Want to learn how to make a wood beam with 2 x 8 boards? By selecting the right kind of lumber and using the appropriate construction materials and methods described below, you will have yourself some strong, wood beams to help support your structure.
Before you start, have a look at the types of timber used in construction.
Overview: Make a Wood Beam with 2×8 Boards
Choose high-strength quality lumber for building beams. A load-bearing beam carries the weight of the structure above it. A good example of a load-bearing beam is often seen in many basements.
A steel or wooden beam runs the length of the house and the ends of floor joists rest on it.

The beam itself is supported at regular lengths by posts or in some cases, by a load-bearing wall. The construction of a wood beam is not complicated or difficult and can be accomplished in a short period of time. “How do I make a wood beam with 2×8 boards?“, you might wonder. Follow these steps to find out!
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Choosing Lumber
Choose beam lumber by species and quality. Standard 2×8 lumber from the local home center may not be adequate for the weight a load-bearing beam supports.

Many building departments will specify that strong lumber such as Douglas Fir or Southern Yellow Pine is used. Select boards of the same length and choose them with building the beam in mind.
Discard boards with large, loose knots or excessive warp. Stack the boards and compare crowns (a slight, natural bend from one end to the other). Each board should be crowned in a similar fashion.
Preparing to Build
Laying out the beam prior to construction. Have a few pipe or bar clamps on hand to help align the board edges as you glue and nail the boards into a beam. Depending on the length, several tubes of quality construction adhesive will be needed.

Cut the tubes of construction adhesive to give a 3/8-inch bead. The adhesive will be applied between boards in a continuous bead along the length of the beam.
Cut the boards if they are going to be cut and make sure all are the same length. Make the beam out of 2×8 lumber to its finished length rather than cutting the beam after it is finished.
Putting the Beam Together
Lay the boards out so the crown is orientated the same way for each board. Apply construction adhesive to the first board in a manner to give it good coverage.
Place the second board on top of the first and apply construction adhesive to that board. Put the third board on top of the second and use the clamps to align the board edges of all three boards.
Place three, 20D nails through the top board into the middle board beginning at one end and placing three more nails every 2 feet. Turn the beam over and repeat the nailing process.
Adding Boards
Beams that support heavy loads will need more than two boards. Three or four boards are very common and five or six boards fastened together can make a beam that will support very heavy loads.
Add more construction adhesive and clamp the next board to the beam to align the edges with the beam. Nail the board to the beam in the same manner as the first three boards were nailed with three 20D nails placed every two feet.
This is how I make a wood beam with 2×8 lumber, and by following these simple guidelines, you will be all set to assemble yours as well.
Credits and References
- Photo by Ronnie B at Morguefile.com
- House Framing 101 – https://extremehowto.com/understanding-house-framing/
I built a 32 foot beam but I made mine out of 2&6 at 16 foot boards. I to put mine together like yours but at each staggered joint I put steel plates and bolted them together. I used them to raise a 34 by 28 foot cabin
I built a beam for a non house application and I used liquid nails, lag bolts in 3 locations and heavy duty decking screws up and down. Nails are good but can back out under load/torsion.