Tech Tips: Re-Roofing Your RV (Part I)

Some years back, the RV industry touted a whole new roofing material called  EPDM (for ethylene propylene diene monomer (M-class) rubber). Said to last the “life of your RV,” it would be a virtually maintenance free roof that should make RVers dance with joy. For a while, it was like that. But with time, RVers began to notice a few problems. For us old “metal roof” RVers, a switch to EPDM roofs brought on a new wrinkle in our maintenance routine: getting rid of the cursed  “black streaks.” Do EPDM rubber roofs cause black streaks? You can argue the point all day, but something about RVs with EPDM roofs seems to attract black streaks.

If black streaks were the only problem, EPDM might be the song and a dance the industry promised. But maybe we need to define what the “lifetime” of an RV is. Three years ago we picked up a 1995 truck camper—our first RV with an EPDM roof. The first hard rain revealed the roof needed help, and we set about making repairs. We noticed the rubber membrane was turning black in places, seemed pretty thin, and no matter how hard we worked at making repairs, there would soon be a new tear in the roof membrane that let the rain come in.
We looked into new “roof coatings” that claimed they’d rebuild the roof with a simple act of “painting” the stuff on. But when push-came-to-shove, after hearing about the state of the roof, the roof coating company representatives suddenly got cold feet. We kept putting on patch after patch of EternaBond, which works great—except we’d simply develop a new hole right next to the repaired one.

As the months—and repairs—rolled on, we noticed that the area of “white” roof quickly shrank, kind of a global warming effect on a small scale. If polar bears were supposed to live up on our roof, they’d be extinct real soon. That old rubber roof was going to have to go—but what to replace it with? Yes, it’s possible to buy and install a new EPDM rubber roof membrane, but did we really want to? We consulted an experienced roofer who’d dealt with EPDM on “sticks and bricks” installations. Roofers got the same song and dance the RV industry got when EPDM was introduced, but the years have shown that while EPDM has its pluses, in his mind, the minuses outscored. Not only does the stuff get thin and become easily damaged over time, it also shrinks and pulls back, leaving the decking underneath wide open to the weather—something we also found happening with our RV roof. His view? Install a new EPDM rubber roof, and sooner or later we’d be looking at the same sad problems we’d already experienced.

An Alternative to EPDM
Not willing to go with the expense and potential repeat issues of an EPDM roof, we looked for an alternative solution. We soon ran into a “new to us” roofing product called Peel and Seal. Manufactured by MFM Building Products Corporation, Peel and Seal is a multi-layered roofing membrane that starts with aluminum on the “weather” side, and ends with a very sticky thick layer of rubberized asphalt. A backing paper keeps the sticky stuff where it belongs until it’s time for installation—peel off the backing paper, roll out the membrane, apply pressure to it, and the new roof is in place.

Other specifications of Peel and Seal made it sound like just the thing for our project. It was lightweight—scaling in at about 30 pounds per 100 square feet. That’s a bit more than EPDM, but certainly not outrageous. Its self-sticking attitude eliminates the need for glues and weird fasteners. It is said to be puncture resistant—great for those jaunts out in the back woods—and if damaged, is easily repaired. And what about cost? With shipping you can figure somewhere around $120 for a 100-square-foot roll.

But would it work in the RV environment? We called the company and had a heart-to-heart with the company’s technical guru. He assured us that if we met the roofing material’s requirements to start with, that Peel and Seal would be an ideal material for an RV roof. He was so convinced he offered to provide enough of the stuff to cover our rig’s roof as a test subject. This story is about how we installed a new Peel and Seal roof, and our observations of how well it’s worked out since our installation last fall.

Preliminaries
Remember, we mentioned that Peel and Seal is an ideal material for an RV roof, provided you meet the requirements of the material to begin with. What are those requirements? First, a completely flat roof is a no-no. Peel and Seal needs a minimum pitch of a half-inch of slope for every foot. Ponding water can cause problems—even resulting in leaks. Our camper roof had plenty of pitch in places, but a large area of the roof was dead flat. What could we do to meet the needed slope?  It took a lot of doing—and digging—to figure out the answer to that question.

After pulling back some of the old EPDM rubber, we found the previous camper owner had really let things slide. It looked like low-hanging branches had done some damage to the roofing, and the owner had simply parked the camper and let it sit through an Oregon winter. The original 1/8-inch-thick “plywood” was completely shot over a large area. We needed to learn what was under all that mess. The tear-off was to begin.

Should you decide to remove an old EPDM roof, be sure you wear work clothes you don’t mind tossing out when you’re done. Under that nice white layer hides the “dark side.” Some RVers have described this stuff as “lamp black” and if you’ve ever cleaned a kerosene lamp chimney, the description is perfect. Equip yourself with work gloves, as the black junk is powdery and it quickly works itself into your skin, under your fingernails, and of course, when you scratch your nose, your beak will look like Old Nick himself hit you in the snoot. Work jeans and work shirts, shoes and socks, all of these were tossed at the end of the process, and any time before these had to be washed, they had to be washed separately from all other clothes, and the washing machine itself scrubbed down—it’s awful!

Prior to a tear-off, there’s plenty of work to be done. All accessories and trim must be removed from the roof. In our case, that meant solar panels, roof vents, a luggage rack, roof ladder, plumbing and refrigerator vents, and metal edge trim. And don’t forget the a/c unit, either. RV manufacturers seem enamored with the idea of using plastic up on the roof wherever possible, and we found that UV eats the stuff up. Be prepared to replace plumbing vent caps, and don’t be surprised if the refrigerator vent cap—if plastic—will disintegrate on removal. Ours did.

With all the trim and accessories removed, it’s easy to see where there are cutouts in the roof for pipes, vents, etc. If you’ll be replacing the deck material itself, now is the time to carefully chart the locations and sizes of all cutouts so you’ll be able to make cutouts in the new decking.

Before we set about pulling all those accessories from the roof, there was one more safety issue at hand. What with the dangerously rotten spots in the roof, we were concerned we might actually come down through the ceiling. In fact, inside the rig an obvious sag in the ceiling around the area of the air conditioning unit gave us plenty of concern. To shore up this area during the repair process, we laid 2 x 4 lumber up against the inside of the ceiling in that sagging area. To support them, we ran more 2 x 4s vertically and attached them to those at ceiling level.

We didn’t cut those verticals to run from floor to ceiling, but rather, set trailer-stabilizing jacks on the floor under the upright 2 x 4s. The “two-bys” were cut to a length that allowed us to adjust the stabilizer jacks to gently push up on the bottom of the two-by. We then had an infinitely adjustable system that allowed us to push the ceiling back in place, and hold it there until we could fix the problem that allowed the sag in the first place. To properly “mate” the top of the leveling jack to the bottom of the 2 x 4 upright, we placed a 2-inch PVC pipe cap on the end of the upright, holding it in place with a wood screw.

Getting the solar panels, and vents off wasn’t a problem. A cordless drill with an extra battery or two and the appropriate bits make the job a breeze.

Perhaps the best way to deal with the old rubber roof is to whack a line across it with a sharp utility knife, grab hold of the old rubber and just peel it back off the decking. We took garbage bags up on the roof to stuff the old junk in, lest the wind grab the stuff and really mess up the neighborhood. With the old rubber roof out of the way, a crowbar and hammer quickly pulled what sound “plywood” was left from the roof framing. It got tougher where the luan plywood was rotted, but perseverance and sweat soon left us with the roof framing exposed and ready for evaluation.

Next month, we’ll address fixing framing, building in slope, and installing Peel and Seal.

Russ and Tiña De Maris are authors of RV Boondocking Basics—A Guide to Living Without Hookups, which covers a full range of dry camping topics.  They also provide great resources in their book, Camp Hosting USA—Your Guide to State Park Volunteering.  Visit www.icanrv.com for more information.

Russ and Tiña De Maris