Whether you need a roof replacement or repair, using a roof membrane is a smart decision. You might be wondering if using an underlayment is necessary. The truth is, there is no downside. Yes, it might be a little more of a financial investment but the benefits vastly outweigh the cost. With the right product, you can protect the roof base from significant damage and possible repair costs. Let’s take look at why membranes are such a good investment and which are best for your home.
Why You Should Use a Membrane or Underlayment
Underlayment is a waterproof or water resistant barrier that’s installed directly to your roof deck before the actual roof material is installed. Here are some good reasons to use underlayment:
- It provides protection for the roof deck before and during the installation process.
- It provides an extra barrier in case water penetrates through the roof or if a shingle blows off.
- It’s often required for fire ratings and to keep buildings up to code.
- It acts as secondary weather protection.
- It separates the roof deck from the shingle which prevents any interaction between resins in green lumber often uses in roof decks and the shingles.
Single Ply Membrane Roof Types
Single ply membrane comes in a few different varieties but they are all have some key things in common. They’re manufactured basically the same way in that they’re derived from various plastics that are turned into flat, flexible sheets. Each variety is factory-made under strict quality control for consistent performance. This type of underlayment has become more popular than older materials because they’re stronger, more flexible, and more durable.
As their name implies, they’re designed to be use as one layer and are typically glued or fastened over the insulation material. Another perk to using single ply is that it’s UV resistance is better than that of other products.
There are three different types of single-ply underlayment: thermoplastic polyolefin (TPO), polyvinyl chloride (PVC), and ethylene propylene diene monomer (EPDM).
If you’re considering EPDM rubber membrane for flat roof installation, here what you need to know. It’s commonly used for flat or low-slope buildings around the world. Ethylene and propylene are the two main ingredients and are derivatives of oil and natural gas. EPDM black rubber roof membrane is available in two thicknesses and widths ranging from 7.5 to fifty feet.
As far as PVC vs TPO membrane roofing materials, there are a few things to you should know. If you’re looking for single ply membrane flat roof installation, TPO and PVC are both good choices. The main difference is that PVC has been around a lot long and has been able to build a better reputation for reliability.
How are they similar? As far as performance as an effective flat roof membrane, TPO was designed to combine the benefits of PVC and EPDM without taking on any of the disadvantages. TPO and PVC are both made of thermoplastic materials. Plus, they’re both heat weldable and are better at preventing leaks than EPDM.
They’re also both considered a “green” material because they can lessen the need for air conditioning use. Because they’re white in color, they resist heat and UV rays which can keep you home cooler without needed to run the air conditioner as often. They’re also both resistance to chemicals, grease, and oil and are flexible enough to flex as the room moves.
Originally, TPO was supposed to be a superior material to PVC at a lower price. Because keeping it inexpensive was part of the goal, the quality of the product suffered initially. This inspired manufacturers like GAF to improve their formulas. A lot of studies have been done and there are some conflicting opinions but manufacturers who set out to make improvements were successful. Today, GAF underlayment is some of the best in the business.
As for PVC, it’s a great choice for roof membrane under shingles on flat or low-slope roofs. Why? Because these roofs are flat or close to being flat, any water that gets under the shingles tends to pool. Without a slope, there’s just no way for it to drain. PVC can tolerate pooled water and prevent leaking or rotting through the roof base.
PVC is one of the best roofing underlayment materials but it’s also the most expensive. It’s been around longer and is the longest lasting and most reliable of the three types we mentioned. It can go up to 15 years without needing to be replace. (It’s important to note that newer formulas of TPO may be able to last this long but they haven’t been around long enough to know for sure.)
Just as there are multiple roofing underlayment options, there are different companies that have an edge on the competition.
When it comes to PVC roofing membrane suppliers, consider an IB membrane. IB Roof Systems has solutions for both contractors and homeowners. As for TPO, GAF synthetic underlayment is some of the best product available. They’re the largest manufacturer in Northern America and have worked hard to bring TPO up to the standards it was originally meant to reach.
Whether you’re looking at installing synthetic roof underlayment or thinking about a membrane roof repair, it’s important to realize the importance of using the right membrane. The benefits of using underlayment are significant, whether you’re having a professional job done or planning do it yourself waterproof deck membrane installation. A new or repaired roof is a huge investment not only in what you’re paying out of pocket but also in the value it adds to your home. It pays to figure out what is the best underlayment for your project to make sure you’re doing the job right.