Uneven Concrete Footings for a Deck
NoTalent_AllThumbs
| Posted in Construction Techniques on
Hi,
I poured a couple of concrete footings (8- and 10-inch diameter) for an outdoor deck, that go about 4 feet deep. I did the work in a rush and now I am regretting it!
The tops of the footings (where the wood posts will sit) are not level and it seems I am left with a couple of options (other than redigging)
- Cut the tops of the wood 4 x 4s at an angle so that while the posts itself are not plumb, the tops of the posts will be level to allow the beams to rest on them properly.
I don’t like this idea so much because the posts itself will not be plumb, and I assume this will affect their ability to support the deck. - Somehow, level the tops of the concrete footings – I guess I can either:
– “Cover” the current footings with wider tubes (i.e. 12 inch diameter) and then fill those with concrete and ensure that these are level – I don’t know if this is a good idea because these wider forms would just be sitting on the ground and would not be deep underground like the original forms
– “Stack” the current footings with a narrower tube (i.e. 6 inch diameter) and then fill those with concrete and ensure that these are level – In this case will the new wet concrete properly stick to the dry concrete?
– “Stack” the current footings with a tube of the same width and then fill those with concrete and ensure that these are level – In this case will the new wet concrete properly stick to the dry concrete?
Do you think that any of these options are feasabile? Are there any other fixes that you would suggest or should I just bite the bullet and redig?
Thanks for your help!
Replies
Is this a trick question? Stop! Do not proceed with either option put forth in the question! Your posts must be plumb. Without plumbness of posts, deck will come down during first 100-person deck-hosted karaoke jam. Lawsuits would follow. If this is a deck off of the second floor of a house, you should consult a friend who is familiar with deckbuilding. Are your footing tops at or near ground level? Near the ground is better unless you are planning to do some kind of stone veneer on your piers, or if you have located them in mud. The fact that they go four feet down is good. What you can do is cut the bottom of posts, making sure the posts are plumb. Use a short level to get an idea of how the concrete tops are pitched. If working alone, set an over-long post on top of a pier and hold it plumb with a quick clamp or two holding your level to the post. Measure with your tape to see how much your cut will need to be skewed to get maximum surface area in contact with the pier. Do this for all other posts and make the skewed cuts with a circular saw. You need to have a good mechanical fastening between your posts and your piers. This is true even when your post tops are plumb. If you can't handle the saw cuts described above, and the tops of your concrete piers are not pitched like an Olympic ski mogul run, you can probably just use a Simpson-type 4x4 post base. Tweak the uprights and follow the instructions on fastening the pier to the base to the post. The post will bear fine even if it is a little out of jive with the base. If your footing does look like a mogul run, rent a 16 -inch gas-powered all purpose saw with a diamond blade on it and cut those piers level. Just watch out for all those thumbs!
Revision
I just left an extended response to your inquiry and then re-read your question, and I think I understood it wrong. I now think that you are saying that your concrete piers stick up rather high out of the ground and are out of plumb vertically. I at first took you to mean that just the top surface of the pier is out of level (if this is the case, return now to first response).You say that they "go about four feet deep." If they go four feet deep in the ground and don't stick up out of the ground like three or four or ten feet, you're ok with being a little out of plumb. If they are four foot in the ground and do stick up 3,4, or ten feet and are wildly out of plumb you will probably have to start over. I hope any of this was a help. Good luck.
I am assuming that the footings are plumb, but not level. If that's the case, and you are using the metal post connectors that bolt to the footing, you don't have a problem. I'd just level the top where the connector sits with some patching concrete.
If you were just planning to have the post set on the concrete, that's not a good idea anyway, but the patching concrete would stick to the foundation concrete just fine.
It doesn't hurt if the piers are not perfectly plumb or the tops not perfectly level. You should use metal post-to-pier brackets that allow you to plumb up the posts (and which keep the wood away from direct contact with the concrete). If the tops of the piers are too unlevel for the brackets, you can level them off with some sort of concrete patch. (I'd use thinset, but others here think I have a thinset obsession.) When you make a patch of this sort, if the surface isn't rough enough to give a thick patch good "tooth" you can drill some holes and install concrete screws sticking out a bit, to give the patch something to bind to.
'Nother option
Along the lines of MarkH and DanH's replies.
You never mentioned how high your piers are above grade. If you have at least an inch or so extra.........
I would be inclined to grind the tops of your existing piers to level. Keep in mind they do not have to be perfectly smooth. Any hieght issues can be easily dealt with by varying the post hieghts.
A 7" (or even a 4-1/2") diamond grinding cup would make pretty short work of this project with no potential bonding issues to deal with.
Take some away rather than adding.....
Jim
You tend to be overreacting to your situation.
I assume your footings are reasonably plumb, but the top isn't quite level.
Your posts should be perfectly plumb regardless of whether you cut a slight angle to set on you concrete or shim it as others have mentioned. You have a post bracket in your concrete, right? ... or how are you 'connecting' the post to the footing?
Level footings for a deck
means either 1) level with one another in relatioship to how long your support posts must be or 2) the top surface of the footing itself isn't level. Here's a brief rundown for both scenarios...
In situation 1), it won't matter if you follow this process. Get your band board attached to the house so you'll have a reference for the finish framing height of the deck. Next, take two joists and set one at each end with a temporary post to support it off the ground at the pitch you want to leave in the deck. You can square these to the band and get another piece of scrap to tack in a diagonal to maintain square. Once these two joists are temped in, set in one or two itermediate joists across the deck with their own temporary posts. Measure out from the band to locate where your beam will be sitting and snap a line on the existing joists you have temped in for a reference. Take some 2x2 long enough to account for the width of the joist and the width of the beam and attach to where the excess hangs plumb below the joist. Attach your first beam material to these 2x2's until you have a line for the beam material from one end of the deck to the other. Build out your beam staggering your layers and crowned appropriately. Now all you have to do is measure off the bottom of the beam to the suface of whatever your posts are attaching to on the footings for the actual length of the deck posts.
In situation 2) you could level the surface of the footing itself if it's really out of level badly or you could just make it up in a cut you could scribe to the footing using situation 1)'s process. In either case, it's not a serious issue but as others have said, the posts need to be plumb.
Hope this helps...
Note that NoTalent hasn't put in an appearance since his initial post.
It's a simple fix. Just grind the footing level where the base will go and bolt it in. Cut your post square at the bottom and plumb it up.
I didnt read everyones reply so im sticking myneckout here, but if it were me from what i think youre saying: Drill down through the center of your layout with a hammerdrill 3/4 in. bit about 7 inches down (make sure you drill down plumb) then pump it with simpson epoxy and use a 4x4 post base with the bolt through the center (or 5/8 allthread). Then just plumb up your posts. But you could grind down the tops first .
Keeping your footing's plumb and square
The most important part of your construction project is a good footing. Keeping those forming tubes plumb and square is difficult even for the most experienced contractor. The major problem when using cardboard or plastic forms is making sure that the base of those tubes are equal in distance from one to the other in relationship to the top. When you drop a tube in the hole you have no idea where that base lye's in relationship to the next tube To solve that problem the top of all tubes need to be tied together first, making sure that your center-lines from tube to tube are all equal based on your plan, to do this we recommend using a tool called Plumbatube, this 360 degree tool slides over the tubes which has built in brackets to accommodate 2x4 inch braces, the braces would be cut to a length based on your center-line requirements and temporarily attached using truss screws. You would then check your diagonals stake your corners to grade, now the tops of the tubes are square to each other locked in place. Now is the time to plumb the bases using your level while back-filling. Now pour your concrete to your predetermined height into the tubes, let set up, remove your Plumbatube tools and braces for your next job.Now your post and or beam structure should fit perfectly. See more detail @ plumbatube.com. hope this information helps on your next installation. George
George
Pretty slick tool.
And b/4 someone mentions paying for an ad here on the forum to sell your product, let me thank you for not spamming the XXXX out of the reply and showing something here that could very possibly be useful fo someone undertaking this type of job.
The original poster could have certainly used it.