The LP Family of Sub-Flooring UNIQUE TO TOPNOTCH Our RainChannel® notch system helps protect against moisture absorption and edge swell. • Engineered specifically for sub-flooring applications • Designed for strength and moisture resistance • Easy installation • Available in two performance solutions: 250 and 350 Technical Guide LPCorp.
LP® TOPNOTCH® SUB-FLOORING Engineered specifically for sub-flooring applications, LP® TopNotch® Sub-Flooring delivers the strength and moisture resistance you need at a price you can afford. Since climates and building practices vary, we offer two different solutions in the LP TopNotch line. All LP TopNotch products feature a self-spacing tongue-and-groove profile for easy installation, as well as our RainChannel® notch system that helps protect against moisture absorption and edge swell.
The Leading Commodity Tongue-And-Groove Sub-Flooring The Best Value In Durable Sub-Flooring The best-selling commodity sub-flooring, LP® TopNotch® 250 OSB Sub-Flooring is designed for optimum stability in both directions. Used by top builders and carried by leading suppliers, LP TopNotch 250 is backed by a 25-Year Transferable Limited Warranty.
Product Design Capacities The design capacities listed in Table 1 below are based on information from the APA publication Panel Design Specifications and represent capacities for the span rating and performance categories. They do not have to be adjusted for grade. For Structural 1 Grade, it is acceptable to multiply the tabulated capacity by the multiplier in the far right column of the table.
Fastener Properties and Adjustment Tables Dowel bearing strength is a component in fastener yield equations, as found in the National Design Specification (NDS) for Wood Construction. Table 2 below summarizes the dowel bearing strength for nail connections of TopNotch products, using terminology contained in the NDS. The design capacity values apply to panels under moisture conditions that are continuously dry in service, where moisture content is expected to be < 16%.
Builder Considerations for a Better Floor Allow panels to acclimate to the surrounding atmospheric moisture conditions, ensuring the panels are as dimensionally stable as possible before installation and before applying finished floor products. In the event panels become saturated after installation, allow them to dry before reconditioning the surface—sanding swollen ends/edges—before installing finished flooring. Design floor systems to exceed Local Code minimum standards.
Additional Notes When strength axis is perpendicular to supports: - Used 3-span condition formulas for supports ≤ 32˝ oc. - Used 2-span condition formulas for supports > 32˝ oc. - Assume 2x support members for spans < 48˝ oc (actual 1.5˝). - Assume 4x support members for spans ≥ 48˝ oc (actual 3.5˝) When strength axis is parallel to supports: - Used 3-span condition formulas for supports ≤ 16˝ oc. - Used 2-span condition formulas for supports > 16˝ oc. - Assumed 2x support members for all spans (actual 1.
Example of Calculating Uniform Load Problem: Calculate the maximum allowable uniform loads (psf ) for 19/32˝ flooring (span rated a 20 oc) applied with the panel’s long axis perpendicular to supports spaced at 19.2˝. Key Variables and Assumptions - 19/32˝ panel with 20 oc Span Rating - 2X (actual 1.5˝) supports spaced 19.
