September 18, 2019

University of Maine Testing Confirms Remarkable Performance of LP Legacy Premium Sub-Flooring Under Rigorous Jobsite Conditions

Following 14-month, four-phase testing, including repeated wetting cycles and step-load simulations, LP’s premium sub-flooring demonstrated exceptional fastener holding capacity.

NASHVILLE, Tenn. (September 18, 2019) – Since the inception of LP Legacy® Premium Sub-flooring, LP has committed to putting the panels through rigorous, and sometimes extreme, testing beyond industry requirements to truly measure and showcase the product's superior moisture resistance, strength, and stiffness. This mission continued at the University of Maine Advanced Structures and Composites Center, where wood scientists tested LP Legacy panels alongside commodity OSB and plywood in a four-phase, 14-month study designed to simulate the potential extremes of a real jobsite and wear in a finished home.

"Typical tests for OSB look at strength and stiffness; they're usually really quick and can be done in a lab in an hour. But none truly emulate the conditions you're going to see in the real world," says Brian St. German, Director of Technology at LP. "What we're trying to do with this testing is to show builders that this high-performance OSB panel will actually perform better."

The study consisted of four phases:

  1. Fastener holding capacity tested by creating small-scale floors of oak hardwood flooring stapled to the sub-floor and pulled off with a specially designed test jig. LP Legacy offered a 35 % higher withdrawal capacity compared to the other two subjects.
  2. Testers subjected the panels to a simulated rainstorm for eight hours, brought the panels back down to their original moisture content for 48 hours, and then repeated the process two more times. LP Legacy took two and a half times longer to absorb the moisture compared to the other two products, and once again had the highest fastener holding capacity.
  3. For Phase 3, testers simulated seasonal moisture variations that exist in most homes by taking the samples from the Phase 2 wetting cycle, attaching hardwood flooring, and cycling between moisture extremes in a conditioning chamber. After nearly a year, the LP Legacy sub-flooring panels had no significant dimensional changes.
  4. Finally, the panels underwent a 50,000-step-load simulation. Testers looked for floor squeaks, as well as the withdrawal capacity of fasteners after all of the exposures. After four phases of testing, LP Legacy showed no reduction in fastener capacity.

“After all of the exposures, the repeated wetting, the repeated hydrothermal cycling, and the repeated loading, the fastener capacity of Legacy OSB has virtually remained unchanged,” reports Benjamin Herzog, a Wood Technologist for University of Maine who was conducting the tests. 

The tests add to the many others LP has conducted over the past several years to push LP Legacy to the extremes to help prove its worth under jobsite conditions, simulations that are in addition to, and that often have gone far beyond, tests required by the industry standards. LP’s protocols included a Tested Extreme® campaign, which saw LP Legacy panels sent over a waterfall, converted into muddy mountain bike ramps, and submerged as a shark cage.

"What we've seen is there is no degradation of performance," says St. Germain of the latest round of tests. "After final testing, we saw the same level of performance that we did prior to cycling."

Made with Gorilla Glue Technology®, LP Legacy sub-flooring is among the strongest in its class and the industry’s stiffest panel. The panel’s stiffness makes it ideal for hardwood flooring and tile applications, and high panel density provides exceptional fastener holding strength and a quieter floor. And with superior moisture resistance, LP Legacy sub-floor panels carry a Covered Until It’s Covered® no-sand guarantee.

"How your floor feels underfoot, how solid your house feels, that is all dependent on the materials that are underneath the floor," says St. Germain. "So LP Legacy will give you that strong, stiff floor that's going to help maintain a nice, solid, quiet floor system. It is something that a homeowner can see and feel long after they buy the house."

To learn more about the University of Maine testing and hear from the scientists conducting the study, watch this video.

To learn more about LP Legacy and complete warranty details, visit  

Note: The views expressed by University of Maine staff should not in any way be considered to be, and do not constitute or imply, the endorsement, recommendation, or favoring of any particular product.


About LP Building Solutions - As a leader in high-performance building solutions, Louisiana-Pacific Corporation (LP Building Solutions, NYSE: LPX) manufactures engineered wood building products that meet the demands of builders worldwide. Its extensive offerings include innovative and dependable building products and accessories, such as LP® SmartSide® Trim & Siding, LP Structural Solutions portfolio (LP WeatherLogic® Air & Water Barrier, LP Legacy® Premium Sub-Flooring, LP® TechShield® Radiant Barrier, LP® FlameBlock® Fire-Rated Sheathing and more), oriented strand board (OSB), LP® TopNotch® Sub-Flooring, LP® Outdoor Building Solutions®, and LP Elements® Performance Fencing. In addition to product solutions, LP provides industry-leading service and warranties. Since its founding in 1972, LP has been Building a Better World by helping customers construct beautiful, durable homes. Headquartered in Nashville, Tennessee, LP operates 26 plants across the U.S., Canada, Chile and Brazil. For more information, visit