josta
Structural
- Apr 28, 2005
- 28
Got an issue with the local friendly plan check engineer: When retrofitting an existing 2x sill plate where a 3x sill is required I add another 2x member on top of it, tight-fitting between studs ("pressure blocks"). I also edge nail the shear panel to both the existing sill and the new 2x member, plus I face nail (or staple, to prevent splitting) the new member into the existing sill, so that they all perform as one piece; akin to but even stronger than 2-2x members allowed in lieu of a 3x edge stud.
I then show the retrofit anchor bolts to go through both the new and existing sill.
The plan check engineer does not feel that it would perform as one piece; he is concerned about any horizontal shear between the two members, even though the shear panel is edge-nailed equally to each of the two members at the nailing required for the load. In other words, if the load is 490 PLF and 3" o/c nailing is required, I use 3" o/c nailing into each of the two members.
My thinking is for that to not work, the edge nailing at the new and/or existing sill would have to fail.
I realize there is a now-closed thread on this subject, but the horizontal shear issue was not addressed there, nor was the anchor bolt issue addressed as below.
He is also insisting that if this was allowed, that we have two anchor bolts in each stud bay due to the new, shorter 2x member. I say this is not necessary because the purpose of having two anchor bolts per piece of sill is to prevent rotation of the sill about the vertical axis of the anchor bolts, and in this case since the two members are nailed tightly together it is not likely to occur.
I use this method with an addition where it is not possible or practical to make the addition "free-standing" with its own four walls and footing.
Any comments/suggestions? Thanks!
John
I then show the retrofit anchor bolts to go through both the new and existing sill.
The plan check engineer does not feel that it would perform as one piece; he is concerned about any horizontal shear between the two members, even though the shear panel is edge-nailed equally to each of the two members at the nailing required for the load. In other words, if the load is 490 PLF and 3" o/c nailing is required, I use 3" o/c nailing into each of the two members.
My thinking is for that to not work, the edge nailing at the new and/or existing sill would have to fail.
I realize there is a now-closed thread on this subject, but the horizontal shear issue was not addressed there, nor was the anchor bolt issue addressed as below.
He is also insisting that if this was allowed, that we have two anchor bolts in each stud bay due to the new, shorter 2x member. I say this is not necessary because the purpose of having two anchor bolts per piece of sill is to prevent rotation of the sill about the vertical axis of the anchor bolts, and in this case since the two members are nailed tightly together it is not likely to occur.
I use this method with an addition where it is not possible or practical to make the addition "free-standing" with its own four walls and footing.
Any comments/suggestions? Thanks!
John
