4 Common Problems With Synthetic Roof Underlayment

Whenever you get a new roof installed, you must be proactive to ensure that every part is installed properly. And then there’s the age-old argument of what type of roof you want. However, homeowners rarely focus on some of the foundational parts of a roof, like the roof underlayment.

Synthetic roof underlayment is generally considered the best option for all roofs as long as it’s in accordance with your local building codes. That being said, this doesn’t mean that it has no drawbacks. In fact, while the benefits are much more significant, a few cons might make you reconsider getting a synthetic over a felt underlayment.

So, today, we’ll take a look at some of the problems with synthetic roof underlayment. But first, let’s actually dive deeper into what a synthetic underlayment is and why it’s necessary for any roof.

Synthetic Roof Underlayment

What Is Synthetic Roof Underlayment

Synthetic underlayment is basically layers of plastic mixtures that are placed on top of your decking. These mixes are usually made of polyethylene and laminated polypropylene. This synthetic mixture excels at moisture protection, as it doesn’t absorb water, making it a great material for roof underlayment.

Is Synthetic Roof Underlayment Necessary

In general, having some form of roof underlayment is a necessity, regardless of your roof type. These prevent moisture from penetrating your roof and add to the house’s sound and heat insulation.

Now, as for whether a synthetic underlayment is necessary or not, the answer is simple. It’s up to you. That’s why we’ll cover some of its problems below so that you can make a more informed decision.

The Most Common Problems With Synthetic Roof Underlayment

Once again, we want to note that synthetic underlayments are probably the best option in the market. Then again, so are slate roofs, but very few homeowners want to invest that much money on their roofs.

That being said, here are some of the shortcomings of this underlayment type.

1. It’s Costly Compared To Other Roof Underlayment Options

A felt roof underlayment will generally last as long as an asphalt shingle roof, between 20-30 years. With synthetic underlayments lasting a decade (or more) longer than that, it goes without saying that they are also more costly.

However, the price difference is pretty significant when taken at face value. A plastic underlayment will cost almost 3 times more than a felt one, which might seem like a pretty bad deal.

In reality, though, with most average-sized roofs, the difference will only come out to a few hundred bucks. So, if you’re going the extra mile to get a metal roof that’ll last longer, spending a bit more on the underlayment won’t be as significant.

2. Some Building Codes Prohibit the Use of Synthetic Roof Underlayment

One of the most common reasons why homeowners don’t opt for synthetic underlayments is building codes. Each state has different laws, with each local government having its own. So you’ll have to consult your local roofing company to ensure that you can have synthetic underlayment installed.

You’ll have to be extra careful with this, as you’ll get in trouble if you end up installing one when local building codes prohibit it. In this case, you’ll have to go for a felt underlayment and hope for the best.

3. Inconsistent Quality and Thickness

With synthetic roof underlayment being so popular, many manufacturers provide an inconsistent product or blatantly lie about it. In general, one of the factors that you have to look out for is the weight of the underlayment, as heavier usually means better.

At the same time, some companies brag about the thickness of their underlayment, which doesn’t actually translate to extra durability (or weight, for that matter).

This extra thickness is achieved by adding a top layer to ease walkability, which doesn’t provide any further moisture resistance. So, you’ll have to be careful and do your research when you purchase your underlayment.

4. Challenging To Remove

A big chunk of synthetic underlayment on the market is peel and stick. This is notorious for being extremely difficult to remove once attached to the decking. In turn, when the time comes to replace your roof underlayment, you’ll usually have to remove the entire decking as well.

There are, of course, some that can be easily removed, but they come at a premium. If you ask us, it’s definitely worth spending the extra bucks, as it’ll save you more in the long run.

Let Us Pick Your Roof Underlayment, the Wise Way

Generally speaking, we always suggest you opt for synthetic roof underlayment as long as you properly maintain it. The extra durability and longevity it comes with significantly outweigh the drawbacks you might face with one. So, if you’re in SoCal and require an underlayment change, look no further than us.

At Roofing Wise, we strive to make roofing more comprehensible for everyone the wise way. Call us now at (833) 315-7663 for a free estimate!

Scroll to Top