Driven or Augured Wood Piles for Residential Plumbness Tolerances 1

[Ron247]

I am looking for advice on the plumbness to expect for wooden piles used to support residences. The wooden columns can be round or rectangular. They can also be driven or have the hole excavated/augered.

These piles do not have pile caps. The wood floor beams are attached to the piles. I have found some as bad as 2" on a 6' height.

I am also curious about alignment of say 5 columns in a row. How much is reasonable for them to be out of alignment.

 

[SlideRuleEra]

These piles do not have pile caps. The wood floor beams are attached to the piles. I have found some as bad as 2" on a 6' height.
I am also curious about alignment of say 5 columns in a row. How much is reasonable for them to be out of alignment.

For driven piling, a common alignment tolerance is 1/4" per foot (2%), but that would still be 1 1/2" misalignment on a 6' height.

In practice, the pile driver adjusts his means & methods by using an elevated template to align pile tops instead of striving for "perfectly" aligned piling.

On the southeast USA coast, houses on piling are common because of hurricane storm surge (flooding) requirements:

FEMA 499 Pile Design & Installation addresses this:

As bridge contractor, we did not drive residential piling but used a heavier, similar template to ensure alignment of pile tops for elevated bridge bent pile caps. This is a photo from one of our jobs:

http://www.SlideRuleEra.net

 

[Ron247]

Thanks for the information SlideRuleEra.

Would you expect the same tolerance on an augered pile where someone augers the hole and then sets the timber as compared to driving the timber? I would assume the augered timber would be expected to be more plumb than a driven one.

The one I am looking at has at least 2 piles in the line that out of plumb more than all others. They are out a similar amount in the same direction and they are adjacent to each other.

 

[SlideRuleEra]

Ron247 - Augered holes have similar alignment tolerance as driven piling. Just setting a pile in an augered hole and calling it quits is not good practice. Where I work, the augered hole should be somewhat smaller than the pile. Then the pile is set and driven; driving continues until the pile tip is lower than the bottom of the augered hole.

Unless steps, such as a pile driving template, were used I would not expect a pile in an augered hole to have a tighter tolerance than a pile that was only (correctly) driven.

http://www.SlideRuleEra.net

 

[Ron247]

Thanks again SlideRule