Using Peel-And-Stick Self Adhesive Underlayment for Roofing


Let’s depart slightly from the world of design and pretty today to talk about the more functional (and arguably as important) side of your house. Let’s talk about roofing.

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I’m writing this post from my truck in front of a roofing job we’re doing today. When this job is done, if you look at it from the ground, there won’t be anything remarkable. It will just look like another shingle roof. But there are two special things about this roof. Things that won’t really show any value right away. Unless we have a hurricane tomorrow that is.


Using Peel And Stick Underlayment Makes A Better Roof

Until recently, all shingle roofs had the same type of underlayment. They all used rolled asphalt/felt material commonly referred to as “tar paper”. The only way to improve the quality of the underlayment was to make it thicker or add another layer. You may have heard of 15 pound felt and 30 pound felt, the two most common thicknesses of that material.

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But on this job, and most jobs we do now, we’re using a newer product that is really much better. We’re using a material that is not only thicker, but has an adhesive applied to the back at the factory. You peel off the backing as the material is rolled out, and stick it on. Like a giant roll of duct tape! (And we all know that duct tape fixes anything)

Two-Fold Advantage of Self-Adhesive Underlayment

The problems we experienced with the old method of using a felt underlayment came at two points in the life of the roof (only one for most roofs).

  1. During Installation – When a roof is replaced completely (rather than roof-over) the house is exposed to the elements for some time. Depending on the size of the house and the roofing crew this could be anywhere from a few hours to a few days or even weeks. The rolled felt would fail during this time as a result of either or both of the following problems:
    • Being torn and worn-out by traffic on the roof (the crew)
    • A medium to strong wind event tearing the paper off
  2. Serious Windstorm – Once the shingles are installed, the roof is generally water tight and secure. At that point the underlayment is a “secondary” barrier for any small amount of water that might find its way through the shingles. But in the event of a serious windstorm, such as a tornado or hurricane, the shingles often blow off. With a felt underlayment, both layers blow off and the wood deck is exposed. This is the cause of a large portion of the loss in a hurricane. Water just pours in.

Peel-And-Stick Sticks

Peel and stick underlayment is stuck to the plywood with a strong adhesive on every square inch of the surface. In all but the most severe conditions, it stays down. Once the adhesive has set, it’s very difficult to remove even intentionally.

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In the above photo you can see the white backing that has been removed from the underlayment. You’ll also notice the lack of nails that you would see with rolled asphalt/felt.

This strength goes great lengths to resolve both of the above concerns. A roof with this type of underlayment could be left at the “dry-in” stage for weeks or months without leaking (thought this is not a permanent roof alone – it can’t stand-up to the sun). Foot traffic doesn’t do as much damage and windstorms are considerably less of a concern.

So much so that many insurance companies will offer a substantial discount if your home has a properly installed peel-and-stick (self-adhesive) underlayment.

It’s worth it.

50 Year Shingles

I said there were two things about this roof that were special. The other is the thickness of the shingles themselves. On this particular job we’re using a top-of-the-line 50 year shingle from Tamko.

Between the two upgrades, the roof we’re putting on today is significantly better and worth the extra cost.

Comments

  1. Lizzie says

    I have a dumb question…I have a very leaky 30 year old mobile home that we are renovating. What is the difference between this peel and stick underlayment and peel and stick roofing? Would the underlayment act in the same way if we kool sealed afterwards? I am trying to justify the cost difference, and I want to make sure I am not just putting a bandaid on the place :)
    Thanks for your help- and knowledge.

  2. Christine La Coursiere says

    Do you have an suggestions on the difference of applying the peel and stick underlayment vs. asphalt/felt? I help manage a roofing company and the new guys have not used it before. We had a guy slide off the other day. They said it’s slippery, I have a feeling something isn’t being done right.

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  1. [...] this clears up the question of self-adhering, peel and stick, secondary water barrier underlayment.Last week I had several folks ask me what I was referring to when I mentioned self-adhering underlay…t-weight: normal">re-roof and roof install estimates.  They wanted to know just what it was and [...]