It’s never a good scene when asphalt shingles reach the end of their lifespan. Signs include constant leaks, shingle loss, and mold that may force a roof replacement. However, replacing an asphalt shingle roof without a good budget can be overwhelming.
You need to reap off the existing roof to install a new one. If your roof sheathing cannot handle the new roof, you will need to replace everything.
However, sometimes you want to apply a new roof shingle over your first layer. This will be applicable if your sheathing and roof structure is still intact. You can see recommendations from reputable roofing contractors.
But the question is, how many layers of shingles are allowed in PA? We will be answering this question here.
How Far to Take Your Roof Overlay
A full roof replacement can be expensive. There are expenses for buying new shingles and disposing of the old roof. According to the local building codes, you can have up to two layers of shingles on your existing roofs. Some people may want three layers, but that may only get you in trouble.
A second layer may be added, to your existing roofs, unless:
- You already have a double layer of shingles or two or more roof covering applications.
- The roofs feature slate, clay, or asbestos
- The current material is water-soaked, or the roof structure is not strong enough to hold the second layer of shingles.
The roofing industry in every region has clear guidelines on how to deal with such issues. For example, the roof deck must be properly inspected to determine whether it’s eligible to hold more roofing components.
Experts will need to also check the roof flashing, the old shingles, and other roofing components to ensure they are all in good order. Even if your existing layer is in great condition, and the roof is eligible for re-roofing, industry experts will tell you multiple layers is not a professional approach.
Are There Benefits to More Than One Layer of Shingles?
We still encourage a complete replacement, especially for architectural shingles, which are more vulnerable to weather extremes. Nevertheless, depending on your roof’s pitch, you can have new shingles installed to make a double layer. Very rare occasions allow for three layers due to the risks they pose.
With proper installation, you should have more layers on your roofing system without many issues. Here are some of the benefits you can get:
It takes a lot of money to tear off a roof. There are significant costs involved when stripping the old roof and installing a completely new layer.
Aside from replacement costs, there are also costs to dispose of the old shingles and other materials. You can save on all of these costs by simply adding another layer.
There is actually a lot of time involved in the entire replacement process. From the time you start stripping off the old roof to the time a new layer is instilled, you could have done so many things. Hence, you can take less time.
Also, the underlying wood will be exposed for too long as you lay the new shingles. This can be a problem when there is rain, say in the afternoon. It will soak the wood.
Possibly reduce the likelihood of ice dams
A second layer creates something like an ice shield over the shingles. Sometimes this can be a real problem during winter, affecting the integrity of your roofing system.
Should You Have More Layers of Your Roof Then?
In summary, multiple layers of shingles can reduce the labor costs involved in replacing the whole roof. It also makes the work easier. Buy should you do it?
Experts do not recommend it. A single layer of new shingles improves your home’s curb appeal while saving you on future costs. Here are the reasons why a full replacement is better than multiple layers of shingles.
Roofs are more than just layers of the material
For many homeowners, roofs are systems and not simply layers of shingles. The roofing system protects the home interior from elements like high winds and rain and keeps the energy in. It’s a system of barriers featuring flashing and counter flashing, waterproofing, a wooden roof deck, shingles, and more.
Adding on a second layer blocks you from checking the other elements. It becomes hard to inspect the roofs. Insurance companies will pay for a complete tear-off of the roof.
Re-covering affects the warranty
Even if you follow all the building codes, adding shingles to the first layer makes warranties void. Both the first layer and the second one is affected. If a manufacturer offers a 35-year warranty, the new layer will not have a warranty, and neither will the old one.
This can cost you more in case the roof has a serious issue. All roof components cannot be installed without removing the old ones.
Issues with insurance companies
You can claim a homeowners insurance policy, and the issuer will cover a complete replacement. This is because an inspection is carried out to reveal any rotten, deteriorated, or delaminated sheathing to understand what must be done. Some companies will not pay the insurance.
The extra weight
Shingles don’t normally weigh much per square foot. However, that extra 2 to 3 pounds can add up weight quite fast. Besides, second-layer shingles are often designed to weigh more to disguise missing shingles of depressions. Additionally, the fasteners like nails or staples must be longer and heavier.
Your building may need more structural strength to handle such factors. Or the roof could already be weak and damaged. The weight will initiate movement and settling of the house, which causes cracks in the foundation.
You may avoid the roof replacement costs now, but understand that you will be dealing with more material when you want to replace the roof in the future. You now have two roofs, which could make disposing of them more expensive. Also, this can prevent flashing open valleys, chimneys, and similar areas from effectively.
Are You a Good Candidate for Roof-Overlaying
Certain roofing situations may require a complete tear-off, where repairs are no longer applicable. Homeowners in PA can have up to two layers of singles. Here are some conditions that are right for re-covering:
- The roof itself is not rotten or damaged. Your roofer may need to thoroughly inspect the roof before determining its eligibility for an overlay. You can have another layer if the roof is still in good condition.
- The damaged shingles are only on one side. An overlay can be a good idea if these shingles are one section of the roof, but the rest is good.
- The majority of the roof does not require shingle replacement. If more than ¾ of your roof is still in great condition, you can avoid the cost of roof replacement.
- Your roof only has one layer. Unless your roof already has multiple layers, your contractor may recommend another layer.
We recommend that you replace the existing material. But if you choose to use an overlay, then you must consider several factors. These include the warranty terms, extra weight on the roof, future repairs/replacement, and insurance coverage. Also, if your current roof is severally damaged, a full replacement is your best option. Let In The Light Contracting help you get a high-quality roof.