Should a shear wall be strapped to a chimney?

Question

We are seismically retrofitting our 1951 home. The chimney is in one corner of the garage and both walls abut into the chimney, but neither wall appears to be fastened to the chimney.

• The wall on the left will be built out as a shear wall. Existing framing is tied to the rafters above and also on the back side of the chimney with what appears to be 3/4" solid-wood sheathing.
• The wall on the right contains the garage door.

Should the shear wall be strapped to the chimney, or let the chimney stand on its own and only strap the shear wall to the rest of the wood framing?

Here you can see the left and right walls using the chimney as one corner of the garage:

The chimney pictured above is to the right of this picture below:

In the picture below you can see how both walls come together into the corner above the chimney (old water damage, it's sealed now). At the top-left of the chimney you can see the solid 3/4" T&G sheathing that runs behind the chimney. (The metal rail at the bottom is for the garage door.)

Answer 1

The Code is clear, masonry is not to be supported by wood. Usually this is in reference to vertical loads (headers supporting brick walls, etc.)

For horizontal loads there are other concerns. Bracing supports are not critical load supports.

In your case, straps used to provide additional horizontal support for a brick wall could be acceptable, if you knew where the structural supports are located within the brick wall. Adding straps to a non-structural area of your brick would be more harmful than beneficial and merely tear the brick wall apart under load.

I’d try to strap the bricks together so it has better overall support and not introduce outside forces to the brick.