There are two very simple reasons why people put rubber roofs on their RVs: It’s low weight and it’s very cheap compared to fiberglass and aluminum alternatives. It’s also not that hard to do on your own, if you know the proper steps.
- Measuring tape
- Masking tape
- Metal shears/band saw
Remove metal roof
To remove the metal roof, you can use a band saw. Metal shears will also work but it will take longer.
Clean roof surface
After you’re done removing the roof, you have to clean the roof surface or decking. You need a smooth surface area to install a rubber roof properly and ensure that it’s well sealed.
Use an electric sander to get the job done faster. Maintain the same movement, either left to right or back and forth. This will prevent over-sanding. If you’re using sandpaper, you should start with coarse sandpaper and gradually switch to finer grades as the deck starts looking smoother.
Install leak prevention
All rubber roofs should come with their own deck extension which serves as a waterproofing feature. It will allow water to fall into the gutter instead of staying on top. Install it according to the manual.
Relax rubber membrane
To achieve a perfect molding, you need to let the rubber roof relax. Depending on how thick the roof is you may need to let it sit on your roof for over half an hour.
Adhere the roof
This is where having someone to help you goes a long way. To adhere the roof, you need to apply the glue on all the surface area of the decking, not just on the edges.
You can do this with a roller. Also, to make things easier, fold about half the rubber membrane back so that you can apply glue underneath.
Unfold it into position and repeat the process on the other side.
Clean rubber membrane
By cleaning the top of the rubber membrane, you’re helping to push it down. This will pop any air pockets between the membrane and the decking.
Apply adhesive to the roof perimeter
Add a thin coating of glue (or whatever the recommended adhesive) to the perimeter of the roof. Once it’s dry, put in the roof membrane. You should also cut any excess membrane that’s hanging off the edges.
Add additional waterproofing
External corners may need additional waterproofing. You can use a special material such as Elastoform or anything else that the rubber membrane manufacturer recommends. Cut it to size and then add rubber primer to a surface area that fits your cutout.
When the primer is dry, you can install the waterproofing material. Be sure to push down hard as it will need lots of pressure to stick.
Install the rubber roof
At this point, you can add adhesive to the flanges of your deck and then you can lift up and position the rubber roof into place. Letting it dry overnight should be enough.
Reinstall vents and AC units
If you have to reinstall vents and AC units, now would be the time, after the rubber roof is glued in place. Cut new openings to size using a measuring tape to figure out how long the edges should be. Use sealant to solve any potential leaks from the new cutouts.
Check joint seals and waterproofing
After the sealant has dried, start splashing the roof to check the waterproofing. Focus on the joint seals and on the vents and AC units to make sure everything is sealed.
Tips and Warnings
- Because you’ll be working with a lot of glue, you should use a mask. Adhesive fumes are toxic and installing a rubber roof takes a while
- Don’t try to do this alone even if you know that you can lift the roof on your own. The roof needs to be placed in the proper position and not pushed or dragged into place. That will mess up the adhesive
Although some rubber membrane manufacturers might recommend their own brands of adhesives and glues, it doesn’t hurt to look at the top popular brands of the market. There’s a good reason why some sealants and waterproofing materials are in high demand.