advice pouring concrete peirs and post bases the same hight
stealman
| Posted in Construction Techniques on
I am going to be building a deck that will be very low to the ground. There will be no room for posts between the piers and girder. I am looking for advice on techniques to get all the post bases the same height. I know how to set all my forms at the same height, but I usually pour the concrete above the height of my sona tube and slope the concrete away from the center or away from the post base. Does anyone have any good techniques for doing this?
Replies
Old school?
Use a water level to establish the height of the ends and use a string line. Duct tape a stick on the outside of your sonotube at the finished height on each end (2 on the corners 90 degrees out)
Run your string to establish the height of the others...
... or use a laser.
Assuming you have a level of some sort
the challenge is to keep all the post bases at the same height while the concrete is poured and sets up. Get your girder material on the job, lay out the pier locations on it, and nail all the post bases to it in the correct locations. Set the girder across the top of the forms and then use stakes to get it up to the exact elevation you want, and level as well. Then pour the concrete. I find this type of approach a lot easier than trying to get bases accurate relative to a string line, because the string gets hung up on stuff, the bases sink in the concrete a little, they get out of line, they get rotated, and the whole thing gets fubared. I do pretty well when I just fix them all to some wood, stake the wood up solidly, and pour.
Personally, I'd forget the attempt at precision concrete pour and think shims or some such to make up differences. What happens when one pier shifts/sinks a bit later anyway? I think you are overthinking the concrete being perfectly level and you should consider alternatives like shims or adjustable post/beam bases that hug the top of the pier.
If you have decent batter boards (the grade sticks) and you shoot your string line while the concrete is real green you can make it perfect.
Within the tolerance of any lumber you can buy anyway.