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. Glued laminated timber shall be naturally durable or preservative treated with an oil-borne treatment in accordance with AWPA U1.Video can’t be loaded because JavaScript is disabled: What is Laminated Veneer Lumber? (LVL) () Glue Laminated Timber Beams SpansĪssumes 40 psf live load, 10 psf dead load, L/360 simple span beam deflection limit, cantilever length/180 deflection limit. Engineered beams are more expensive than standard deck framing materials but are usually the only option for projects that demand long beam spans. They will also provide a report which will be useful in applying for building permits. They will send your information to a design center where an engineer will specify the proper size engineered beam. ![]() Bring them a plan of your deck with dimensions showing the position of all your footings and posts. Your local lumberyard should be able to help you size and order engineered deck beams. Large, solid sawn lumber timbers, referred to as “heavy timber” are available, but may be expensive to obtain in decay-resistant species if desired or necessary. Parallam beams are manufactured by gluing together aligned wood stands and bonding them using a microwave process. Glulam beams are manufactured by gluing layers of dimensional lumber together. Engineered beams must be treated for use outdoors. It is possible to achieve spans up to 20 feet. These beams are designed much stronger and more stable than standard dimensional lumber beams. Using an engineered beam will reduce the number of posts blocking windows under a deck or may provide a clear span for a deck over a driveway. It is possible to increase your beam spans and eliminate footings and structural posts for your deck by using engineered laminated beams, heavy timbers or steel I girder beams.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |