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. Such was a recent experience when I was looking for a beam for a renovation project. The owner suggested an LVL beam. After explaining what it was and the LVL beam span, I decided to give it a try, but I also wanted more information.
An LVL or laminated veneer lumber beam is made up of thin layers of wood veneer similar to plywood. The layers are heated, glued, and pressed together in different widths or thicknesses, and then cut to depths to meet various load requirements. Depending on its width, depth, and load parameters, an LVL beam can span up to 80-feet.
In this article, we’ll identify what LVL beams are, their different sizes, how far they can span, and their different uses. We explain how to determine beam size and also discuss their cost. Additionally, we look at how to install an LVL beam. Our goal is to provide you with information to help with your next or current building project.
Contents (Jump to Topic)
What Is an LVL Beam?
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. It is made in a similar manner to plywood using softwood veneer logs or peelers.
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”. The veneer sheet is then dried with hot air, causing it to shrink some, and then it is trimmed to size for LVL production.
Once dried and trimmed, the sheets pass through a sander or grinder that flattens and smooths them to a consistent thickness. The veneer then passes through a gluing machine that applies a thin layer of waterproof adhesive. The glued sheets are then stacked with the grain running longitudinally like solid lumber; not alternating longitudinally and latitudinally as with plywood.
The number of sheets in the stack determines the thickness of the laminated beam. The stacks then pass into a machine that produces high heat and pressure to ensure a strong, long-lasting adhesive bond between layers. Since the layers of wood grain all run parallel to each other, LVL is similar to solid wood, but at least twice as strong. LVL is also straighter and of more uniform dimensions than regular lumber, and is less likely to shrink, twist, warp, or bow.
The LVL sheets are sanded smooth on all sides and then cut into widths and lengths based on market demand or special orders. The LVL wood beams are stamped every 4’ with the manufacturer’s name, branding logo, or product identification number and stress grade in accordance with ASTM D5456 or CSA 086. It is then wrapped for shipping to domestic and international locations. The price per piece is affected by the distance shipped, as well as the dimensions of the LVL beam itself.
How Far Can an LVL Beam Span Without Support?
The distance an LVL beam can span depends on its width and depth. Laminated veneer lumber typically comes in 1-3/4”, 3-1/2”, 5-1/4”, and 7” widths or thicknesses, and depths of 5-1/2” to 24”, including standard and nonstandard depths. The lengths commonly range from 4’ to 48’, usually available in 4’ increments. Plus, special orders between up to 60’ or 80’ are available – depending on the manufacturer.
Most building suppliers will carry 8’, 12’, and 16’ lengths and order in longer lengths as required. The length often depends on the manufacturer, with 80’ being available but 60’ or less are more common due to transportation restraints. Beams can be cut to length and notched or drilled at the building site, and double, triple, or quadruple ply is used for strength, the same as dimensional lumber, making it a versatile choice.
The depth of the beam along with its width, combined with common construction variables such as building width, loads, number of stories, joist spacing, etc., determine its span. Whether the span is multiple or a single is also important. As is how it will be used – floor beam, joist, rafter, ridge beam, header, or lintel.
The structural design variables for the beam are vital and vary with the manufacturer. This means trying to compare different products is often difficult, so always check with your local building department or a Structural Engineer. Additionally, if holes need to be drilled through an LVL wood beam, it is recommended that the beam be 3-1/2” or wider.
A 1-3/4” 2.1E 2800 beam with 100% load duration that is 7-1/4” deep will span up to 16’, an 9-1/2” deep will span to 20’, and 11-7/8” deep to 26’. A 14”, 16”, and 18” deep will all span 30’, but 16” and 18” are typically doubled or tripled for greater loads. 3-1/2” 2.1E 3100 at 7-1/4” deep will span 20’, a 9-1/2” up to 26’, and other depths 30’. A 7” 2.1E 3100 at 24” deep can potentially span up to 60’ depending on load and construction variables, and application.
What Sizes Do LVL Beams Come?
LVL beams commonly are available in widths of 1-3/4”, 3-1/2”, 5-1/4”, and 7”. The depth of laminated beams ranges from 5-1/2” up to 24”, which means 1-3/4” widths can be represented as 2×6, 2×8, 2×10, and 2×12 and fit in standard construction fasteners. The laminated lumber is typically available in 4-foot increments beginning at 4’ and running up to 44’ or 48’ in length.
Some manufacturers produce LVL up to 60’ in length, and others up to 80’, however, most stick to 60’ due to transportation constraints. Many home building supply stores carry 1-3/4 widths of LVL wood beams for residential use in 4’, 8’, 12’, and 16’ lengths, and will special order others as needed.
LVL Beam Uses
LVL beams are used for a variety of structural framing and construction purposes, including floor and ridge beams, joists, headers, lintels, rafters, trusses, rim boards, and scaffold planks. Laminated lumber is also used for road signposts, ramps, flange wood for I-joists, and even truck bed decking and skateboards, as well as numerous other uses. Most LVL lumber is for dry interior use, but H3 and other chemically treated laminated lumber can be used outdoors and exposed to various weather conditions.
How to Calculate LVL Beam Size
To calculate the length of LVL beam required, measure from the center of the support posts at each end of where the beam will be placed. Each manufacturer either provides span charts for their LVL products based upon different construction variables, so check the supplier’s site for a span chart. Since LVL design and strength depend on the manufacturer, which is proprietary to that company, and tributary load area and joist spacing affect the load, consulting a Structural Engineer is recommended.
Some manufacturers provide specific values for maximum vertical shear, maximum bending moment, elasticity strength, and weight for calculating beam size. Others provide the information based on the number of stories, the width of the building, live and dead loads, and load duration.
To traverse that distance required, select the beam that best meets your needs. Span charts commonly identify spans for one or two stories, different beam depths, as well as other potential variables and uses; such as floor beam and header for garage, window, or door.
For a floor beam, select the appropriate span table for one or two floors, identify the distance it needs to span, the depth and width of the beam, the span carried by the beam, and the live or total load.
For example, a beam spanning 20 feet and carrying a span of 40 feet with a combined load of 55PSF for 100% load duration, needs to be 5-1/4” wide and 18” deep or 7”x16”. The beam may be a single width or made up of 3or 4 layers of 1-3/4” wide lengths.
How Much Do LVL Beams Cost?
The manufacturing process for LVL beams is more expensive than that used for standard lumber and contributes to the cost of the finished product. The strength rating of the LVL wood beam, its width and depth, along with the length, all affect the cost, as does transportation to the job site and associated installation requirements.
On average, depending on width and depth, an LVL beam will cost between $7 and $40 a linear foot. It should be noted though, that the increased span can decrease other construction costs, making the higher price into potential savings overall.
How to Install LVL Beam
Installing an LVL beam depends upon whether the installation is part of a new build or a renovation. A new build install is much like using standard lumber. The beam is typically supported at each end on exterior walls and may have one or more support posts along its span.
The depth and width, as well as the length, contribute to the weight and may require a crane to lift it into place. The beam may be composed of two or more widths or plies of LVL for lighter lifting, or a solid width up to 7”. Once in place, the beam is leveled and braced, awaiting joist placement.
Installing an LVL in a reno can be much more complicated and messier. Removing drywall or lathe and plaster, rearranging plumbing, electrical, and HVAC are often necessary. It commonly requires one or two temporary “walls” to support the ceiling or floor structure while support posts are placed or king studs installed, and the new beam measured, cut, and lifted into place.
The length of the beam may require opening a section of the exterior wall to allow passage into the location too. Once installed and secured, the temporary “walls” are removed. Using 1-3/4” wide LVL beams is lighter than wider beams, and placing and bolting two or more together provides the same structural support as a wider beam.
Conclusion
The distance an LVL beam can span depends on a plethora of factors. Some manufacturers limit their beams to 60’ due to transportation issues, while others have the capability to manufacture beams up to 80’ long. So, the longest unsupported span possible using LVL would be 80-feet.
Typically, though, it is common for a continuous LVL span to be between 20’ and 30’. Hopefully, you have a better understanding of what LVL beams are and how they may be used on your next project.