The first time I had to source storefront windows for a hotel project, I felt overwhelmed. Every catalog promised strength, beauty, and reliability, but most sounded the same. The more I compared, the less certain I became.
I wished someone had shown me which companies were actually worth trusting.
Like you, I wanted windows that looked good and held up over time. Through trial and error, I learned that the manufacturer makes all the difference. That’s why I decided to put together this review.
In this article, you’ll see eight storefront window manufacturers that stand out. Each one has been reviewed based on their reliability, durability, and design range.
By the end, you’ll have a clear idea of which supplier can give you windows that last and look right for your property.
So let’s get started!
Quick Comparison Chart
Before diving into the details, here’s a quick side-by-side look at the eight storefront window manufacturers. Think of this as a snapshot to help you see the big picture before we go deeper.
| Manufacturer | Location | Products (Key) | Certifications & Reputation | Limitation / Not Ideal For | Best For |
| YKK AP | Georgia, USA | Storefront systems, entrances, architectural windows, sun control | Known for strict testing; strong presence in LEED-certified projects | Less flexible for highly customized projects | Large commercial and institutional builds |
| Tubelite | Michigan, USA | Storefronts, curtain walls, entrances, sunshades | ISO-certified; respected for consistent aluminum systems | Narrower product range compared to bigger global brands | Mid-sized commercial projects needing durability |
| Vallisco | Shanghai, China | System windows, composite, insulated glass, slim aluminum | Factory-direct, international presence; focus on energy-saving solutions | Single-door or window orders not accepted | Villas, hotels, inns, B&Bs, and greenhouses |
| AGA (Architectural Glass & Aluminum) | California, USA | Storefronts, curtain walls, punched openings, window walls | Employee-owned; reputation for handling complex glazing projects | Longer lead times due to custom-only approach | Large, complex architectural glass projects |
| Internorm | Austria | uPVC, uPVC-aluminum, timber-aluminum windows, sliding doors | Passive House certified; nearly 100 years of trust | Limited distribution and support outside Europe | European villas, hotels, and residential builds |
| Oknoplast | Poland | PVC windows, aluminum windows, patio doors, roller shutters | ISO 14001 sustainability certified; 60+ patented solutions | Distributor network can create inconsistent buying experience | Stylish, affordable, energy-efficient projects |
| J. Sussman, Inc. | New York, USA | Aluminum windows, thermal systems, skylights, bent glass | Family-owned since 1906; trusted in historic projects | Not ideal for standardized, high-volume storefront systems | Custom, historic, or specialty glass projects |
| VEKA AG | Germany | uPVC window profiles, doors, shutters, sliding systems | ISO 9001, ISO 14001 certified; global leader in uPVC extrusion | Does not produce finished windows depends on local fabricators | Large-scale, sustainable uPVC system supply |
Now that you’ve got the quick snapshot, let’s dive deeper into each manufacturer.
1. YKK AP
- Location: Austell, Georgia, USA
- Website: ykkap.com
YKK AP was established in 1991 as part of the global YKK Group, a company best known for its zippers. Over the years, its U.S. division has grown into a major player in the fenestration industry, employing more than 1,000 people and serving clients nationwide.
What stood out to me early on was how their storefront systems handled wide spans without compromise. I’ve seen engineers turn to them when other options fell short, and that experience gave me confidence in their capabilities.
Product Range
- Storefront Systems: These frames are engineered for heavy-duty performance while still allowing flexible design choices. They are commonly used in commercial spaces that demand both durability and modern aesthetics.
- Entrance Systems: Built from aluminum, these doors are designed for high-traffic conditions. They balance strength with smooth operation, making them suitable for retail and public buildings.
- Architectural Windows: YKK AP offers windows that combine energy efficiency with design appeal. They support natural light while maintaining insulation and comfort indoors.
- Sun Control Solutions: These systems integrate shading elements to reduce solar heat gain. By managing sunlight, they help lower cooling costs and improve occupant comfort.
Research & Development (R&D)
- Impact & Thermal Testing: YKK AP operates in-house labs that test for impact resistance and thermal performance. This helps them meet demanding building codes and energy standards.
- Proprietary MegaTherm® Technology: This technology improves insulation in aluminum frames. It reduces heat transfer and makes storefront systems more energy efficient.
- Sustainability Focus: Their systems are adapted to support green building certifications like LEED. This allows architects to meet environmental goals without sacrificing design.
- Moisture & Span Solutions: New products are developed to handle water resistance and long-span performance. These innovations keep projects on schedule by reducing onsite issues.
Customer Support & After-Sales Service
YKK AP provides technical representatives, detailed documentation, and training for installers. In my experience, their team responds quickly to engineering questions, offering practical solutions that help projects move forward. While their size sometimes makes personalized service less immediate, the depth of knowledge and resources available more than makes up for it.
Final Thoughts
YKK AP is a dependable choice for large commercial or institutional projects where strength, energy efficiency, and tested systems are critical. However, if you’re seeking highly customized storefronts, you may find their options more standardized.
2. Milgard Windows & Doors
- Location: Tacoma, Washington, USA
- Website: milgard.com
Founded in 1958, Milgard began as a small glass company serving the Pacific Northwest. Over six decades, it has grown into one of the largest window and door manufacturers in the western United States.
Today, Milgard operates multiple factories and employs thousands of people. Its scale allows the company to serve both homeowners and builders while maintaining consistent service standards.
Product Range
- Vinyl Windows: These windows are affordable and energy-efficient. They require very little upkeep, making them practical for most residential projects.
- Fiberglass Windows: Fiberglass frames resist warping and swelling. They hold their shape well in different climates, offering long-term durability.
- Aluminum Windows: Aluminum offers slim frames for a modern look. They are popular in projects where style and light are priorities.
- Doors: Milgard produces sliding patios and French doors. These are built to match their window systems and provide smooth indoor-outdoor transitions.
Quality Control & Assurance
Milgard maintains control by producing its own vinyl and fiberglass materials in-house. Products go through strict testing for strength, energy efficiency, and long-term durability. Many lines meet Energy Star standards, confirming compliance with U.S. government guidelines. By sourcing and testing internally, Milgard lowers defect rates and delivers reliable, consistent quality across product categories.
Customer Experience & Support
- Warranty Coverage: Milgard provides lifetime limited warranties. This gives you confidence that long-term support is available for many product lines.
- Service Channels: You can reach them through phone, email, or online chat. This flexibility makes it easier to get help in the way that works for you.
- Dealer Network: Authorized dealers handle installation and service. This local presence adds convenience for projects across the western U.S.
- Response Time: Warranty claims are generally resolved quickly. Many customers value the responsiveness of Milgard’s service team.
Final Thoughts
Milgard is best for homeowners and project teams seeking reliable products with strong after-sales support. However, its presence is strongest in the western U.S., which may limit access nationwide.
3. Vallisco
- Location: Building 1, No. 1926, Cao An Highway, Jiading District, Shanghai, China 201824
- Website: vallisco.com
Vallisco became an independent brand in 2024, building on more than 20 years of experience through its parent company, Qeeka Home. Its operations grew stronger in 2019 when a dedicated doors and windows factory was acquired, giving full control of production.
Today, Vallisco supplies projects across Southeast Asia and Europe, working with villas, hotels, inns, B&Bs, and greenhouses.
What stands out is the factory-direct model. Buyers deal directly with the team that manufactures the products, which creates more transparency and confidence throughout the process.
Product Range
- System Windows: Built for insulation and stability, making them reliable for large commercial or residential projects. They are designed to handle heavy use without losing performance.
- Composite Windows: Made by combining materials to balance durability with visual appeal. They work well for properties that need strength and style in one product.
- Insulated Glass Windows: Feature multiple layers of glass that reduce outside noise and help control temperature indoors. They are especially useful in busy city environments.
- Slim-Frame Aluminum Windows: Use thin profiles to maximize natural light and create modern aesthetics. These frames give a sleek look while maintaining strength.
Research & Development (R&D)
- In-House Expertise: Designs are created within the company, giving full control over quality and performance. This approach helps maintain consistency from concept to finished product.
- Adaptability: Products are tested to perform in varied climates, from humid Southeast Asia to colder European regions. This makes them suitable for different environments.
- Energy Efficiency: Thermal break systems and insulated glass are developed to lower heating and cooling costs. These features help properties stay comfortable with less energy use.
- Design Updates: New models are released to match changing architectural needs. This keeps the product line aligned with modern building trends.
Customer Support & After-Sales Service
Vallisco provides project consultations, phone and email communication, and technical support for builders and owners. Their team is known for quick responses and flexibility in handling project-specific needs, which can make the process smoother.
Final Thoughts
Vallisco is a good choice for projects where modern design, durability, and direct communication with the manufacturer are important. However, the company does not serve customers looking to buy only one door or window, and is better suited for multi-unit orders such as villa renovations or hotel builds.
4. Architectural Glass & Aluminum (AGA)
- Location: Livermore, California, USA
- Website: aga-ca.com
Architectural Glass & Aluminum (AGA) was founded in 1970 and has become one of California’s leading specialty glazing contractors. The company is employee-owned, which means every project is delivered by a team with a direct stake in its success. AGA focuses on designing, fabricating, and installing custom glass and aluminum systems for commercial buildings.
Their strength lies in taking projects from concept through installation without splitting responsibilities across different firms. For owners and contractors, this approach reduces confusion and provides one clear line of accountability throughout the building.
Product Range
- Custom Storefront Systems: Built for demanding use and designed to adapt to a variety of architectural styles. They combine strength with visual appeal.
- Curtain Wall Systems: Expansive glass walls that create open interiors with plenty of light. These systems are engineered to withstand wind and weather.
- Punched Openings: Framed sections of glass fitted into building facades. They provide efficiency and a clean, straightforward look.
- Window Wall Systems: Pre-assembled panels that combine framing and glass. They speed up construction while maintaining quality.
Research & Development (R&D)
- Engineering Expertise: AGA relies on in-house engineering to shape project-specific solutions. This gives them flexibility when dealing with complex designs.
- Performance Testing: Systems are tested for water, air, and thermal resistance. This reduces the chance of problems after installation.
- Material Innovation: Glass is combined with stone, metal, or shading devices. This widens design choices for architects.
- Energy Code Alignment: Products are continually updated to meet stricter energy standards. That helps projects stay compliant without last-minute changes.
Customer Support & After-Sales Service
Clients benefit from working with one team that manages design, fabrication, and installation. This makes communication easier and reduces delays caused by multiple contractors. The downside is that custom work often requires longer lead times compared to standardized systems.
Final Thoughts
AGA is well-suited for large commercial or institutional projects where design complexity and performance are equally important. However, for buyers seeking simple, off-the-shelf storefront systems, their approach may feel more involved than necessary.
5. Internorm
- Location: Traun, Austria
- Website: internorm.com
Internorm was founded in 1931 when Eduard Klinger Sr. set up a metal‑work and construction workshop in Linz. It later introduced uPVC (rigid plastic) window production in 1966, becoming Austria’s first specialist in that area.
Since then, it has grown into Europe’s leading family-run window and door manufacturer, with around 1,800 employees, over 1,300 distribution partners, and full production located in Austria Traun, Sarleinsbach, and Lannach. The company remains wholly family-owned, now in its third generation of leadership.
Product Range
- uPVC Windows: Durable and low-maintenance, these windows are common in homes across Europe. You’ll notice they also perform well in energy savings, which makes them a practical option for long-term use.
- uPVC-Aluminum Windows: Blend the insulation of uPVC with the durability of aluminum. I’ve seen these work best in modern homes where style and performance are equally important.
- Timber-Aluminum Windows: Natural wood inside and aluminum outside. They’re popular with property owners who want warmth indoors without giving up weather resistance outdoors.
- Sliding Doors and Entrance Doors: Extend Internorm’s window systems with consistent performance. They create seamless transitions between indoor and outdoor spaces.
Research & Development (R&D)
- I-tec Innovations: Proprietary features like I-tec Locking and I-tec Shading make daily use easier. These little touches matter if you value convenience and security.
- In-House Development: Designs are tested internally, which keeps performance reliable across projects. From my perspective, this consistency is what reassures builders.
- Sustainability Focus: Systems are engineered for low energy consumption. That’s especially helpful if you’re aiming for compliance with European green building codes.
- Market Adaptation: Products are updated to reflect modern architectural needs. This means you don’t have to compromise between design trends and performance.
Customer Support & After-Sales Service
Internorm relies on its partner network with showrooms and local representatives. If you’ve ever had to choose windows from a catalog alone, you’ll appreciate being able to see and test products in person. The drawback is that outside Europe, access to this kind of support is limited, which can complicate international projects.
Final Thoughts
Internorm is a strong choice for European projects that require a mix of tradition, innovation, and tested reliability. However, for projects outside Europe, limited service networks may make them harder to work with.
6. Oknoplast
- Location: Ochmanów, near Kraków, Poland
- Website: oknoplast.com
Oknoplast was founded in 1994 as a family-owned PVC windows and doors manufacturer in Kraków. In just a few years, it expanded production into aluminum joinery and moved operations to Ochmanów, where its main plant remains today. The company has grown into one of Europe’s largest suppliers of PVC and aluminum systems.
Now employing more than 3,000 people across six factories in Poland, Spain, and Austria, Oknoplast produces over 2 million window units each year. Its reach extends to 21 countries, supported by more than 3,500 showrooms across Europe, making it one of the most widely available brands in the market.
Product Range
- PVC (uPVC) Windows: Durable and low-maintenance, widely chosen for everyday residential projects. Many owners appreciate that they hold up well without frequent repairs.
- Aluminum Windows: Provide stronger frames for larger glass panes. One detail that caught my attention was how these systems give modern facades a clean, open look with wide, uninterrupted views.
- Patio & Sliding Doors: Easy to operate and thermally efficient. They’re especially useful in properties that value seamless indoor–outdoor transitions.
- Roller Shutters: Improve shading and security while blending into the design. Customers often point out how these quiet additions make homes feel more comfortable.
Research & Development (R&D)
- Innovative Leadership: Oknoplast holds more than 60 patents, many of which have shaped European window standards.
- Advanced Production: Automated factories keep quality consistent while reducing human error.
- Sustainability Focus: Certified to ISO 14001, Oknoplast recycles materials and integrates solar energy into its plants【gw-news.eu】.
- Market Adaptation: Regional variations are produced, from Italian-style sliding systems to hurricane-resistant windows for Florida.
Customer Support & After-Sales Service
With thousands of showrooms across Europe, you can test finishes, frames, and operation modes before ordering. That hands-on access feels reassuring when choosing such a visible part of a property. Outside Europe, though, direct service may be less accessible, and buyers often depend on distributors.
Final Thoughts
Oknoplast is a strong option for projects in Europe where style and energy performance both matter. However, because they work through such a large distributor network, the buying experience can feel inconsistent some showrooms provide excellent guidance, while others are more limited.
7. J. Sussman, Inc.
- Location: Jamaica, Queens, New York, USA
- Website: jsussmaninc.com
J. Sussman, Inc. was founded in 1906 and is one of the oldest family-owned window and skylight manufacturers in the United States. The company began as a small metalworking shop and has evolved into a specialist in custom architectural aluminum windows, skylights, and bent glass systems. With more than a century of experience, it has built a reputation for handling projects that demand both technical precision and craftsmanship.
Now in its fourth generation of family leadership, the company combines traditional methods with modern technology. Its work appears in churches, schools, and public buildings across the country, with a focus on projects that require custom or non-standard solutions.
Product Range
- Architectural Aluminum Windows: Custom-built to match historic or contemporary facades. These are especially useful for institutional projects.
- Thermal Window Systems: Engineered for better insulation. They help buildings stay efficient in changing climates.
- Skylights: Standard and custom skylights designed for durability and light performance.
- Bent Glass & Metal Work: Specialized service for curved glass and metal framing, giving architects more creative options.
Research & Development (R&D)
- In-House Craftsmanship: Designs are created and refined in their New York facility. That hands-on process is rare today, and it’s something I admire about their approach.
- Specialized Testing: Focus on structural and thermal performance for architectural projects. These tests help avoid costly failures once systems are installed.
- Custom Engineering: Ability to adapt frames, bends, and finishes to specific design requirements. This is practical if you’re working with non-standard dimensions.
- Blending Old & New: Integrates traditional skills with modern machinery. It gives projects the benefit of both heritage and efficiency.
Customer Support & After-Sales Service
Because J. Sussman, Inc. specializes in custom work, communication often feels more personal. You’re not just picking a catalog model you’re working with people who adjust details for your project. The tradeoff is that lead times can be longer, since every order goes through engineering and fabrication before it’s ready.
Final Thoughts
J. Sussman, Inc. is ideal for projects that require one-of-a-kind designs, whether that’s curved glass or historically accurate windows. However, their focus on custom work means they may not be the best fit if you’re looking for standard storefront systems at scale.
8. VEKA AG
- Location: Sendenhorst, Germany
- Website: veka.com
VEKA AG was established in 1967 as a small roller shutter manufacturer in Germany. By the early 1970s, the company shifted its focus to producing uPVC (unplasticized polyvinyl chloride) profiles for windows and doors move that made it one of the largest extruders in the world. Today, VEKA operates more than 40 subsidiaries across Europe, the Americas, and Asia.
Still family-owned, VEKA employs over 6,000 people and produces millions of tons of uPVC profiles each year. Its reach extends to fabricators and installers in more than 80 countries, making it one of the most widely recognized suppliers in the industry.
Product Range
- uPVC Window Profiles: Provide insulation and low maintenance. What many builders appreciate is how these profiles balance cost with reliable performance.
- Door Profiles: Offer stability and weather resistance. They’re used in both residential and commercial settings where durability is key.
- Shutter & Roller Systems: Add shading, ventilation, and security. These are especially common in European homes.
- Sliding Systems: Designed for patios and balconies. They make indoor–outdoor transitions easier while maintaining energy efficiency.
Research & Development (R&D)
- In-House Engineering: New profile systems are designed and tested at VEKA’s global facilities.
- Sustainability Commitment: VEKA runs the world’s largest uPVC recycling plant, giving old frames a second life.
- Energy Efficiency Focus: Profile systems are adapted for thermal performance to meet regional standards.
- Continuous Innovation: Develops solutions for hurricane resistance, acoustic insulation, and modern architectural needs.
Customer Support & After-Sales Service
VEKA works through a global network of licensed fabricators and installers. For buyers, this means local access to products and services without having to deal directly with the manufacturer. The challenge is that service quality can vary depending on the local partner you’re working with.
Final Thoughts
VEKA is best if you want a global supplier of reliable uPVC systems with strong sustainability credentials. However, because they don’t manufacture finished windows directly, you’ll depend on local fabricators for the end product.
Conclusion
Choosing the right storefront window manufacturer isn’t just about glass and frames. It’s about trust, durability, and finding a partner who understands your project.
In this guide, we’ve looked at eight respected companies each with strengths, limitations, and proven histories.
You now know what they offer, where they shine, and why they matter for your build. The “when” is now the earlier you choose, the smoother your project runs.
Ready to take that step? Contact Vallisco today and let’s bring your vision to life.
