Options for Waterproofing a Flat Roof in Florida

Flat roofs have completely different needs from traditional shingle roofs. While the biggest problem for shingle roofs is wind, flat roofs are much more concerned with water damage and leaks. That’s why, when planning a flat roof replacement, installing a waterproof roof is essential.

But what’s the best material to waterproof your flat roofing system? We’re PITCH Roofing, and as your local roofing partner, we’re the flat roofing experts you can trust. Keep reading to see everything you need to know about your options when it comes to waterproof flat roofing systems!

Why Do Flat Roofs Need to Be Waterproof?

Before we get into your options for a waterproof roof, let’s talk about why water is such a concern for flat roofs. While we call these systems flat, they aren’t technically straight lines. Rather, they’re low-slope roofs: roofing systems that are only slightly tilted. In theory, this should allow water to drain easily off your roof.

In practice, however, things are a little more complicated. There are many ways for water to become trapped on a flat roof. Storm debris, problems during installation, and degradation of your roof can all lead to water ponding on top of your structure. When this happens, having a waterproof roof is essential to keeping water out of your roofing system.

For Floridians, our rainy season is no joke. Showers are a near-daily occurrence during the summer months. To make sure you don’t develop any leaks, having a waterproof roof is nothing less than essential. Now that we’ve covered the need for waterproof flat roofs, let’s talk a bit more about your roof replacement options.

Your 3 Options for a Waterproof Flat Roof

While the goal of a flat roof is clear, there are many different ways to achieve this. Each option has pros and cons, but for our money, some waterproof roofing materials are better than others. Let’s take a look at the good and bad of each option!

Modified Bitumen

When looking for a budget-friendly waterproof roof, modified bitumen is a popular choice. Made from rubberized asphalt, these roofs combine the durability of asphalt with the water-resistance and flexibility of rubber. The combination offers a lot of advantages when resisting Florida’s unpredictable weather!

Some of the biggest advantages of modified bitumen roofing include:

• Because this is a multi-ply roofing system, it’s better able to resist puncture damage than other materials.
• Mod bit roofs only cost $4 to $8 per square foot, making them one of the most affordable options for waterproofing a flat roof.
• Since modified bitumen roofs don’t have seams, they are at lower risk of developing a leak in the course of their lifetimes.
• Modified bitumen is durable enough to withstand regular foot traffic.

Modified bitumen isn’t a perfect roofing material, however. Like any other roofing system, it has its downsides. To help plan your roof replacement, let’s look at the cons of modified bitumen:

• Modified bitumen only lasts for 15 to 20 years, which is a shorter lifespan than other materials can offer.
• Because these are not rubber roofing systems, they can’t withstand standing water well. If water is trapped on your roof, modified bitumen will degrade fairly quickly.

TPO

TPO, thermoplastic polyolefin, is among the best waterproof roofs in Florida. Made from rubberized polymers, this is what’s commonly referred to as a rubber roof. Since rubber is highly resistant to water, it is among the best options for a waterproof roof.

Let’s take a look at the biggest pros of getting a TPO flat roof:

• As a rubber roof, TPO is extremely resistant to standing water.
• TPO usually comes in white. Combined with its protective polymers, this gives it increased UV resistance and helps cool your structure.
• TPO is generally considered affordable at $4 to $10 per square foot.
• Since it was invented in 1990 and has been reformulated several times, nobody is 100% sure how long a TPO roof will last. However, expert estimates put the lifespan of TPO between 20 and 30 years.

While these are all great benefits, it’s also important to be aware of the downsides of TPO roofing, including:

• TPO is vulnerable to extreme heat. These roofs expand and contract with the sun’s heat, which can gradually loosen your seams over time, potentially letting water into your roofing system.
• Some formulations of TPO are especially thin. Since this is a single-ply roofing system, these thin layers of TPO can be more vulnerable to puncture damage from storm debris and hail.

Liquid Waterproofing

Unlike other options on this list, liquid waterproofing is not a true roofing system. Rather, it’s a coating that you apply on top of an existing flat roof. The idea behind this is to improve the water resistance of your roof without having to invest in costly roof replacements or repairs.

The advantages of liquid waterproofing on a flat roof are:

• Because it’s applied as a liquid, this solution for a waterproof roof creates a tight seal on your roof that keeps out water.
• In addition to waterproofing, this material also improves your roof’s UV resistance and resistance to puncture damage.

While liquid waterproofing sounds great in theory, it has more than its fair share of downsides. Here’s what you need to know about the cons of liquid waterproofing on a flat roof:

• If there is any moisture on your roof when liquid waterproofing is applied, that liquid will be trapped inside your roof. This can lead to mold, rot, and even a structural failure of your roofing system.
• Applying liquid waterproofing is very tricky. If your installers make even a small error, it can reflect in the patterning on your roof, which can lower your structure’s curb appeal.
• Liquid waterproofing needs a smooth surface to properly adhere. This may not be the case with your roof, especially if it’s an older roofing system or modified bitumen.
• Unlike other materials, liquid waterproofing is not a roofing system in and of itself. Some people get confused on this, which can make them confuse it for a roof replacement and neglect the needs of their structure, such as replacing damaged decking.

Get a Free Flat Roofing Estimate

In Florida, you have plenty of options for getting a waterproof roof. It’s all about finding the right fit for you. No matter what you decide, you can count on the experienced professionals at PITCH to do a great job installing your new, waterproof flat roof. Getting help from our team starts with your free, no-obligation roofing quote!

To get your free flat roof estimate, call us at 727-677-4824 or schedule your estimate online. We’ll inspect and measure your roof, have a quick chat about what you’re looking for, and then prepare an itemized quote that covers the full cost of getting you a waterproof flat roof. You can even sign up for an online-only estimate to skip the in-person roof inspection! With this method, we use satellite images to virtually measure your property and save you time.

No matter what kind of flat roofing system you’re looking for, you can count on PITCH Roofing to install it. With deep roots in the community, our crew is made up of local roofers you can count on. When you reach out to our friendly team, you’ll see why Floridians keep coming back for our tried and true style of roofing done right!