“Time is Money” 

Or so the saying goes. 

And when it comes to installing a new roof, saving time is top of mind for both homeowners and contractors. 

After all, who wants the sound of a nail gun echoing off their roof for any longer than they need to? And for contractors, installing a new roof quickly means reducing the risk unpredictable weather might pose. 

This commitment to timeliness has benefited the construction world in many ways. 

Before the invention of asphalt shingles, composite shingles were all the rage. These shingles were made of felted fabric covered in tar and their installation process took 3-5x what it takes for a modern roof. 

In response, the first asphalt shingles were designed.

“Time” is a big motivation for innovation in the construction industry.  

When vinyl siding was first invented, it was advertised as cheaper and easier to install than aluminum siding. 

The invention of gutter guards saves homeowners time on exterior home maintenance. 

The truth is everyone loves saving time, and there’s nothing wrong with that! 

But at what point does ‘saving time’ become cutting corners? 

Let’s talk about that today with this question:

Can you skip the tear off on your new roof…and just lay new shingles over old shingles?

What Happens When You Layer Asphalt Shingles 

Asphalt shingle roof

This installation “trick” is exactly what it sounds like. Instead of removing the pre-existing shingles, a second new layer is installed on top. 

Some contractors view this as an impressive show of workmanship. They will tell you that lining up shingles over shingles is a difficult job, and blending the two into one roof while making it look good isn’t easy.

But professional contractors- our team included- refuse to layer shingles. Removing shingles can be a hard and tiring job, but the risks of layering outweigh the time saved. In the end, it’s more important to us that we leave a jobsite knowing we can stand by the warranty we offer. 

Still, while you’ve collected bids for your new roof, you may have run into this option. So let’s take a closer look at the “pros” and cons of layering shingles. 

The Case For Multiple Layers

2 layers of asphalt shingles

Tearing off shingles seems like an extra step to some homeowners. And we get it- when your home is without a roof? The less time spent on replacing it, the better. You want protection, and you need it fast!

Not to mention you’ll be saving money during the initial installation. By skipping this step, you’re cutting back on labor costs on the extra day of tear down. 

Installing shingles over shingles can save you money in the short term. 

But how much time are you really saving? At most, it takes 3 days to remove old asphalt shingles. Our crew can take care of 95% of our clients’ tear off in less than a day. That’s it!

You might be thinking:

 “Well, layering shingles is less invasive than tearing everything off. I don’t want a crew hanging around my house for a week…”

But when you choose a crew that’s committed to providing a clean, respectful worksite (like us!) run by a contractor who prides himself on quality installation…why, that type of thinking won’t even enter your mind. 

(We often receive questions from homeowners about the installation and what to expect. We discuss prep for your new roof and other common questions here.) 

If the only argument in favor of layering shingles is saving a little time, what’s the argument against it? 

We Won’t Install Shingles Over Shingles. Here’s Why:

Top of house and roof

Two roofs aren’t better than one. 

You’d never install one roof over another but when you layer shingles, you’re doing exactly that! 

And this double roof installation causes many problems.

The biggest? The way your double-layered roof traps heat.  

When installing shingles over pre-existing shingles, you’re creating extra insulation.

We recently covered attic ventilation and the importance of keeping your roof cool. Here’s a quick refresh: 

Summer heat is one of the most dangerous risks for your roof. When improperly ventilated, that heat begins to melt away and destroy your shingles. Overtime as the shingles contract and change shape, damaged areas leave room for water to get in. 

When you stack shingles, you’re not allowing your roof to have proper air flow. In return, you’re overheating both your home and your roof. 

This imbalance costs you in two ways: 

  1. Trapped heat causes both sets of shingles to decompose, meaning you’ll need to replace your roof a lot sooner! Average asphalt shingles can last as long as 20 years, but when layered, that number can drop by 40%.
  2. Improper air flow affects your energy bill. Layered shingle roofs constrict air flow, which can increase your energy bill by up to 20%. 

The truth is, you’re not saving time or money in the long run. By layering shingles, you’re setting your roof up for failure. 

These aren’t the only downsides to layered shingles. Other problems include: 

    • Extra weight on your roof can damage your home’s structure.
    • Algae and bacteria become trapped and can continue to grow on the original shingles.
    • Reduced home value.

Layered shingles might seem like a great idea in the short term. But the negative effects of this installation style continues to outweigh the “benefits.” 

The Best Roof for Curb Appeal

Decaying layers of shingles

Did you know that installing a new roof has a return on investment as high as 68%? 

In fact, installing a new roof is one of the best things you can do when putting your house on the market. 

However, that same statistic doesn’t carry over to roofs with multiple layers. 

When a homebuyer starts the process of buying a home, the home insurance company inquires about the quality of the roof. The two biggest concerns are 

    • the age of the roof, 
    • and how many layers it has. 

Almost every insurance company will only insure the top layer of the home’s roof. What does that mean for the homeowner? 

If a storm hits and the roof is damaged, insurance will only cover a new top layer of shingles. You’ll have to cover damage expenses to both the original layer of shingles and the roof’s sheathing. 

For this reason, roofs with multiple layers of shingles are passed over by potential buyers.

Not planning on selling your home? Curb appeal still matters. 

From friends and neighbors to complete strangers, the front of your house is the first thing everyone sees. And although we shouldn’t make a snap judgement based on aesthetics alone, we do. 

You want a roof that looks like this: 

Healthy roof

Not this: 

Layered shingles

Your roof is your home’s strongest defense, and most powerful asset. Proper roof installation is the best way to care for your roof, and for your home. 

Time to Replace Your Shingles? 

Let us help you do the job right the first time. 

Your contractor should be dedicated to getting the job done right the first time. Here at Martin, we don’t cut corners. We believe that the best way to guarantee a healthy roof is through time and care. If you’re ready to replace your asphalt shingles, we’re here to help. 

Need help repairing a roof with layered shingles? Don’t worry- we can help with that, too. 

Give Vern a call at 570-345-0406 to start the conversation about your new roof.

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