The rain won’t come to let me test to make sure no water’s coming in. Not that I see how it could, as the entire roof surface, including up the base of the skylight, is completely covered in rubber…. It took about a week to remove the old roof and finish applying the new one. This is another picture-heavy post to try and illustrate the steps I took. Here goes!
Day 1: Removed the metal roofing, with an assist from my ever-so-helpful neighbors. The caulking I’d used to try and waterproof it is so sticky, I couldn’t get the front piece out from under the drip edge to the slanted portion. I needed more muscle to tear it away. That damaged the drip edge badly enough so that it needed to be replaced. The new solution works, but it’s not as cute. Oh well.
EPDM caulking is applied and hopefully the roof leak is cured (not true, as it turned out)
Caulked metal roofing
Days 2: Painted underlayment plywood with an oil-based primer (I used Zinnser, which is awesome, and very versatile) to allow the liquid rubber roofing a good adhesion. It took me a while to get used to this stuff, as it doesn’t spread easily, instead needing to be “dragged” by the brush and forced to go where I wanted it. Each piece took almost an hour to paint. It does dry quickly, so if I hadn’t run out of energy I could have dragged the panels up and started installing them the same day.
Thin and smooth, the underlayment I used to cover the original roof sheathing should be easy to handle by myself and also make a good base for the new roofing.
Days 3 and 4: Glued and screwed down the wood, and covered each hole and crack with butyl tape and polyester cloth. Working with the butyl was fun, like being in an art class at camp. It’s like a sticky clay..sort of. It’s often used on boats, as it’s unbeatably weatherproof, and even holds up if underwater. It’s also recommended for use with EPDM. You CANNOT use anything with silicone or that asphalt-impregnated stuff with EPDM. The polyester cloth wasn’t necessary for the flat surfaces of the roof, but does give the liquid rubber something to grab hold of. I bought it primarily for the vertical surfaces of the skylight base, which is where the pesky leak was. I thought it might also be useful for the edges of the new roof, to allow me to cover them and yet keep the stuff from dripping down the new flashing. It mostly worked. I did have to wipe off (with mineral spirits) a very few drips. I also think I’m going to reinforce the edges with uncured EPDM tape, as I want as much protection from low-hanging branches as possible. This is seriously sticky stuff. You’ll want to keep it in the fridge before using it on a hot day, trust me. It cures in the sun over time, just like the liquid EPDM does.
Primered underlayment is secured to the original roof sheathing, and now I’m using the butyl tape and polyester cloth to cover any and all holes, cracks, gaps, and around the edges and up the base of the skylight. The roller is necessary to smooth down the butyl.
Filling in the cracks between sheets of underlayment
I took a piece of butyl and rolled it in my hands to make a “snake”, then used the polyester over the top and rolled it smooth
Day 5: This is really where I needed to take deep breaths, as it was time to open the cans of liquid rubber, and start applying it. No turning back once the catalyst is added! I need to warn you, this is potentially very messy. Especially if you tend towards clumsiness as I do. I ended up tossing out all the clothing I was wearing that day, including my shoes! See, you have to use a special mixer on your drill, because liquid rubber is thick and gooey, and it takes a lot of mixing to get the catalyst fully blended in. What happened to me was, I was standing over the can, mixing away, when suddenly the can itself started twirling on the ground, creating a good-sized geyser of rubber. That’s how thick it is. So, wear old clothes, and make sure the can is on a non-slippery surface. Little insider tip.
Applying it was pretty easy, as it turned out. You have up to four hours working time. First, dip a brush into the mixed EPDM and cut-in around anything necessary. Then, pour the stuff onto the area you want to cover straight from the can. Take a squeegee (which you will have to toss afterwards) and spread it as best you can, and then use a good-sized paintbrush and smooth it level. You will have to toss the brush afterwards, too. Then, repeat the steps in the next area. Each gallon covers between 40 and 46 square feet, so it’s recommended you pencil in lines on the working area so you know how far to spread it. I found that helpful. You want a finished depth of about 20mm. I wasn’t working on completely level ground, but it still went OK for me.
EPDM is on and drying. Don’t walk on it for at least 12 hours! The seams show but are just as strong as the rest of the roof.
Dried EPDM now needs hot sun to fully cure. This takes weeks, and depends on the weather conditions. It will continue curing whenever the conditions are right.
Rubber-coated skylight base.
So there you have it! If I could have done this earlier, I would have. You do need warm, dry conditions, and fully dry materials. If your area (like mine) offers that rarely, then try to find a workshop or garage to do this in. It’s worth it, being that it’s relatively inexpensive, easy for a DIY-er, and should last years. Any rips or tears are extremely easy to fix with either EPDM caulk or uncured EPDM tape. Oh, and it comes in white and gray, too. Plus the company will special-order colors for you if that’s your thing. Good stuff. 🙂
I’m off now to hopefully finish painting the interior. More on that later. o/