Post Cap for Beams, 4x4 to 12x12 Timbers

Which cap for which joint

Pick this cap when the beam sits on the post and carries straight on, or when two beams butt end to end above it. If two beams turn a corner and both stop at the post, that joint takes the corner post cap. If a second beam comes in from the side of a beam that keeps going, it takes the cross post cap. The foot of the same post gets a standoff post base.

Sizes this post cap is made in

• Beam: 3" to 12" wide.
• Post: 3" to 15" wide, measured along the beam.
• Saddle: 5" to 15" long and 5" to 10" tall.
• Straps: 2" to 6" wide and 7 1/2" to 10" long, never wider than the beam.
• Bolts: 3/16" to 1", one size for the whole cap.

That takes in 4x4 to 12x12 timbers, and the beam and the post don't have to match. Sizes move in 1/8" steps. The saddle is made 1/16" wider than your beam and the straps 1/16" farther apart than your post, so the timbers slide in without a fight. The configurator opens on a 6" beam over a 6" post: a saddle 10" long and 7" tall, 3" by 8" straps, and 5/8" bolts. For a beam over 12" or a post over 15", send your sizes through the quote form.

Where the bolts go

Each side of the saddle has a hole 1 1/2" in from either end, along the top. A saddle over 6" tall gets a second row beneath. Each strap has two holes down its middle, 3" apart.

What this configurator won't let you do

The top of a post is end grain, and a bolt too near it can split the wood. So the upper strap bolt always sits at least 3 1/2 bolt diameters below the post's top. On the standard 8" strap that bolt is 3 1/2" down, which is enough for every bolt up to 1". Shorten the strap to 7 1/2" and the largest bolt you can pick is 13/16". The guide explains where the 3 1/2 comes from.

One more limit keeps the part buildable: the saddle has to be at least 7/16" longer than the post is wide, so both straps hang from its bottom plate. And a word of advice: there's rarely a reason to go shorter than the 8" strap unless the cap is only for looks.

Questions

Can two beams meet in one post cap?

Yes, when they meet end to end in a straight line. Make the saddle long enough for both ends to bear on it and take a bolt each. The configurator can't see that splice, so one check is yours: each bolt sits half the saddle's length, less 1 1/2", from the joint. Ask your engineer whether that is far enough from the beams' ends.

Which way do I measure the post?

Along the beam. The straps hang under the two ends of the saddle, on the post faces the beam passes over, and "post width" is the gap between them. The post's other dimension doesn't change the part.

The basics

• 3/16" A36 steel plate, laser cut and welded in our ISO 9001 shop in Texas.
• Holes are cut 1/16" larger than the fastener you choose. Fasteners aren't included.
• Enter your timber's real size, not its name. How to measure a timber.
• Bare steel, or matte black powder coat added in the cart.
• Ships free in the lower 48 states.
• No published load ratings. Ask your engineer, and see what to give them.