Setting Beam Height for Your Deck
Setting beam height - an important step.
Once you have determined the height of the first level of your deck
and installed the ledger board its time to think about setting the
height of the supporting beams. This will allow for proper water flow
away from the house and ledger connection and yet still look good to the
Rule of Thumb
Allow for about 1 inch of slope for every 5 feet of deck projection. So over 10 feet, slope your deck about 1.5 to 2 inches.
Use a Laser or Line Level
Place a 4x4 into the anchor bracket on the concrete pier and lightly tack it in place at vertical to the ground.
Use a line level or a laser and shoot from the top edge of the
ledger board to the 4x4. Mark this spot. It represents perfect level.
Find out how far your beam is from the house and use the rule of
thumb above to calculate how far down the deck should be at that point
away from the house.
In our case the beams were 6 feet away from the house. So the deck
surface should be about 1.25 inches below level at that point.
Decide on Your Beam Detail
In our example we used 2 laminate 2x8s (7.25 inches high) and set the
beam directly on top of the 4x4 post. We also used some metal strapping
and brackets to securely connect the beam with the post.
Starting at the line for perfectly level, measure down the thickness
of the deck boards, joists and the beam itself. Mark this point on the
This is where you will cut your 4x4 posts and since they are only
tacked in place they can easily be removed for cutting. Think about
setting beams so they extend beyond the perimeter of the deck wherever
possible. They can be cut to exact size later on.
Notice how we created a 90 degree corner beam on this deck to accommodate the "bump out" where the joist direction changed.
OK, you have made some great progress! Setting beam height is an
important step in the deck building process. It’s now time to start
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