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8 Common Ways A Roof Replacement Goes Wrong, Even with Experience

When it comes time to invest in a roof replacement, research is a homeowner’s best friend. But once you start digging into all the different aspects of the project—materials, warranties, costs, ventilation, etc.—research can become overwhelming.

Finding a roof replacement contractor that you trust is as important as the individual components of the project. Doing your homework to find the best partner for the project can ensure every other decision is an effective one.

The problem is that many homeowners struggle to differentiate between roof replacement contractors.

Still, choosing the right contractor can be all the difference between a successful project and one marred by common mistakes. As you work through the planning process, keep these 8 mistakes in mind that even the most experienced roofers can make.

1. Failing to Use Starter Strips

No roof replacement should be done without an underlying starter layer of adhesive strips. Without starter strips, you have to install shingles directly to the frame, leaving the roof susceptible to wind and other elements.

Your roof is supposed to last you decades. Don’t let a simple step like starter strips result in shingles blowing off just a few months or years into the roof’s lifespan.

2. Skipping the Ice and Water Shield

For years now, sealing roof eaves during replacements with ice and water shield has been a standard practice. However, “old-school” contractors may opt for more traditional underlayment.

You want to be sure that your roof replacement contractor is installing ice and water shield in vulnerable areas, especially in a wet climate like Maryland. Without it, you may be at greater risk of seeing leaks and water damage.

3. Relying on Low-Quality Pipe Collars

Rooftop vents are essential for filtering gas out of your kitchen and bathrooms. However, ventilation pipes have become common components to blame for rooftop leaks.

That’s because many roof replacement contractors install collars around the bases of these pipes that aren’t suited for a long lifespan. Aside from rapid wear-and-tear, contractors can make mistakes when cutting collars to size. Even a slight miscalculation can lead to cracks that expand over time and let more water under the roofing materials.

4. Trusting Caulking for Water Resistance

In many renovations, contractors trust caulking to create waterproof seals. Whether it’s around windows, doors, in kitchens, or in bathrooms, caulking is a must-have for just about any project.

However, roof replacement contractors often make the mistake of trusting caulking for water resistance. Caulking will shrink and expand as weather changes, leading to cracks over time. These cracks will let water seep into the roof and cause further damage.

It’s better to trust a proper flashing system coupled with a true waterproof/resistant underlayment and flashing for protection against the elements.

5. Adding Layers in the Wrong Order

For most homeowners, a roof replacement may seem like it’s all about the shingles. However, there’s much more to the project than just the top layer.

Every roof replacement contractor knows the layers necessary for success. But a common mistake is to add a layer out of order, compromising overall protection.

Generally, the order should start with the eave and move to the drip edge, followed by ice/water guard and underlayment. Then, contractors should add flashing, shingles, and ventilation.

6. Overdoing the Flashing

Step flashing has become a common technique for improving water resistance across a new roof. This process includes a woven installation of flashing and shingles rather than a more traditional layered approach.

The only problem is that some contractors will go overboard during installation. Some contractors may make mistakes trying to weave flashing and shingles together. Others may nail flashing to both walls and the roof deck. Both missteps can create gaps in what was supposed to be a water-tight seal.

7. Using the Wrong Fastener Length

It may seem obvious, but the nails used to fasten shingles to your roof deck must be the proper length.

During busy seasons, contractors may get caught up between projects and make a mistake by using fasteners that are just too short. This results in loose shingles that either blow off in the wind or allow water to seep into the home. Either way, it’s something you (and your contractor) want to avoid.

8. Neglecting the Roof Deck

Decking acts as the foundation for your roof replacement. If it’s weak, the quality of installation won’t matter because your entire roof could be compromised.

Roof replacement contractors may overlook deficiencies of existing decking, moving forward with the foundation rather than building a new one. You may save money this way in the short-term, but overall, you’ll end up with a sub-par roof replacement.

Make sure any roof replacement contractors properly inspect the decking to decide whether it needs to be replaced as well.

Finding a Roof Replacement Contractor You Trust

Unfortunately, too many homeowners discover their contractors made these mistakes after the fact. It’s not as if a potential partner will come out and explain all the mistakes they’ve made in the past.

That’s why it is important to be vigilant in the research phase. Be picky and ask a lot of questions before choosing a roof replacement contractor. And remember, the best contractors will take steps to understand everything about your project, inspecting the roof and working with you to determine your true needs.