Guys I need a little help with my deck. I had decided to extend my deck out to my new above ground pool. It is a 16×20 deck that I am extending about 8 more,feet out. The problem, if it is a problem is I used 4- 10″ sonotubes approx. 4 feet deep near the attachment of the old deck and out to the end of the deck. I inadvertently used the wrong deck post base in the cement attaching the 4x4s in the sonotubes. I have 2 – 2x10s going across the span but there is a little play in the base support. My question is when I frame up the deck will the added weight of the deck give the 4×4 posts more security. I think it will be fine, but if I would have to change the post base I would rather do it now.
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More information is needed. What sort of post bases did you use, and why do you feel they are "wrong"?
How long are the 4x4s, up to the beams?
What is the rest of the structure like? In particular, is there any diagonal bracing of the deck floor, to keep it from racking?
Attached pic
Hope this helps. The bracket I used was the basic post base, but for some reason there is play on it. I am able to move the supports a bit. Only about 3 feet off the ground and I also support with some cross beams it still can move it a bit.
The two ways to keep the deck from wobbling are 1) add "knee" braces to the posts or 2) have some sort of diagonal bracing of the deck surface to keep it from "racking". Generally #2 is preferred, accomplished either by using diagonal decking or by running a diagonal brace under the deck.
I will try the bracing with the cross pattern as you suggested as see if it helps and take a photo. Thank you for your help
How much is a little? If it's really just a little I wouldn't worry about it. A post sitting on a base has very little lateral strength anyway so some movement won't make any difference once you get the structural framing in place. It's not the weight of the deck that matters but the attachment of the beam to the posts then the attachment of the joists to the beam and to the house. If it still makes you nervous run some diagonal braces from the bottom of the posts out to the framing.
Correct
As I was continuing on the deck work, I had placed some pretty heavy boards on top of the deck support and it was literally not moving at all so you were correct.
With that said I do have another question. My deck is going to be around 24' wide. I am doing the deck myself and wanted to see how you guys felt on splices on the deck supports. 1 have 4 sonotubes at the depth of 4 feet with 4x4s about 2 feet in height and using 2x10s on each side connected with carriage bolts. Would it be ok to stagger the joints? I know it would be better to have a continuous run on the supports but not able to do alone. Would the carriage bolts suffice or should I use a different attachment like a nail plate. Thanks in advance
It would be better if the deck beams are sitting directly on the posts. Bolting them to the sides of the posts with carriage bolts is no longer considered acceptable practice in my area.
If you do continue with the bolted arrangement, the splices will require 4 bolts through the posts, 2 for each end of the beam. The bolts will be close to the end of the beams, leading to splits and possible beam failure at that connection..
Have a look at this for current design for code requirements: http://www.awc.org/codes-standards/publications/dca6
Mixed reviews
There has always been mixed reviews on this topic. The notched method has always left some to believe that the amount your notching out will lose the integrity of the strength of the support and others feel that carriage bolts do the same. I personally have done the carriage bolt method on a lower deck is more than suffice being that I dot plan on having a herd of elephants on my deck. I live in the country and not really in need of a permit but it is permitted still. But I do believe the less amount of splices the better. That's for sure.
I've split the difference. Notch the post about a half inch and then attach a piece of 2x below the notch.
Not sure
can you explain that in more detail?
Yeah, I had to think about it myself for a bit, to remember what was done. It was the design of my archy/ex-BIL. The post was notched 1/2", a piece of 2x4 about a foot long nailed just below the notch (in vertical orientation), and then the end of the beam set into the notch, secured with nail plates. The beam (12 feet long) was/is two 2xs with a piece of 1/2" plywood in-between.
Splices are fine. Try to stagger them as far apart as possible and if possible make the splice over a post. We use ring shank nails to keep them together. Once you have it al bolted it won't go anywhere.
Notching is not allowed on 4 x 4 posts at all. Actually the code minimun on poss is now 6" x 6" although yopu can use 8' X 8s instead. Bolting beams to the side of posts is allowed. A good resource is the American Wood Council prescriptive deck building guide.
http://www.awc.org/pdf/codes-standards/publications/dca/AWC-DCA62012-DeckGuide-1405.pdf