Impact Window Grades Explained: Compare & Choose Quality

by Impact Windows Center March 19, 2024

Key Takeaways

Design Pressure (DP) ratings and Performance Grade (PG) ratings are critical for assessing impact window strength and quality.
DP ratings measure the window's ability to withstand wind pressure, while PG ratings are a more comprehensive measure of overall performance.
Higher PG-rated windows offer superior protection but come at a higher cost.
Local weather patterns and building codes should influence the grade of window you choose.
Comparing window grades side by side helps in making an informed decision that balances protection and cost.

What You Need to Know About Impact Window Grades

The Role of Impact Window Grades in Home Safety

Let's start with the basics. The grade of an impact window tells you how well it will protect your home from the elements and potential intruders. This isn't just about keeping the rain out; it's about ensuring that when the winds howl and objects fly, your windows remain intact, keeping you and your family safe.

Understanding the Grading Scale: From Basic to High-Impact

The grading scale for impact windows ranges from basic protection to high-impact resistance. Here's what you need to know:

Basic impact windows are like the entry-level guardians of your home. They can take a hit, but they're not the strongest out there.
Mid-level grades offer better resistance and are a good middle ground for many homeowners.
High-impact windows are the elite protectors, designed to withstand even the most severe weather conditions.

Breaking Down Impact Window Ratings

Design Pressure (DP) Ratings: The Foundation of Window Strength

Think of the DP rating as the window's muscle. It tells you how much wind and pressure the window can handle before it gives in. It's a number that comes from testing the window against increasing levels of pressure to find its breaking point.

Here's what you should look for:

A higher DP rating means the window can withstand more pressure from wind and potential debris.
DP ratings are especially important in areas prone to high winds and hurricanes.
Don't just look at the number; understand what it means for your home's location and weather patterns.

For instance, a window with a DP rating of 50 has been rigorously tested to withstand winds of up to 170 mph, while a DP 30 rated window can endure up to 130 mph. This is critical knowledge when you live in a hurricane-prone area.

But it's not just about the wind. These ratings also take into account the window's resistance to water infiltration and air leakage, both of which can cause significant damage during a storm.

Performance Grade (PG): The Ultimate Measure of Quality

While DP ratings are important, PG ratings encompass a broader range of performance factors, including air infiltration, water resistance, and structural integrity under stress. A high PG rating indicates a window that not only resists strong winds but also has superior overall performance in all weather conditions.

Striking the Balance: Protection vs. Cost

It's a balancing act between ensuring your home is protected and managing your budget. Higher-rated windows come with a higher price tag, but they also offer better protection. It's important to consider the potential costs of not having adequate protection, such as property damage or even personal injury during severe weather events.

Cost-Efficiency of Different Impact Window Grades

When assessing cost efficiency, consider not only the upfront cost but also the potential energy savings, insurance discounts, and increased home value that high-grade impact windows can provide. Over time, these benefits can offset the initial investment.

For example, homeowners in Florida can save up to 45% on their homeowner's insurance premiums by installing impact windows that meet certain criteria.

Additionally, impact windows can reduce your energy bills by providing better insulation and reducing the need for heating and cooling.

When to Invest in Higher-Grade Windows

Investing in higher-grade windows is wise if you live in an area with frequent severe weather or if you value the peace of mind that comes with having the highest level of protection for your home. The investment is also justified if you're looking for long-term savings on energy and insurance costs.

Matching Impact Window Grades with Local Weather Patterns

When choosing impact windows, it's not a one-size-fits-all situation. The grades you need depend heavily on your local weather patterns. If hurricanes are a yearly event, you'll want windows with both high DP and PG ratings. But if you're more concerned with occasional strong winds or potential break-ins, a lower grade might suffice. It's like picking out a winter coat; you wouldn't wear a parka in Florida or a windbreaker in Alaska.

Understanding Regional Building Codes and Requirements

Building codes are the rulebook for your home's safety in extreme weather. They vary from place to place, reflecting the local climate's demands. Your windows must meet these codes, or better yet, exceed them. It's crucial to check with your local building department to know what's required. They'll give you the minimum PG and DP ratings for your area. Ignoring these codes isn't just risky—it can be illegal. For more information, you can read about the basics of impact window ratings to understand how these standards apply to your home.

These codes exist for a reason. They're based on historical data, and they're designed to protect your home against the worst weather your region has seen—or could see. So, when you're looking at window grades, make sure they're not just good but good for where you live.

Check local building codes for minimum required impact window ratings.
Consider the frequency and severity of weather events in your area.
Ensure compliance with legal requirements to avoid fines or insurance issues.

Remember, following these codes is not just about compliance; it's about ensuring your home is as prepared as it can be for whatever Mother Nature throws your way.

Making an Informed Decision: Grade Comparisons

Now that we've laid out the importance of understanding impact window grades, let's dive into how you can compare these grades to make the best choice for your home. It's like comparing apples to apples—you need to know what each grade offers to understand its value.

Side-by-Side Grade Analysis: What Do You Really Get?

Let's put two hypothetical windows side by side: one with a DP rating of 30 and a PG rating of 35, and another with a DP rating of 50 and a PG rating of 70. The first window is decent, but the second one is like a fortress. It's built to withstand much more pressure and severe conditions. But here's the catch: the second window also costs significantly more.

So, what do you really get with a higher grade? Better resistance to wind and debris, better insulation, and potentially lower insurance rates. But most importantly, you get peace of mind, knowing your home has the best protection available.

When comparing grades, always look at:

The DP rating: How much wind pressure the window can withstand.
The PG rating: The overall performance including resistance to air and water infiltration, and structural strength.
The cost difference: Is the higher grade worth the extra investment?

In conclusion, choosing the right impact window grade is about finding the sweet spot between necessary protection and your budget. Armed with knowledge about DP and PG ratings, local weather patterns, and building codes, you're now equipped to make an informed decision. Remember, it's not just about surviving the storm—it's about doing so with confidence and without breaking the bank.