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Gabi Ribeiro
Gabi Ribeiro

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How do you Calculate Ice and Water Shield?


Calculating the necessary amount of Ice and Water Shield (IWS) can be complicated, and mistakes can lead to either overpaying or underestimating the amount needed, putting your home at risk of water damage. In this blog, we will discuss the importance of using IWS for your roofing project and how to accurately calculate it.

What is Ice and Water Shield? 

Ice and Water Shield (IWS) is a type of roofing underlayment that helps prevent water and ice damage. It's typically made from a rubberized asphalt material that's designed to adhere to the roof deck and provide an additional layer of protection against water infiltration. IWS is typically installed at the eaves, valleys, and other areas prone to water infiltration, and it's often used in conjunction with other roofing materials such as shingles, metal panels, or tiles.
IWS is an important component of any roofing system because it helps protect your home from water damage. A leaky roof can cause serious problems such as mold growth, structural damage, and even electrical hazards. In addition, water damage can be expensive to repair and may not be covered by the homeowner's insurance if it's deemed to be the result of neglect or improper maintenance. By investing in IWS, you can help ensure that your roof is well-protected against water infiltration and that your home remains safe and dry. Plus, you'll have peace of mind knowing that you won't have to worry about leaks or water damage, which can be a major source of stress. Remember, your roof is an investment in your home, and taking care of it with quality materials like IWS is a smart choice that can pay off in the long run.
Why is IWS so important?
 Ice dams and other winter weather-related issues can cause serious damage to your roof and home. Fortunately, using Ice and Water Shield (IWS) can help prevent these issues from occurring in the first place. Here's how:
Ice dams occur when snow and ice build-up on your roof, then melt and refreeze along the edges, forming a dam. This can cause water to back up under shingles and infiltrate the home, leading to water damage and other issues. By installing IWS along the edges of your roof, you create a watertight seal that prevents water from penetrating the home, even if an ice dam forms.
IWS can also help prevent other winter weather-related issues, such as leaks caused by melting snow and ice. When snow and ice melt on your roof, it can seep under shingles and cause leaks in the attic and home. IWS acts as a barrier, preventing water from infiltrating the house even in these circumstances.
In addition to preventing water infiltration, IWS can also help protect your roof from damage caused by ice and snow. Snow and ice can be heavy, and when they accumulate on your roof, they can cause structural damage or even collapse. By providing an extra layer of protection, IWS can help distribute the weight of snow and ice more evenly, reducing the risk of damage.
Why Calculating it Correctly Matters
As we explained, calculating the necessary amount of IWS accurately is crucial to avoid future water damage and leaks. Underestimating the required amount of IWS can lead to vulnerable areas on the roof that are not adequately protected. These unprotected areas can become entry points for water, leading to leaks and potential water damage in the future. Not only can this cause significant inconvenience and expense for homeowners, but it can also create additional issues such as mold growth and damage to the structural integrity of the home. So, it is essential to use an accurate estimation method to ensure the correct amount of IWS is used to protect the roof and the home.
While underestimating the necessary amount of Ice and Water Shield (IWS) for a roofing project can be problematic, overbuying can also lead to issues, namely, overpaying. If you purchase more IWS than you actually need, you may end up paying significantly more than necessary. This is why it's important to accurately calculate the required amount of IWS using a reliable method such as a calculator, to avoid overbuying and overspending.
Overbuying can also result in unnecessary waste, which can contribute to environmental concerns. By purchasing only the necessary amount of IWS, you can minimize waste and reduce your environmental impact. In addition, by avoiding unnecessary waste, you can potentially save money on disposal fees or recycling costs.
Overall, finding the right balance when it comes to purchasing IWS is important. This way, you can help protect your home from water damage while also reducing waste and saving money.
Common mistakes in Calculating IWS
While calculating the necessary amount of Ice and Water Shield (IWS) for your roofing project can be tricky, there are some common mistakes that you can avoid to ensure that you get it right. One common mistake is not taking into account the pitch of your roof. The steeper the pitch, the more IWS you will need to adequately protect your roof. Another mistake is not accounting for all the penetrations and valleys on your roof. Each of these areas will require additional IWS to ensure that they are properly protected.
Another mistake to avoid is not taking into consideration the size of your roof. It's important to measure your roof accurately to ensure that you purchase the right amount of IWS. Additionally, it's important to account for any waste that may occur during the installation process, as this can impact the amount of IWS that you ultimately need.
What’s the solution?
Calculating the necessary amount of Ice and Water Shield (IWS) for a roofing project can be a challenging task. Underestimating the amount needed can lead to water infiltration and damage, while overestimating can result in unnecessary costs. To help contractors and adjusters make an accurate estimation and save time and money, OneClick has designed an IWS Calculator. Our calculator takes into consideration several crucial inputs, including the pitch and size of the roof, valley length, soffit depth, etc. By utilizing our calculator, contractors and adjusters can more quickly and accurately estimate the amount of IWS required for the project, streamlining the insurance claims process, and providing homeowners with peace of mind knowing their roof is well-protected.
Apart from that, you can get your results in actual square footage or by full and half rolls. This way, not only do you know how much you’ll actually use, but you’ll also know how much you will actually need to buy.
Our calculator is easy to use and takes only a few minutes to provide the necessary information. It eliminates the guesswork from the process and ensures that the correct amount of IWS is used for each project, avoiding costly errors and potential damage to the home.

About OneClick Code

OneClick Code is a trusted data partner, dedicated to streamlining the code-sourcing process for all parties in the roofing industry while also increasing efficiency and transparency for all stakeholders in construction and restoration. They have the only platform to have blazed the trail for data automation of jurisdictional authority for building codes, permit fees, taxes, and manufacturer specifications required for any address nationwide. OneClick Code has been serving customers in the contracting, insurance, and claim adjusting fields by providing instant access to trusted roofing codes, in the click of a button. Offering unique reports that can be easily shared between all stakeholders in the roofing claims industry, OneClick is adding value to all parties and empowering customers to save time and money on every claim. Welcome to restoration intelligence, automated. To learn more, visit our website

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