I am planning a new deck and spent a bunch of time searching through the archives and wish to thank everyone for the best advice on the web!
My deck will be 25’ x 15’ and about 44†above grade. I am going to build as a free standing deck supported with two 25’ double 2×10 PT boards, each sitting on 4 piers. The holes will be about 48†deep, bell out the bottom and use an 8†or 10†sonotube as the form. What do you all think of the idea of having the pier about 2’ above grade at the proper level for final construction. I can cut all the tubes at the proper finished height and not have to use any wood posts. The 2×10 PT beams can sit on Simpson ABE44 standoff post base bolted to the pier. The beams will have a ½â€ spacer to allow air between and for proper fit in the post base. I can make minor height adjustments with large washers or metal plates under the standoff as needed. I was thinking of doing the piers this way so I do not need to install any post angle bracing and save some time by not having to cut and install posts and have to connect beam to posts.
I have decided to use Ipe for the deck and railings and am going to use some type of hidden fastener system. The Ipe Clip Extreme fasteners and pregrooved ipe boards from the ipedepot look pretty good. Any experiences with these things? A rough calculation for enough of the stainless deckmasters brackets is $750 and the extra cost for the pregrooved ipe and clips is $610, so not a big difference. Except with one we get to work from above! Is it much of a PIA to install or set a board into the clips? I think a little warp or twist and lining up the clips to the groove is time consuming, not to mention one end popping out as you try to install the board. I guess the Bowrench thing would help.
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Thanks for your ideas and comments.
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Kevin
Replies
How much rebar are you going to put in you concrete piers. Concrete has a lot of compression strength but not a lot of sheer strength. So any cocreate that is out of ground will not take much side pressure (force)
Next problem concrete allows cold to flow so the more of that is exposed to say 36 inches of concrete to air temp of -30° at 50 mph. the deeper the frost is going to go. The more likely you will get frost lift on the piers. That is why most people try and keep the top of concrete pier to with in an four inches of the ground or less.
Thanks for the fast response! I am thinking that 3 pieces of #3 rebar should be OK. We don't get real cold winters, if it is -10/-20 for a week thats real cold for us. Most of the winter is 10 to 25 degrees if that makes any difference. I don't want to have a frost heave problem later on just because of what I am thinking of doing.
Kevin
An 8" concrete pier sticking out of the ground like that sounds a little suspect, just off the top of my head. I'd pour them about 6" above grade and use posts to support the beams. I'd also use 4x as a beam instead of building up 2x. Have you confirmed that your beams are appropriate for the load of the deck? An Ipe deck is going to be HEAVY!
The span calculators and building codes show am I OK. I tend to overbuild things, so 2x10 joists 12" OC with a 13' span and 4x10 or 4x12 beam with 7'6" between posts should spec for 60lb live load. Ipe is about twice as heavy as PT deck boards and close/about the same as Trex and other hardwoods? I see that Pro-Deck uses the 4x lumber for the beam in his constuction in the pictures he has posted so that must be the best way to do it! Since the beam will be 25' long what is the best method for the spilce? Besides making sure it is above a pier! (right?) I guess Simpson makes a connector plate suitable?
Thanks for the fast response
Kevin
I agree that posts above the ground would be better, and would likely be easier.
One thing that you could consider is putting together the rim joist and the beam and shim it exactly where you want it, and then hang the posts right over the center of the concrete. You can then pour the concrete right around standoff posts and be assured that things are perfectly aligned.
Check out the EB-TY Hidden Deck Fastener, it has a lot of "surface holding area", almost twice of what you want to use. Maybe ask your supplier to compare the two and ask them which has more "holding" and or "surface area strength".
Edited 3/23/2005 10:45 pm ET by GESMS
I have looked at the EB-TY and agree about the larger holding area. I think this is why they redisgned the ipe clip with the stainless metal molded into it. I spoke with ipedepot about this and of couse they say this new clip works great and will hold the boards down. I continue to read old posts and the more I read the more undecided I get! Lots of folks have great success with the clips and others have had problems. Seems the method favored is to drill the top of the board, screw and glue in a plug, sand flush. I am going to picture frame the deck with one deck board so these boards and the first and last deck boards will need to be screwed and plugged anyway so I might just do the whole deck that way.
Here is a link about the concrete piers that I found:
http://www.decks.com/articles.aspx?articleid=33
Also, IRC 606.5 says: The unsupported height of masonry piers shall not exceed 10 times their least dimension. So I think it is OK to build the way I was thinking, but again as I continued to read old posts lots of people like to pour a footing 48" below grade and set a 4x4 or 6x6 .60 PT post on the footing and backfill with gravel around the post.
Kevin