Deck Building 8 - Locating the Foundation Pier Holes Deck Building 8 - Locating the Foundation Pier Holes

Margin of Error: 1”

Most Common Mistakes

  1. Locating hole on top of under- ground pipe or wire.
  2. Not checking plans for exact location of hole.

Flash Player You should get Adobe Flash Player so you can view our video.


With the two outer joists in place you now have a clear outline of the edges of the deck. From this outline you can locate all your foundation pier holes. Check your plans to determine the ex- act locations. Say, for instance, your plans call for two holes, the centers of which are exactly 11 from the wall and 2’ in from the outer edges of the sides of the deck. Then measure out along each of the two outer joists 11’ from the wall, mark the joists, drive nails at those points, and draw a string from joist to joist between the two nails. Now measure 2’ from the outside edges of the joists along the string and mark the string. If there are decorative band joists to be added over the two side joists just installed (see Figure 1 at the beginning of the chapter showing deck components), be sure to allow for these in your measurements. These marks locate the centers of the two pier holes. You can now transfer these marks to the ground, using a plumb bob, and drive in two small stakes. Then mark out for the radius of the pier holes and begin digging.

NOTE: The location of the pier block holes is unique to each deck project. Code enforcement will have some say here, but design is also a factor. Piers are often inset from the sides of the deck to hide them from view. The supporting girder supported by these piers is often inset from the end of the deck a foot or two, because a cantilevered or overhanging deck has a nice visual appeal. In any case, be sure you know where you want the supports before you start to dig.

Got a New Project You're Proud of?

Post it on Your Projects!