Learning Center

FAQ: Can You Put New Roofing Shingles Over Existing Shingles?

Written by Zach Reece | Jul 1, 2024 11:41:47 PM

Are you thinking about taking care of your roof without spending too much on a complete replacement? You might want to add new shingles on top of the old ones! This is called reroofing. It is usually quick and does not cost as much, but is it the best move in every situation?

Many people ask if putting new shingles on old ones is a good idea. It's tempting to skip the trouble of ripping off the old roof, but there are pros and cons to think about.

You should look into reroofing, as we will talk about what parts you can use and what your home's structure can handle. This choice might change your house's longevity and its future resale value. This strategy might be the smart answer you need for your roofing problem.

Let's dig in!

How Shingles Work

Shingles are super important for keeping your roof safe from the weather. If you plan to put new shingles on top of old ones, it helps to know a bit about how they're made!

Shingles come in layers, and what they're made of really matters. Just to give you an example, organic asphalt shingles include parts like felt or wood, and fiberglass shingles are based on fiberglass mats. Both types are popular for adding new layers to roofs because they're light, easy to put up and don't cost too much.

You have a few choices, like asphalt shingles, metal roofs, and roll roofing. Asphalt shingles, like the 3-tab or architectural kinds, are usually picked for layering. 3-tab shingles are thinner and lighter - which makes them easy to stack on existing roofs. Architectural shingles are thicker and tougher, so they last longer and look a bit like old-school parts like slate or wood. They adapt well to being put over other shingles because they're so flexible and strong.

Switching to metal roofing or roll roofing is different and will need a unique strategy. Metal roofs are heavier, and you will usually have to take off the old roof first. Your house needs this to handle the weight. Roll roofing looks like an easy and cheap option, but it doesn't last as long and isn't as protective as shingles or metal.

Roof longevity and maintenance needs are big deals, too. Shingles can last 20 to 40 years, so you can even recycle them! Poor installation, like layering new shingles over damaged ones, can lead to bumps and places where water collects, and that can mess up the whole roof.

Installing shingles is pretty easy. You start from the bottom of the roof and work your way up, overlapping them to make sure no water gets through. This strategy is easy and also cuts down on how much you'll spend on labor, and that makes shingles a budget-friendly choice for lots of people. Shingles come in lots of colors and styles, so you can match them to how your house looks without giving up any protection or lasting power.

Can You Overlay Roof Shingles?

Sure, you can put new roof shingles over the old ones sometimes! It's important to know when this is a good idea and when it might not be the best choice. This strategy is called a nail-over reroof, and that means you're installing new asphalt shingles right on top of the existing ones.

First things first, you should check that your roof is in good shape. The old shingles should be flat, sticking well, and not damaged or worn out. You need to sort out any shingles that are curling up, missing, or have a bunch of moss or algae first. Also, your old shingles should preferably be asphalt because other types might not work well with this overlay strategy.

Next up, you have to look into your local building codes. Different places have their own rules about roofs, and you don't want to break any laws or run into safety issues. These codes might even limit how many layers of shingles your roof can have. Usually, not more than two layers are allowed, mainly because of fire risks and the extra weight.

The extra layer adds more load to your roof's structure, and it is super important to have a professional check if your roof can handle it without any risk to your house's safety.

Something else to think about is that layering shingles could make it difficult to fix roof problems later on. It is tougher to spot and get to issues when there's an extra layer. You might save some cash initially on things like removal costs and dumping fees, but it might lower your home's resale value down the line. Possible buyers could worry that the roof will need a big fix soon.

Adding new shingles on top of old ones might mean you lose your warranty. Most shingle makers need a correct install, and that includes getting rid of the old layers to keep the warranty valid. It's definitely something to check before you choose to overlay.

It's a great idea to talk to a roofing expert who can help you make sense of the building codes, check your roof's condition, and guide you through the whole process.

Steps Before Reroofing

Start by really taking a good look at what you're working with before you even think about just slapping new shingles on top of the old ones. You should get an expert to give your roof a complete inspection - they will look for any hidden problems like serious damage or mold. These issues aren't always obvious but can cause big trouble if ignored. The expert will also make sure your roof isn't holding any unwanted moisture, and you definitely don't want that trapped under your new shingles because it could lead to more rot or mold!

It's important to see if your latest roof setup can handle another layer. If things don't line up right or seal properly, you might end up dealing with leaks down the line. Adding new shingles should help with your roof and not create new problems.

Everything needs to be looked at, and your roof should be ready to handle the reroofing, but there's some prep work you need to do. You should start by cleaning any musk and moss. You need to remove the old ridge and hip coverings because they won't match up with your new shingles.

Metal flashing is important for keeping water out. If yours looks old or rusty, you should replace it now to save yourself a lot of headaches later. You also need to pull those vents and pipes sticking out of your roof and either put them back or get new ones to keep the roof's surface smooth.

You also need to check the base layers of your roof - any weak places need to be fixed before laying down new parts. In really cold or wet areas, adding an ice and water barrier is a great idea, acting as extra insurance against water sneaking under your shingles.

Lastly, you need to keep local building codes in mind. Every place has its own rules about roofing, so staying within the law means no trouble later on. Whatever you're doing with your shingles must follow these guidelines and that will keep your roof safe and sound and make sure you're up to code.

Choose the Right Contractor

When it comes to adding new roofing shingles over the old ones, you really need to choose the right contractor. This job will take careful handling and a lot of skill, so it's important to hire someone who knows reroofing inside out. Overlaying shingles means checking the old roof's condition and figuring out if the structure can hold the extra weight. It also needs the right alignment and fastening of the new shingles to avoid future headaches like leaks or losing shingles.

First, you should do your homework closely when searching for a contractor. Check their licenses to make sure they can legally work in your area. You can usually do this on your state's professional licensing board or local government website. Next, make sure to check their insurance details. A good contractor will have both workers' compensation and liability insurance, meaning you're covered if any accidents happen during the work.

It's really important to check the quality of the contractor's previous work. Look at online reviews and ratings on sites like Google, Yelp, or industry-specific websites. Ask them for referrals or to show you some of the work they've done before so that you can see their skill level and commitment to doing a good job.

You need to look closely at the price and contract details. It's smart to get quotes from a few contractors to compare prices and what each contractor includes in their proposed scope of work. Sometimes, a low price can mean they're cutting corners, and that could cost you more eventually. When you choose a contractor, make sure everything is written in the contract, from the work that will be done and the parts used to the payment terms and warranty.

Finally, make sure the contractor has experience with the specific type of roof and shingles you have. Each roof has its own quirks, and a contractor close to yours is more likely to do a great job. Their experience also means they'll be better at anticipating and handling any possible issues that could come up during the project!

Installation Process and Best Practices

First things first, give the roof a good clean! Remove things like leaves and dirt to prevent issues with how the new shingles stick and line up. Then, take off any ridge caps and things like air vents or pipe flashing and put these back on later.

Have a look and fix any damage underneath before laying the new shingles. Patch up any torn underlayment or busted wood sheathing, as this will make sure your roof won't have problems later and create a solid base for the new shingles. Also, add an ice and water barrier if you live in an area with tough weather, as this step stops water from sneaking in and causing major issues down the line.

Next comes flashing - super important for keeping your roof in great shape by directing water away from possible leak places. Carefully fit new flashing around your chimney, in the valleys, and along the edges to keep your roof watertight.

Picking the right nails is also important. Use one 3/4-inch roofing nails for adding new layers, as these nails will grip through the new shingle into the old layer below, creating a strong hold that won't budge even when it's windy.

Pay extra attention when installing valley flashing because it needs to handle important water flow. To start shingling, create the starter shingles at the eaves since getting this right is important as it dictates how the rest of the shingles will line up.

As you lay the new shingles, make sure each row is perfectly aligned for a great look and a snug fit. Plan their overlap to keep water out and strengthen the roof against wind.

Protect The Roof Over Your Head

As we finish up our talk, let's not forget that reroofing might be quick and less expensive, but it isn't always the best choice. You should look at everything, from the state of your latest shingles to what your local building codes say. Does your roof have the strength to handle another layer? Thinking about these things is important because they affect whether you can go ahead with putting new shingles on top of old ones and how well they'll work out in the long run.

This isn't a decision to rush into, so take your time.

Your next big step, once you choose to reroof, is to choose the right contractor. The skill and reliability of your contractor will majorly change how long and how well your roof holds up. Do you feel good about picking a contractor for this important job?

At Colony Roofers, we understand the ins and outs of reroofing for homes and businesses alike. We mainly work out of Georgia, Florida, and Texas, and we're committed to providing great service that is professional and knowledgeable. We have free inspections that might be just what you need to choose wisely about your roof and protect your place. Why risk your security and investment? Our team is ready to make sure your roof is strong!

Contact us today and let Colony Roofers manage your roofing with the care and excellence you expect.