Owens Corning Titanium X30 Underlayment Installation

In this video, I’m going to show you how to install nail down underlayment for your tile roof.

What is Titanium X30 Underlayment?

Underlayment is a critical part of any tile system. Tile roofs rely a lot on underlayment to keep the roof waterproof. Tiles keep out 90, 95% of the water, but there’s still water that gets in through cracks, crevices and even soaks in through the tile. That’s why it’s critical to use a good quality underlayment and do a good methodical job when installing the underlayment.

In this video, we’re gonna be using Owens Corning Titanium X30. It’s a great hybrid underlayment that doesn’t tear easily. It’s thick and it has both synthetic and tar material in it, so it’s just a great underlayment. Now, there are other options out there, we prefer to use a self-adhered when possible, but if the budgets don’t allow, OC Titanium X30 is definitely a great option that will last you for years to come. Watch the video and I’ll show you exactly what details to take to make sure that your tile roof does not leak.

Cutting and Installing the First Layer of Underlayment

All right, so what we’ve done is we’ve cut our underlayment down to half a roll. Generally, these rolls are about 36 inches wide and it has a line in the center, to cut it down the middle. So we’ve utilized that line, cut it down the middle and we’re gonna install this prior to installing our drip edge. And once we install it, I think it’ll be clear on why, just for this example, we’re not gonna install the entire length of this roof. We’re just gonna be installing a sample piece. You don’t have to worry about nailing it down too much. Just a few pieces, tack it down and you’re good to go.

What Type of Nails to Use for Underlayment

Now to nail down this tile underlayment, we’re using a ring shank plastic round cap nail. This plastic cap acts as a washer to keep the underlayment tacked down. And the ring shank of this nail helps it grab and really help it from not pulling up.

How to Install Drip Edge

Alright, now that we’ve got our first layer of underlayment installed, we want to install the drip edge on top of this underlayment. Though this may seem unconventional there’s a reason behind why we’re doing this and I’ll explain to you later, cause we’re gonna come up with another layer of underlayment on top of this drip edge.

Now I’m gonna install this corner for you here and show you how we mark out our corner. One thing to know that this is a two by four drip edge, and we believe that this four inches coming up the roof plane, gives us a better waterproofing as it just overlaps great instead of using a two inch. I’m gonna use my metal snips just to mark this out.

All right, now that we got our drip edge cut, we’re ready to install it. It’s just like pretty much installing any other drip edge with a shingle roof or a tile roof. We wanna place nails every 10 to 12 inches, on this four inch. We wanna go pretty much in the middle or you can do a staggered pattern.

How to Install Underlayment Around a Skylight or Chimney

0:03:16.3: Now, one thing we wanna do before installing the entire field of underlayment is we’re actually come in in our curbs or whether you have a dormer or any type of really square penetration, it can be a chimney, skylight or dormer. We wanna come install a first layer of underlayment, and what we’re gonna do is cut this at a 45-degree angle going out. So that when we install our primary layer of underlayment, we’re gonna cut in the other direction to make sure seams don’t overlap. And we have a completely waterproof underlayment in place. (Watch the above video at 3:51 to see how the underlayment is cut and installed around a penetration.)

Install the Primary Layer of Underlayment Over the Drip Edge

All right, now that we’ve got our drip edge installed, we’re ready to install our primary layer of underlayment. So what we’re actually gonna do is bring a full sheet of underlayment and come on top of this drip edge, and that’s what actually is gonna act as our primary underlayment instead of this sacrificial piece that we put down here.

You can either tack it down on one side or kick it out. But being that it’s a small area, we’ll just do by hand. We’re gonna bring this up about a quarter to half inch from our drip edge up so that it’s not visible from the bottom.

Installing the Second Layer at the Skylight Opening

We’ve already installed our base layer of underlayment here, and we’ve cut it at a 45-degree angle coming up the roof. Now what we’re gonna do is we’re gonna bring our underlayment over, pass it about 8-10 inches, cut it, then make another slit on it. So now that we’ve got this cut, we’re gonna cut this at an angle going down so that our joints don’t overlap. So you can see what we’ve done, is we have one joint coming up in this direction. We have another joint coming down. Once we nail this, it’s gonna be impossible for any water to go in down. Because once the water comes down here, we’re gonna roll down and off our drip edge.

Installing Underlayment Around a Pipe

0:06:24.6: Now I wanna show you what we need to do when we come up to a pipe. Unlike other roofing systems, in tile roofs, we have to install flashing when we get to pipes with the underlayments. So we’re gonna install our first layer, then install the flashing on top of that. So the easy way to cut this is when you’re rolling this out, back roll it a little bit so you have some slack, bring it up to the pipe. You can either make an X or just cut out a small circle like this. And there you have it. Doesn’t need to be perfect. Doesn’t need to be tight. Now that we’ve got our base layer of underlayment installed, we’re just gonna install the pipe flashing on top of this. All right, now we have one last step in order to ensure this is waterproof. We’re gonna nail this down. Nailing patterns are extremely important. You don’t wanna nail here on the bottom, you wanna nail on the sides. And now we actually want to install another piece of underlayment on top of this to make sure that any water that’s coming down doesn’t get under this lip right here. You can see this lip is sitting on top of the the underlayment. We don’t want any water to get on here. So we’re just gonna install a piece of underlayment coming down, leaving the bottom exposed.

All right, you can see what we’ve done here is we haven’t installed any nails on this flashing itself. So just in case there’s any water that gets underneath the tile, it’s gonna be completely waterproof, it’s gonna roll off the bottom here and off our roof. Let me show you how it works. You can see there’s no chance of any water getting underneath this top edge.

Installing Underlayment On Rakes

The last thing I wanna show you is on our rake ends. What we wanna do is bring our underlayment over about two to three inches, and just tack it down lightly. Then what’s gonna happen is when we install our rake tile it’s gonna fully cover this and ensure that no water gets underneath this underlayment. So all you do is again, bring it over two to three inches, tack it down and call it a day.