This deflection or sag can be visible with an unleveled floor or even cracks in the drywall. Most building codes have allowances for sag, and within those allowances, y ou will see LVL beams sag slightly at 14 feet and longer spans. If you overspan any material, including LVL, you can experience sagging to an extent.Īlways follow the manufacturer’s suggested span requirements, or consult a structural engineer when in doubt. Do LVL Beams Sag?Ī properly sized engineered LVL Beam will have some deflection by nature, but if properly built and installed with crowning up, the deflection makes the beam true and level. LVL is especially a great choice for building houses and buildings with open floor plans due to the more extended manufacturing capabilities.ĭue to the nature of the phenyl-formaldehyde resins used in LVL manufacturing, this lumber is pretty fire-resistant which is another excellent reason to use them in residential construction. LVL beams are a high-quality building product that is an excellent choice for most modern homes. LVL will last longer and stay straighter with the higher upfront cost than the lower-cost option. Expensive – LVL costs approximately twice as much to purchase as standard dimensional lumber.LVL can delaminate if left exposed to the weather and weaken the structural integrity of the building. Susceptible to Damage – In outdoor applications where a beam is exposed to the elements, an LVL is not the best choice.You should never stack other materials on top of LVL wood and only load it in one direction. Uneven Strength – Another downside is that LVL is very strong, but only on one axis, because of the stacking of layers with the grain running in the same direction.If one piece of LVL board has swelled up, then all the other LVL lumber will be the same. LVL wood can swell and shrink with moisture content, similar to sawn lumber, but LVL tends to be uniform in swelling and shrinking. Warping – If not correctly stored, LVL will most likely warp even with the added strength. LVL work for interior and dry location applications. The adhesive on many LVL beams is waterproof, but that glue will start to delaminate with repeated water infiltration, weakening the LVL beam. Strong adhesives are the key to making LVL wood strong, resistant to mold, and resistant to termite infestations.Ī drawback of LVL is it is more susceptible to water damage and rot if it gets wet than traditional lumber. Being a composite, LVL is much less likely than dimensional lumber to twist, warp, shrink, or bow. The days of crooked and warped lumber are in the past. Engineered LVL lumber is made in a factory and is robust, straight, and more uniform than dimensional lumber. Is LVL Stronger than Dimensional Lumber?ĭimensional lumber in today’s market is grown quicker with wider spaced growth rings and is not as strong as it once was. Other manufacturers also make LVL engineered products, and all use similar processes for making engineered lumber. Weyerhauser referred to the product as “Microlam” for two years until then changed it to “Microllam.” Many still refer to Microlam when speaking of Microllam as they are frequently interchanged to identify all types of laminated veneer lumber. Microlam and Microllam refer to the same LVL product. Microlam is a common misspelling of Microllam, a Weyerhauser brand of engineered wood products. They are cut to size, wrapped, and prepped for storage or transportation. The process to get to a finished LVL beam starts with debarking the log, then rotary peeling the veneer to send the sheets to the jet tube dryers to reduce the moisture content to 8-10%.Īfter drying, the manufacturer grades the veneer sheets, gets a resin application, and compresses the sheets until dry. The most common wood used in LVL beams is Douglas fir. During World War II, plywood became an essential war material. There is recorded use by the Chinese, English, French, and Russians well before the 20th century, and it received its first patent in 1856. An LVL engineering process uses multiple layers of thin wood assembled with adhesives.Įngineered lumber was first seen in use as early as ancient Egypt. LVL is typically made in a factory, straighter, more uniform, and stronger than traditional milled lumber. The difference is that plywood changes the grain’s direction with each layer, and LVL keeps the grain direction the same. LVL stands for Laminated Veneer Lumber and is similar to plywood in appearance. Video can’t be loaded because JavaScript is disabled: What is Laminated Veneer Lumber? (LVL) ()
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