Every homeowner knows what an investment a roof is. While a roof is a necessary investment, it can also be rather expensive. We understand that having to pay so much money is not always ideal. With an investment this big a lot of homeowners try to save money where possible. One of the ways they try to do this is by adding additional layers of shingles over their current asphalt roof. Some homeowners even try to do this while there are already two or three previous layers present.
This article will be addressing the question “Can you put multiple layers of shingles on a roof?”. While we will provide a clear answer to this question, we will also be sure to go over some warnings and additional information you should know before attempting to cover up your existing roof.
Can there be multiple layers of asphalt shingles on a roof?
To answer this question, no. Well, actually you can not have three or more layers of asphalt shingles on your roof. In many states, it is acceptable to have two layers, but that is the maximum. While there are rules and regulations in place, there are still plenty of homes out there that currently have three or more layers of asphalt shingles on their roof.
We at Liberty Roofworks strongly advise against nailing on more than two layers of asphalt shingles. As a company, we do not accept this type of work. Any reputable and respectable roofing company will also decline this type of work. Instead, it is recommended that a full roof replacement takes place. Ideally, your roof never gets to the point of having two layers of asphalt shingles, but we understand that sometimes it needs to be done. There are some situations where it is acceptable and possible to nail over an existing roof, but it isn’t too common. Most roofs actually will not be a great candidate for this.
If your roof is old and towards the end of its life but the shingles are all still flat and damage-free, then you can get away with nailing over your existing roof. The damage in question includes lifted or cracked shingles and any bumps. The reason most roofs are not a great candidate for a nail-over is that by the time their asphalt roof is at the end of its lifespan there tends to be at least some form of damage to the existing shingles. There are a few other requirements needed to potentially qualify for a nail-over. These requirements include a limited amount of flashing and penetrations. There should also be no walls that push against the existing shingles.
Even if you have your heart set on nailing over your first layer of asphalt shingles, it really comes down to the roofing contractor you hire. Roofing contractors will be able to tell you if a second layer of shingles is even an option for you after a roofing inspection takes place.
Important things to know about adding a second layer of shingles
If you are approved to add a second layer of shingles to your roof there are a few things to keep in mind.
For instance, when you have two layers of shingles on your roof you are no longer able to have your roof sheathing inspected. The roof sheathing is the base of your asphalt roof. There is always a risk of your roof sheathing breaking during the installation of your second shingle layer. If that happens the roofing contractor has to remove the existing shingles to fix the sheathing and then install both sets of shingles again. This extra step extends the process and also can increase the price. Having a second layer of asphalt shingles installed means that there will not be a chance to inspect the sheathing underneath. In other words, there is no way to know if there is existing damage until it is too late. This is one of the risks you take when choosing to install a second layer of shingles as opposed to a new roof.
Warranties are another issue faced with installing a second layer of asphalt shingles. When shingles are installed originally they come with a warranty from the manufacturer. Having an additional shingle layer added on means you will not have an enhanced warranty.
Your roof’s existing flashing
The flashing of your roof also is a deciding factor on if the second layer of shingles is possible. Flashing is the metal that is placed wherever shingles push up against something such as a chimney or wall. When a new roof is installed there is new flashing to go with it. When the second layer of shingles is added, the old flashing has to be used. If the flashing is not capable of handling a second layer of shingles then that option is off the table. During your initial inspection, your contractor will be able to check the status of your current flashing.
Decreasing the lifespan of your roof
Oftentimes adding a second layer of asphalt shingles to your roof will actually decrease its lifespan. Realistically, there are not supposed to be two layers of shingles on a roof. Shingles are not designed with the intent of holding an additional shingle layer on top of them. Having a second shingle layer installed results in the original shingle layer aging faster over time.
If the aesthetic of your home and roof is of importance to you, then a second shingle layer may not be the best choice. If there are any existing imperfections on your current roof they will transfer over to the new layer of shingles added. Your roof will never look as good as it would have if you had just replaced it together. This is just another thing to keep in mind before making a decision.
Knowing the risks
There are definite risks to having a second layer of shingles installed on your existing roof. It is important to take all of this information into consideration before deciding what route you want to take with your roof. Remember, your roof might not even be able to handle a second layer of shingles. That is why it’s important to have a roofer out to perform an inspection before making a decision. It is also important to keep in mind that while having two shingle layers on your roof may seem like a good idea at the moment when it comes time to replace them it will be a hassle. Since three shingle layers are not permitted in most states, you will need to have two shingle layers removed instead of one. This means that you will have to spend more money and it will also take more time for your roof replacement to be finished. There do tend to be more cons than pros to having a second layer of shingles installed. You have to ask yourself if saving a bit of time and money is worth the risks and potentially shortened lifespan of your roof.
We are here to help
While we at Liberty Roofworks would never agree to install a third layer of shingles to a roof, we do install a second layer when requested and possible. Ideally, we strongly recommended installing a new roof instead of adding another shingle layer. We do however know that things happen and sometimes a second shingle layer is the best option for you at the moment. If you are in need of a roof replacement and want to know your options, we are here to help. We will send one of our licensed and experienced roofing professionals to your home to perform an inspection and let you know if a second shingle layer is an option for you. If you are interested in scheduling an inspection or have any questions please contact us.
Here are some frequently asked questions about adding an additional layer of shingles to an asphalt roof. If you find your question was not answered here please contact us and we are happy to answer any questions you may have.
Q: Can you add a second layer of shingles over architectural shingles?
A: Yes, this is possible. However, the aesthetics will not be the same and can at times be more obvious than two layers of the same shingles.
Q: Can you add 3-tab shingles over architectural shingles?
A: No, it is not possible to install 3-tab shingles over architectural shingles.
Q: How many shingle layers are allowed on a roof?
A: Most states allow there to be a maximum of two layers of shingles.
Q: Is it better to remove old shingles instead of adding another layer?
A: Yes, it is definitely better to remove all old shingles and install new ones instead of adding an additional layer.
Q: Can you re-roof other types of roofs?
A: No, it is only possible to add another layer of roofing over asphalt shingles.