When it comes to the roofing industry, many contractors and homeowners focus solely on the shingles being used
Yet, there are so many more components to a roofing job that often get overlooked, like roofing underlayments.
Just recently, Roofing Insights co-host Brent Simmons examined the different types of nails that contractors use when performing roof installations.
Now, Simmons and Roofing Insights are diving into the oft-forgotten subject of underlayment, the goal being to inform homeowners of one more aspect of the roof installation process.
Keep reading to learn about the different types of roofing underlayments and which one is best for your home!
Before examining the specific types of underlayment, it is imperative that as a homeowner you understand what exactly underlayment does for your home.
According to Simmons, underlayment simply serves to protect your home from water that the shingles situated above it cannot capture.
“Underlayments are basically what the name implies,”
says Simmons.
“It’s an underlayment for the final roofing product.”
“They go between the shingles and the roof deck. This is a second layer of protection for if something were to happen to the shingles.”
Real quick: there are five different types of underlayments.
Keep scrolling to learn more about each type of underlayment.
1. Asphalt/felt/tar paper
“There are a ton of different names for them, but this is one of the oldest forms of underlayment that’s still around,”
Simmons says of asphalt, felt, and tar paper.
This type of underlayment is made out of wood pulp and other organic materials, which acts as paper that is coated with an asphalt layer on top of it.
“What the asphalt does is it actually helps the water shed off so the roof doesn’t absorb water, but you are not going to see a lot of roofing companies install these products,”
explains Simmons.
The reason for this is because this type of underlayment has been replaced by a more efficient product, which brings us to underlayment number two…
2. Synthetic felt
This is a polypropylene synthetic membrane. It serves the same purpose as tar paper and asphalt underlayment.
Synthetic felt is considerably larger than felt paper, but with added benefits like strength and durability, the benefits of installing synthetic felt underlayment are noticeable.
“You will find these underlayments on every single roof, or at least you should be finding them there,”
Simmons says of the synthetic felt.
3. Ice and water shield
This kind of underlayment is a unique product that has a plastic layer which protects the backside of the underlayment, which is useful for roofs that have more complex designs.
“The purpose of this underlayment is to actually go in areas that are more prone to leaking, so in the valleys of roofs, around chimneys, and end walls where the roof meets the wall,”
says Simmons.
“That’s where you’re supposed to put this underlayment. What’s so cool about it is that when it heats up it will stick to the decking really well, making it almost impossible to remove. Any nails that get driven through this product will actually seal around it when it gets hot.”
4. High-temp ice and water shield
You already know about the standard ice and water shield underlayment, but manufacturers have also designed an upgraded version that is still gaining traction in the roofing industry.
This product is actually so new to the market, that Simmons says he has not yet seen it installed on a roof.
“It almost looks like synthetic felt on the surface, but you still have that sticky backing,”
Simmons says while examining the product, adding that the high-temp ice and water shield was designed for specific climates.
“You are supposed to use this in areas where it gets extremely hot, like under metal roofs, copper roofs, and standing seam.”
The high-temp ice and water underlayment is also compatible with synthetic tiles, clay tiles, and concrete tiles.
5. Base sheet
The last type of underlayments are base sheets.
They are part of rolled roofing systems, which are granulated flat roofs that you usually see on very low-pitched roofs.
In these instances, base sheets are installed before putting on the granulated caps sheet.
This product also has markings on it so you can determine the spacing on the cap.
“Base sheets are similar to ice and water shield because you have a sticky backing. It’s quite a bit thicker as well,”
says Simmons.
There are many other underlayment products on the market, but Simmons and Roofing Insights have found the five in this list to be the most common.
If you know of any other types of underlayments currently on the market, let Simmons and Roofing Insights know in the comment section below!
And before you go, don’t forget to subscribe to all of Roofing Insights’ social media channels so you never miss any of their upcoming content!
I understand that some newer synthetic underlayments also provide a radiant barrier function. If that is true can you tell us more on how to reduce the heat in the attic.
Very good info I needed when dealing with a roofer who replaced most of damaged roof in 2017 w 10 yr warranty and we have had to call several times over the years as most recently as last weekend, we still have the leak coming into our living room that started the whole problem in Sept 2017 our insurer sent several adjusters the last one was who the insurer used- most detailed of damage to roof and inside of house downstairs. and realized we had hail damage and roofer also pointed it out.
Now roofing company hired a project mgr sometime ago who was not part of this owner’s team when we had the work done. We dealt directly with the owner of his company. Project manager is now saying that they don’t know where the leak is coming from and gave us a so called “estimate” yesterday with no details but total cost of $3000 plus tax. I was truly surprised he should have had line item breakdown by material costs and labor as I told my husband to tell him. (I spent my 35+yr career as a cost analyst for both GE Aircraft Engines & federal gov’t agencies DOE (Dept of Energy & DOD, so I know that much at least. Project mgr is refusing to do this and told my husband last night that he would split the cost in half and that was it. I find this extremely unprofessional and quite frankly BS. We live in the SW in NM. We had a wicked rain and snow storm after Christmas and leak started coming into my living room ceiling as it did initially in 2017 and afterwards previously post-new roof that took 2 days to complete originally.
The project mgr had employees on our roof checking out couple days ago and had them remove tiles(were new in 2017) which are not damaged. We do not think they put them back, my husband has to get up there today to check. This new estimate to repair is almost as much as we originally paid and it is for a much smaller area this was the original area of leaking. AND previous revisits we got no paperwork after the so called “repair” and the owner was not even aware they came out to fix prior leak (or should I say not fixed)
The estimate does not even provide square footage to be fixed or estimated amount of material needed pretty vague. I will show below exactly what this new estimate says. What is the point of this 10 YR WARRANTY IF NOT BEING HONORED? Not sure how to proceed with this anymore. Just getting too much pushback. Any suggestions? would be greatly appreciated. My big concern is the vagueness of material he mentions in the estimate. the underlayment for wind water protection.
THE ESTIMATE:
“Remove and replace approximately 150 damaged tiles (tile color may
not match due to age)
• Inspect decking where leaks were indicated by homeowner, near
skylights and pipes
• Replace decking if needed
• Install water shield underlayment areas where leaking has been
indicated by homeowner
• New mortar around skylights and pipes in indicated area
$3,000.00
Tax $225.00
Total $3,225.00”
may be covered, but not all of the other aspects of your roof, such as gutters, vents, underlayment, etc. Always read the warranty thoroughly before signing anything, so you don’t get surprised