![]() LVL is also straighter and of more uniform dimensions than regular lumber, and is less likely to shrink, twist, warp, or bow. Since the layers of wood grain all run parallel to each other, LVL is similar to solid wood, but at least twice as strong. The stacks then pass into a machine that produces high heat and pressure to ensure a strong, long-lasting adhesive bond between layers. ![]() The number of sheets in the stack determines the thickness of the laminated beam. The glued sheets are then stacked with the grain running longitudinally like solid lumber not alternating longitudinally and latitudinally as with plywood. The veneer then passes through a gluing machine that applies a thin layer of waterproof adhesive. Once dried and trimmed, the sheets pass through a sander or grinder that flattens and smooths them to a consistent thickness. The veneer sheet is then dried with hot air, causing it to shrink some, and then it is trimmed to size for LVL production. The logs are debarked, pressure steamed with a mix of water vapor and chemicals for 48-hours, and then run through a veneer peeler that ‘unrolls’ the log into a continuous sheet with a thickness between 1/16” and 1/4”. It is made in a similar manner to plywood using softwood veneer logs or peelers. LVL or laminated veneer lumber was used to make propellers for aircraft in WW2 but didn’t become a construction material until the mid-1970s. How Far Can an LVL Beam Span Without Support?.Our goal is to provide you with information to help with your next or current building project. Additionally, we look at how to install an LVL beam. We explain how to determine beam size and also discuss their cost. In this article, we’ll identify what LVL beams are, their different sizes, how far they can span, and their different uses. ![]() Depending on its width, depth, and load parameters, an LVL beam can span up to 80-feet. The layers are heated, glued, and pressed together in different widths or thicknesses, and then cut to depths to meet various load requirements. After explaining what it was and the LVL beam span, I decided to give it a try, but I also wanted more information.Īn LVL or laminated veneer lumber beam is made up of thin layers of wood veneer similar to plywood. Such was a recent experience when I was looking for a beam for a renovation project. With the purlin/bracing installed, the long rafter span would be broken into two shorter spans, thus allowing the rafter to carry additional load.īefore you decide on lumber sizing and span, consult your local building code officials to determine design loads for your area.Every time I wander through my local lumber store, I seem to encounter a new product, not that it’s all that new, just to my awareness or my location. You can break up a long span of rafters by installing a purlin and bracing on the underside. When calculating the span of joists or rafters, use the horizontal distance between vertical supports. The number 1 grade material is more expensive than the #2 grade, but if you can use fewer or smaller number 1 grade joists or rafters in your design, you may actually save money.ĭepending on the availability and cost of various size framing materials, it may be more economical to use larger joists or rafters in your design because you can typically use fewer of them. For example, you can span a #1 grade (no knots) southern yellow pine joist a greater distance than a #2 grade of the same species (with knots). The lengths and sizes of joists vary depending on the species and quality of the lumber used. To calculate maximum spans of additional species of lumber, use the Span Calculator or the Span Tables for Joists and Rafters on the American Wood Council website.Ĭonsiderations when using the Rafter and Joist Span Tables Contact your local building code officials to determine the building code for your area. Weigh all of the elements when designing wood structures. Some areas have wind and seismic conditions. For example, some localities get large amounts of snow, whereas others get none. Before determining the maximum spans for joists and rafters, you must know the load requirements for your region.
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