RV Roof Replacement PART 6: Installation of new TPO membrane

RV Roof Replacement Project

PART 6: Installation of New TPO Membrane

For some reason, we thought this step would be easy. I mean, what could go wrong with simply slapping on some adhesive and covering it with your new membrane? Well, we messed up. And it almost cost us the entire project.

For this part, we bought a flat broom and a painters kit which included a pan and a roller. We also bought a Dicor-brand TPO membrane from Amazon along with a Dicor EDPM/TPO membrane installation kit. Our plan was to position the membrane on the roof, roll it out to make sure it was enough, apply adhesive, and then re-roll the membrane on top of it. 

The first part went off without a hitch. We placed the membrane on the roof and carefully unrolled it. We had plenty (our camper is 33' and we bought a 35' membrane) so we carefully rolled it back up and started on the adhesive. 

An important note is that we started rolling the adhesive about a foot from the front cap with the plan to finish this part at the very end. One of us began rolling our adhesive on in generous amounts while the other unrolled the membrane. We quickly learned that you absolutely CANNOT walk on the membrane after applying as the membrane would bunch up and create a horrible patch that was full of bumps. So, after rolling on the membrane, the broom was used to press the membrane onto the adhesive and to smooth out any bubbles.

The BIG mistake that we made was that after initially rolling it out, we neglected to make sure that we rolled it back up perfectly straight. As a result, the membrane started to go on at a slight angle, and we would've been in BIG trouble if we got to the end and there wasn't adequate overhang to reattach the side bars. We couldn't start over because the membrane was already covered in adhesive. So, what should've been a fairly easy job of unrolling the membrane became one of the biggest stresses of the entire project. Thankfully, we ended up having just enough on either side so we escaped a MAJOR bullet. 

Mostly-completed roof

After reaching the end, we slashed an "X" into the rear bedroom window and made our escape out of it and waited a few hours to let the adhesive dry.

"X"'s cut into membrane over openings

We later returned to roll the adhesive onto the front part of the roof. We ran into a problem where we couldn't decide whether to install the roof OVER the front cap, or UNDER it. We watched a few videos that swore by placing it OVER, as in theory any water that gets under the front termination bar will simply slide off the top and not travel under the front cap. The original membrane was installed UNDER the cap so we had to make the decision to try something new or keep it as is. Fortunately, that decision was made for us when we realized we couldn't get the new membrane under the front cap so we ended up placing it over. 

Rolling on the rest of the membrane