Supports
Back to Decks
STEP FIVE: SUPPORTS
At this point the frame is done and you have installed temporary supports in several areas to make sure the deck isn't going anywhere. If you have not squared the deck frame, do so, and tack a piece of lumber under the frame at an angle to hold it square.
There are a couple of methods to support your deck, and we will go through each one so you can choose the method most suitable to your project
Girder Beam: This method allows you to cantilever the deck.
Cantilevering a deck gives it a very nice appearance, and moves the supports back a little
to allow more movement in front of the deck. This is one of the easiest methods to line up
the footings with the deck.
Building this system: This is a very simple system
to build. By now you have figured out how many footings you need to support the outside of
your deck. For this system you can use a 4x4 or a 4x6.
1) Measure from the bottom of the frame to the top of each footing and cut each post. If
you are using post feet or another type of anchoring system, attach or set them now,
following the instructions you received with that product. For right now only set the two
outside posts ( if you have more than two ). If you are not using any of these products
and simply standing the post on the concrete footing, that's ok too!
2) Now you need to cut the lumber for the frame. If you have 7' or less between the
footings then you can use 2/ 2x8's as the beam. I almost always use two 2x10's no matter
what the span. I think it looks better and it is defiantly not going to have any bounce.
Corner supports: This is the typical application you will usually see.
Building this system: This is the standard system that you have probably seen on most decks. Corners used to be supported with a 4x4. Now it calls for a 4x6. After notching the post you are left with the equivalent of a 4x4, which is the requirement. We will be notching toward the outside header on the frame ( this piece carries the load of all the joists therefore we need to support that one versus the side of the box).
1). Your deck should be
supported with temps and the footings installed and dry.
2). Place the 4x6 on the inside of the frame in the corner. If you are looking at the outside of the deck frame the thin side of the post should be facing you ( the 3 1/2 inch side ) Plumb both sides of the post.
3). Mark the bottom and top of the frame onto the post with a pencil.
4). Now you want to cut along these two lines to the depth of the framing lumber ( usually
1 1/2" or 1 5/8" ). Set
your circular saw at that depth and cut across the post. Multiple cuts in between these
will allow you to clean
out the cut with a chisel.
5). Place the post back on top of the footing and tap it into the post 'til the outside is flush with the frame.
6). A couple of lags ( at least 3 1/2") can be drilled and set from the outside going into the post.
NOTE: Anywhere you have a footing the post can go all the way down. In a span where a footing is not necessary but that you need a post to carry the rail, use carriage bolts to secure a smaller post to the frame. Add blocking on either side to reduce movement in the railing.