Can You Install New Shingles Over An Old Ice And Water Shield?

Posted on October 25, 2023

Estimated Reading Time : 3 Min.

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Can You Install New Shingles Over An Old Ice And Water Shield?

When an old ice and water shield is replaced on a roof, the process can be messy, since all the shingles have to be torn off to reach it. Unless the shield or roof deck is severely damaged,  many homeowners wonder if they can simply install new shingles over an old ice and water shield, instead of completely replacing it.  

In this blog post, we’ll briefly explore whether or not installing shingles over an old ice and water shield is a good choice. Keep reading it till the end to get an answer from experienced roofers. 

What Exactly Is An Ice And Water Shield? 

Will Shingles Stick To Old Ice &Amp; Water Shield? - New Jersey Roofing Contractor

An ice and water shield, also known as an ice and water barrier, or underlayment, is a roofing material that protects the roof deck against water infiltration. Ice and water shields are generally installed in areas on the roof where the chances of ice dams and water infiltration are more likely to occur. 

They are self-adhering rubberized asphalt membranes with a sticky backing that forms a strong bond with the roof deck, preventing ice and water from flowing into the interior of the roof. Here are some key characteristics and purposes of water and ice shields:

Also, Read:  Do You Put Underlayment Over An Ice And Water Shield? 

The Purpose of Installing An Ice And Water Shield

1. Waterproofing

An ice and water shield is very waterproof and prevents water from penetrating the roof deck, which is essential for preventing leaks.

2. Ease of Application

The backing of the membrane is covered with a release paper that is removed during installation. Once the release paper is removed, the material sticks to the roof deck, creating a watertight seal. Ice and water shields have excellent adhesive properties, ensuring a solid bond with the roof deck, even in cold temperatures.

3. Ice Dam Prevention

In regions with cold winters, ice dams can form on the eaves of roofs, causing water to back up under the shingles. Water and ice shields help prevent this by creating a barrier that stops melting snow and ice from penetrating the interior of your roof.

4. Additional Layer of Protection

The shields are typically installed in areas where leaks are more likely to occur, such as eaves, valleys, and around roof penetrations like chimneys and vent pipes. It is installed beneath the roofing material (shingles or other roofing materials) and acts as a secondary layer of protection against water intrusion. 

Now, let’s get back to the core question of this blog post: Can you install new shingles over an old ice and water shield?

If Your Old Ice And Water Shield Has No Damage, Can You Install New Shingles On Top of It? 

If the ice and water shield is free of damage, you should have no problem installing new shingles on top of it. However, the proper installation techniques are crucial here, including proper overlap and nailing, in order for the shingles to form a weather-resistant barrier over the top of the shield. 

Keep in mind that if the ice and water shield was significantly exposed to the elements for longer than 90 days, or if it’s reaching the end of its lifespan, it’s highly recommended to replace it before installing the new shingles on top of it. 

Are You Looking For A Roof Replacement In Montclair, New Jersey? 

If you are looking to get a roof replacement in Montclair, New Jersey, consider Northkit Roofing, a local and skilled roofing company. The experienced team of roofers at our company are skilled and proficient at handling any type of roofing project, including roof installation, roof replacement, and repair. Just give us a call today at (973)-396-7416 to learn more and speak with one of our experts.

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