Types of Windows for Texas Metal Buildings
Discussions of the differences between single-pane and double-pane windows are not common in the metal building industry. However, choosing the right type of window for your Texas metal building is essential to making it last.
At WolfSteel Buildings, we’ve learned that steel building windows are an important component of your metal building especially when it comes to water management.
In today’s blog, we’ll break down the key differences between single pane and double pane windows, their installation process in metal buildings, and the reason behind our decision to ONLY offer double pane windows.
Why Windows are Essential for Your Texas Metal Building?
Windows are important for your Texas metal building not only for natural light, ventilation but for managing water. In construction, water is the biggest enemy – it quickly finds the weak spots. Thus, choosing the right windows can help protect your building from costly water damage.
Single Pane vs. Double Pane Windows
Now that we’ve covered why windows matter, let’s take a look at the difference between single pane and double pane windows.
What are Single Pane Windows?
Most commonly offered options for tubular metal buildings because the industry began with carports, sheds, and barns. These are structures that don’t require insulation.
Insulation Benefits:
Composed of one sheet of glass with no insulation. It does the job on non-insulated spaces but has certain limitations such as:
- Maintaining the inside temperature can be difficult due to energy leakage when the glass is broken, as there is only 1 layer of glass.Â
- Radiant heat penetrates quickly when the Texas sun hits your building; you can feel it radiating even from a few feet away.
- Unable to meet the energy codes, hence, not suitable for residential or commercial use.
Nail Fin vs Flush Fin Window Design:
Single pane windows have flange or “fin” attached to the exterior edge of the jamb. This design is referred to as flush fin which is commonly used for wood siding or stucco installations where the sidings overlap the flange to prevent water from seeping through. This works effectively particularly when used with solid sheathing such as OSB, plywood or a ZIP system with house wrap placed behind it.
On the other hand, metal buildings are different. PBR and AG panels have a corrugated steel design extending from ¾” to 1-¼” away from the frame. These panels are typically attached directly to the tube frame without additional insulation or protective covering.
We need to use a J-trim to flash the windows to resolve this issue.
- 1” for AG panels
- 1-½” for PBR panels
Flush Fin Design for Single Pane Windows
However, the problem arises when you attach a flush-fin window with a J-trim, causing it to stick away from the frame. This means that we need to use caulk to fill the space between the J-trim and the window fin, but this is just a temporary fix. The extreme heat in Texas can cause the metal to expand and contract, making the caulk ineffective over time. Eventually, the separation happens, and water can now freely flow.
The large J-trim also creates a deeper sill, a catch point where water can accumulate and gradually seep back into the structure.
Weep Drainage System:
Single pane windows do not include a weep drainage system. The frame and sash are pretty basic and are often sealed with caulk in the corners. While this may be enough to hold them up for a few years, the caulking can break down over time especially in Texas weather. Once the seal fails, the water has nowhere to go but inside.
How much does a single pane window cost?
Single pane windows typically range from $200 to $300, including the window itself, the installation, the trim, and the frame out. This is a cost-effective option, but you get what you pay for.
What are Double Pane Windows?
Double-pane windows are insulated windows that are highly recommended for workshops, garages, or any metal building that will be insulated. They are perfect for residential or commercial use.
Insulation Benefits:
Unlike single-pane windows, double-pane windows are made up of two layers of glass. They have an interior and an exterior pane with argon, krypton, or sometimes air in between. The trapped gas in between the gaps creates insulation. It slows down heat transfer and helps regulate the temperature inside the metal building.
Nail Fin vs Flush Fin Window Design:
Depending on the type of frame and exterior finish of your metal building, you can choose between the nail fin and the flush fin. Nail fin is the right choice for metal building. It sticks out near the center of the window frame, which allows the J trim to wrap around it cleanly—about a ¼” to ½” out.
Nail Fin Design for Double Pane Windows
Due to the tighter fit, we only need minimal caulk, which means less maintenance. With the right slope and flashing, gravity does the work and directs the water away from the windows instead of sitting on them.
Weep Drainage System:
Double pane windows are typically equipped with the weep drainage system that allows any trapped water in the window sash or sill a clear path to drain out. This is similar to the weep holes in the brick system that are designed to let trapped moisture escape before it causes problems.
Weeping Drainage System in Double Pane Window
This feature is essential, especially here in Texas, where heavy rain and high winds slam water right up against the face of the window. The weep drainage system helps prevent water from sitting on the sash or sill.
How much does a double pane window cost?
The price is between $350 and $600, which includes the window itself, the installation, the trim, and the full frame out installed by either red iron builders or tubular metal building companies. The upfront cost is higher than single-pane, but it pays off in comfort, efficiency, and long-term performance.
Side-by-Side Comparison Between Single Pane and Double Pane Windows
Here’s a side by side comparison between single pane and double pane windows.
Feature | Single Pane Window | Double Pane Window |
|---|---|---|
Insulation | None | Yes – Argon/Krypton Gas or Air Layer |
Energy Efficiency
| Fails code in most states | Meets energy codes
|
Water Management | No weep drainage system
| Built-in weep drainage system |
Installation on Metal Buildings | Heavily relies on caulking for sealing
| Tighter fit with Nail Fin + J-Trim
|
Maintenance | High (Caulk touch-ups) | Low ( if flashed properly)
|
Price Range (Installed) | $200 – $300
Installation Included | $350 – $600
Installation Included |
Long-Term Viability
| Low | High |
Why WolfSteel Buildings ONLY Offers Double Pane Window?
At WolfSteel Buildings, we prioritize long-term quality and performance. After years of experience and seeing the challenges single pane windows cause especially in harsh Texas weather we’ve made the decision to no longer offer them on our projects.
Here are the reasons:
- Texas weather can be tough, especially during the months of April to May, when storms occur. Heavy rain, strong winds, and sideways water are common during this season. That’s why we only offer double-pane windows that have a weep system.
- Most of our buildings are used as man caves, workshops, or residential/commercial spaces where good flashing and water management around metal siding are critical to avoid leaks. We know that flashing right away around the metal siding is challenging but we’d rather instead of getting a phone call down the line about water leaking in.
- About 95% of our buildings get insulated eventually, making double pane windows much more valuable for energy efficiency and comfort.Â
- We’ve had clients call us asking to swap out their windows because they were losing energy and couldn’t keep their workshop comfortable. In other cases, water intrusion damaged the interior framing.
- Also, once spray foam is involved, this can get more complicated. Spray foam bonds really hard directly to the metal panels and trims. If you need to replace your single-pane window with a double-pane window, this will involve a special cutting, which can cost additional labor. To avoid the additional cost, you might as well use the double-pane from the start.
- We focus more on leak-proof construction and double pane windows with a weep drainage system fit this standard. They give a better seal, better drainage and peace of mind.
What does WolfSteel think?
Choosing double pane over single pane windows may cost upfront, but their energy savings, improved insulation, and better leak prevention make them a smarter investment over time. With double pane windows, you’ll have fewer repairs, lower energy bills, and greater comfort in your building for years to come.
Tip: If you are working with a company that only offers single pane windows, most tubular companies will let you bring your window. Make sure to bring a double pane to avoid the hassle of switching it in the future and to have it present at the time of install.
At WolfSteel, we designed our custom trim system with a kick-out, redirecting water away from the window edges where 99% of leaks typically occur. This system significantly reduces the reliance on silicone for waterproofing, ensuring a more durable and long-lasting seal.
If you’re still not sure whether to use double pane or single pane, consult with us!
More questions for double pane windows?
đź“© Email us at quotes@wolfsteelbuildings.com or give us a call at 844-941-0999. Our team is ready to answer your questions.