemical on the roof surface. Apply two coats of Dicor on an EPDM roof after using the company's cleaner to reseal the roof.
TPO roofs are shinier and more rigid than EPDM roofs. It is uncommon for a TPO roof to need any sort of coat, as a soapy wash and a mop up take care of TPO maintenance. Protect-All Rubber Roof Treatment and Murphy's Oil Soap are reliable products to use when treating the roof or taking preventative measures.