Although you may not spend much time thinking about what’s under the layer of shingles on your roof, it’s important to familiarize yourself a bit with roofing techniques and materials before hiring a roofing contractor. This can help you keep track of the installation process and ensure you’re pleased with the end result.
Here are four basics you should know about underlayment before you choose a roofing contractor.
1. Underlayment Types
The types of underlayment typically used for asphalt roofing are tar paper and synthetic underlayment. Tar paper is basically a felt paper material impregnated with tar, although composition can vary by product. Tar paper protects the roof deck during installation and helps the roof shed any moisture that gets past the shingles.
The right underlayment can also add fire resistance. And it can smooth over the edges of the boards on your roof deck so that their outlines don’t show through the shingles in an odd effect called picture framing. But it can’t make your roof 100 percent water and moisture proof. Waterproof underlayment can, but that’s typically not recommended for most roofs.
Waterproof underlayment is used for vulnerable spots such as roof valleys and around the edges of the roof to help prevent ice dam leaks. But it’s also a vapor barrier. So if you install it across your whole roof, moisture from the attic air is more likely to condense on the underside of the roof deck, which can cause rotting and mold.
2. Common Mistakes
Aside from using the wrong underlayment, common mistakes include incorrect installation, shingling over underlayment when wet, and accidental damage from walking on the underlayment.
Quality control is an important criterion when choosing a contractor. You’ll want to choose a contractor who prioritizes the quality of the work over the speed of the project; otherwise, problems are more likely to occur. A professional contractor will attach the tarpaper correctly or and pay attention to the underlayment details.
3. New Underlayment
Underlayment should be a non-optional part of the roofing process. For one thing, unless you want to void your manufacturer’s warranty, you need to follow their specifications for roofing installation technique and materials, and that includes installing the correct underlayment with the roof. And without underlayment, your roof could wear out and develop leaks more quickly.
4. Improved Protection
Your manufacturer’s specifications may say that your roof needs to have at least a certain thickness of roofing felt installed as underlayment. But if you want maximum protection, you may want to go for a slightly thicker product instead to provide superior protection.
Thicker felt gives better protection against any water that makes it through the roof. And any storm damage, such as a missing shingle, will be less likely to create a leak before you can get it fixed because thicker tarpaper will provide slightly better resistance against UV damage.
Different types of roofing have different underlayment needs because they function differently. Concrete tile roofs shed the majority of water, but some can reach the underlayment. If the underlayment isn’t up to the task of shedding off that much water, the roof could spring multiple leaks relatively quickly. That’s why the choice of underlayment is so important.
These are some of the basics you should know about underlayment before hiring a roofer. When reading through proposals from roofing contractors, check for what they plan to do about underlayment. Their plan should specifically mention tearing off the old underlayment and putting on new underlayment. And you can check to see what type they plan to use as well.
When you’re looking for an all-new roof, Cloise & Mike Construction, Inc., can help. Get in touch now to learn about what types of roofs we work on or use our website to request a quote for your roofing job.