Load Bearing Wood Beam

On longer spans the beam may require much more bearing space as indicated by this table.

Load bearing wood beam.

The decision was made to install a beam that would span the entire kitchen without posts and be recessed in the ceiling. The client had an existing wood beam with two posts connected to his kitchen island and didn t like seeing the posts. According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2. This header must carry x pounds per lineal foot.

Beams of more than one ply must be fastened together with either nails or bolts. The span of a beam is dependent on a few variables. A load bearing wall almost always has ceiling or floor framing running perpendicular to it. Add up all the loads acting on a header or beam and then translate this load into terms of how much load each lineal foot of header or beam will feel.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. It is important to remember though that while the beam carries the load of the ceiling above all that load is then transferred at the ends to vertical post structures created by a. If you re unsure ask a building contractor or your local building inspector for advice. Fewer posts on upper level decks are typically more desirable to the occupants and this drives the use of larger framing materials for longer spans.

Anything 5 and above we always at least double cripple. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Beam span maximums are based on a maximum anticipated live load. Replacing a load bearing beam with a flush beam was our mission last week.

The species of lumber size of lumber and the load it carries. This translation is the key to any structural sizing. If it s a load bearing wall the inspector may help size the beam or recommend that you have a structural engineer or architect size it. The first step is the same for sawn and engineered wood materials.

A dense wood that bears weight on the ends of those fiber bundles like a stump does can achieve the load carrying capacity of structural steel. Wood gets its strength from its longitudinal cellulose fibers. Two 2 by 4 beams together would not be enough. A 2 by 8 beam would be sufficient.

The formula for the section modulus is beam width times beam depth squared divided by 6. A two 2 by 6 standard beam has actual dimensions of 1 5 by 5 5 inches which would give a section modulus of 1 5 x 5 5 x 5 5 6 7 6 which is not enough for this example.