Hometime Team
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Trans 1) Deck Overview Trans
2) Materials & Tools
3) Preparing Siding for Ledger Board
4) Preparing Ledger Board
5) Attaching Ledger Board
6) Digging Footings & Pouring Concrete
7) Cutting & Raising Posts
8) Installing Beams
9) Installing Joists
10) Installing Deck Boards
11) Building Stairs
12) Installing Railings

Installing Beams

The beams go over the posts directly opposite the ledger board, and together they Installing Beamssupport the ends of the joists.

Beams at the same level as the joists are known as flush beams, and they usually require joist hangers, which are easiest to mark out and nail on before the beam goes up.

You want a beam to have the exact same layout as the ledger board, and the easiest way to do that is to cut and mark the beam before the ledger board goes up.

Dropped Deck BeamOPTION: A beam that is positioned to support the joists from below is known as a dropped beam, and it goes in place without joist hangers, since the joists rest on top of it.

Codes will usually require that beams be double or triple the size of the joists for proper support, and that's usually accomplished by sandwiching 2 or 3 joists together to serve as the beam.

But if you assemble longer beams on the ground, they're difficult to raise on a tall deck. One way to get around that is to raise the beam members one at a time.


Positioning Beams on Posts

Positioning Beams on Posts On a 6x6 post (which is actually 5-1/2 inches square) a triple 2x10 beam will only cover 4-1/2 inches of the top. Set the 1st beam member an inch from the inside edge, to make sure the 2nd and 3rd members end up flush with outside edge.

Toenail the 1st beam member in place to hold it temporarily.

TIP: The ends of a beam can be cantilevered a short distance beyond the post supporting it, which makes the posts less noticeable. Check local codes for the maximum cantilevers allowed.


Installing Rim Joist

Installing Rim Joists

Where the rim joists meet the ledger board (and if it’s a flush beam, where it meets the beam) you may want to use an inside corner bracket.



Checking for Square

If the diagonals are not equal, pry up the toenails holding the beam in place and push the beam down toward the corner with the shorter diagonal. Then re-measure the diagonals to see if that did the trick.

TIP: It doesn't have to be a guessing game on how far you push the beam to get into square. Take half the difference between the two diagonal measurements, measure that far back on the beam from where it crosses the post toward the long corner and then push the beam until the mark lines up over the edge of the post. That should bring it close to square, but re-check the measurements to be sure.

Once the beam and rims are square, toenail the beam back into the top of the post.

Then set in the other members needed to bring the beam to full strength, screwing or nailing the second into the first and the third into the second.

Post To Beam BracketCodes might require more than toe-nailing to connect the beam to the top of the post. Several different pieces of hardware are available, depending on the size of the lumber.




OPTION: Use 1/2-inch lag bolts or carriage bolts to bind the beam members together. On a triple 2x10 beam, the bolts should be at least 5 inches long to get through all 3 members

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