Replacing your old roof with a new one is a big investment for your home, so you want to make sure it’s done right. There are many reasons to replace your roof — age, leaking, damage, and more. So, when time comes for a new roof, there are two main methods contractors and installers typically follow: roof tear off or roof overlay. Now let’s take an in-depth look at both methods, as well as providing the pros and cons for each.
What is Roof Overlay Vs. Tear Off?
When you’re getting a new roof installed on your home, there are two main ways a contractor can install it:
Roof tear off is when the entire old roof is removed completely, and the new roof is installed in its place with all new materials.
Roof overlay is when your old, existing roof remains in place and the new roofing system is installed directly over top of it.
So, which method should you consider?
Pros & Cons of Roof Tear Off
Completely tearing off your old roofing system to install a new one can have quite a few different advantages and disadvantages.
Pros
Catch Underlying Issues — One of the biggest benefits of a complete roof tear off is that your contactor/installer will be able to thoroughly inspect and repair any structural issues that may have otherwise gone unnoticed and caused even bigger problems down the road. They can catch any leaks, signs of mold or rot, and other damages that may have remained in place if the overlay method was used.
All New Materials — With roof tear off, you’re also able to upgrade all your roofing system materials to new ones, including the decking, underlayment, and more. This is especially beneficial when you may not have even known these components had issues like we mentioned above.
Increased Lifespan — A complete tear off can allow you to be confident that your new roofing system will last up to and even longer than its expected lifespan because of all the brand-new materials.
Lower Maintenance — Since your entire roofing system is being replaced with brand new materials, the need for maintenance is significantly lower. Metal roofing is already an extremely low maintenance material, and when you completely replace all the other components of the system, you can enjoy an even more low maintenance roof. Especially because the chances of issues occurring down the road are lowered, too.
Increased Home Value — The tear off method increases your home’s value. A new roof alone significantly increases a home’s resale value, and when you completely replace all aspects of the roof, it even further increases.
Cons
More Costly — When compared to the overlay method, tearing off is more costly because it requires more time, labor, and materials, as well as disposing of the old roofing material. However, many homeowners find the investment to be well worth it considering that underlying issues can be addressed and issues down the road can be avoided, especially those that may require the new roof to be removed to fix.
More Time & Materials — Roof tear off will take more time than overlay, and also requires more labor and materials (thus the increased cost).
Pros & Cons of Roof Overlay
There are also a few different benefits and drawbacks to consider for the roof overlay installation method.
Pros
Quicker Project Completion — Since the new material is just being installed directly on top of the old material, roof overlay is significantly quicker than tear off.
Cost Effective — Overlay costs a lot less for installation because it doesn’t require as much time, labor, or materials. Plus, you don’t have to pay for the disposal of your old roofing materials.
Cons
Increased Chance of Trapped Moisture — When you lay new materials directly down on top of old materials, the chances of water vapor and other forms of moisture getting trapped between the two sets of materials increases. This can lead to an increased chance of new mold, rot, and other water damage occurring.
Structural Stress & Added Weight — When you choose the overlay method, you are adding another roof to your home, which increases the weight on top of your structure significantly. The added weight could possibly put the structural integrity of your home at risk, especially as time goes on.
Uneven Application — When you lay a new roof over the old one, there is an increased possibility of an uneven application. The old roof may have undergone wear and tear over the years that caused it to become uneven. This can affect both performance and aesthetics.
Possibly Void Warranties — If you do decide to go with the overlay method, it’s extremely important to talk to your roofing provider about the warranty and any issues related to it with this type of installation. In many cases, ordinary warranties will be voided if the overlay method is used because the abrasions from the “rocks” on shingles can cause backside wear as the metal expands and contracts from both hot and cold temperatures. Again, it’s very important to check on your warranties before choosing a method.
