Lock Out The Elements

Stronger Window & Door Installs Starts Here

OSI gives window and door installers an elite system of products—along with the performance, guidance, and long-lasting protection they need to deliver results built for real-world conditions, not ideal ones.

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Built as a System. Proven in the Field.

Engineered to Work Together

A unified system where flashing, foam, and sealant work as one for tight seals and dependable protection.

Made for Tough Conditions

Long-lasting adhesion and all-weather durability designed for the realities of the jobsite.

Results You Can Rely On

Fewer callbacks, consistent installs, and long-term performance backed by a trusted system warranty.

Real Pros. Real Results.

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“You can tell a job that was done with QUAD Max, because even after 20 years—when it’s time to replace something—the QUAD Max is still in good shape.” 

TYRONE LEE

Chicago North Operations Manager

Feldco

Window & Door Products

All products

OSI® QUAD MAX®

Sealant for window, door & siding applications

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OSI® QUAD® FOAM

Insulation foam for window and door installation

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Request a sample for your next install.

If you want to see how the QUAD® Window & Door System performs on a real jobsite, request a sample pack now.

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The OSI® Certified Dealer Program

We developed the OSI Certified Dealer Program to help you deliver the highest quality installation every time, and build your business. You’ll get a combination of proven product performance, education, and services that ensure a job done right.

15-Year Limited Warranty

Custom-Selected Install Protocols

Certified Training & Education

Get Certified Now

Get powerful insights and information that will keep you ahead of the competition. OSI® delivers relevant articles, technical bulletins, videos and much more. We’re sharing what our expert professionals are observing and learning everyday on the jobsite and in the lab.

North Georgia Tackles Big Challenges with OSI
Evolution of Home Building and Sealants
Foam Insulation: Looks soft. Works hard
Fundamentals of Flashing Tapes

Install With Confidence – Get Ongoing Knowledge and Support From the Professionals at OSI®.

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