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Why LP?

Lasting beauty for your home.

LP® siding and structural solutions are designed to protect your home—offering stunning curb appeal, durable performance and long-term peace of mind.

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LP TopNotch 350 Durable Sub-Flooring

LP® Structural Solutions

LP® TopNotch® 350 Durable Subflooring

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LP® TopNotch® 350 Durable Subflooring is designed for exceptional stability to create a strong, smooth foundation for a variety of finished flooring. We back LP TopNotch 350 Subflooring with a 200-day “no-sand” warranty and a 50-year transferable limited warranty.

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Elevate Your Build

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Trust the consistent quality and superior performance of LP® TopNotch® 350 panels and ensure a durable, resilient foundation for all your projects.

Elevate Structural Stability

Benefits of LP® TopNotch® Subflooring

Used by top builders and carried by leading suppliers, LP® TopNotch® 350 Durable Subflooring is designed for stability in both directions and is sanded to provide a more uniform thickness.

Performance

Incredible strength, stiffness and moisture resistance.

Easy Installation

Self-spacing tongue and groove design speeds installation.

Innovation

Designed for elevated moisture resistance.

RainChannel® Technology

Unique RainChannel® notch system to help drain rainwater away during construction.

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Warranty Information

LP® TopNotch® 350 Warranty

Our products are backed by industry-leading warranties.

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Resources for Professionals

Related Products

Some things just work. Others work as one.

From siding to sheathing, our products aren't just designed to be strong on their own, but to be stronger, together.

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