Would an A-35 be suitable for the rafter>top-plate connection shown here? Would I need one on both sides of a rafter, or just on one side? Existing structure (grey) is 12'x 18', 6" CMU block w/rebar, located in Central California (seismic zone). Essentially putting a new "hat" on the building which will be a small sleeping loft, want to make sure everything is to code, particularly hardware connections. General advice as to fastener/connection details is also greatly appreciated. (i.e. Would simply toe-nailing into the top plate be suitable? Are framing-angles even necessary for transferring horizontal loads/preventing shear in this instance?) Thanks All! Rafter/Top Plate Detail

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Yes, a framing angle such as an A35 is required to transfer the horizontal roof load to the wall and to resist uplift from wind hitting the overhang. (I don’t think an A35n is strong enough.)

I prefer the H1, but one A35 is acceptable. (Two A35 is not required.) Make sure you Install the A35 correctly by bending the tab so the tab can be nailed down into the top plate and sideways into the top plate.

Btw, the top plate on a masonry wall requires a 3” square washer and I’ve never seen then smaller than 5/8” x 10” long spaced a max of 32” oc in your location.

  • 3" sq washer tied into the existing bolts was the plan for TP-Wall connection. Cores of the existing top 2 block layers are hollow though (rebar excluded), wouldn't be difficult to add bolts where necessary? How about the blocking? I was planning on using a LTP4 Tie-Plate to tie the blocking to the top plate, necessary or no? Extremely helpful, btw! Aug 26 '19 at 21:47
  • @LorrinFrench No, the LTP4 will not work. As soon as you drive a nail into the masonry, it will chip out. I’d try URFP or the FRFP , which are designed for retrofit projects. However, please note that they’re really designed for concrete walls, not masonry. So, you could try FJA or FSA foundation anchors, which are mounted further down the wall, but still designed for concrete wall. I’d be remiss if I didn’t tell you to reinforce the top cell. I’m not sure of the stability of the wall. Look through this...start on page 23 embed.widencdn.net/pdf/plus/ssttoolbox/jg8ztjcq8z/C-C-2019.pdf
    – Lee Sam
    Aug 26 '19 at 22:32
  • I was thinking the LTP would be nailed into the top plate, which is bolted to the wall, not nailed into the concrete block. Pics added are of the existing conditions. It’s an old dairy building, probably built in the 1940’s. Structurally it seems pretty rock solid, thing withstood a 6.5 quake no problem back in 2003. Aug 27 '19 at 1:38
  • @LorrinFrench But did it have all that weight on top of it. Hmmm...I see some of the cells are reinforced and there are anchor bolts in those cells...that’s a big plus. If you can bolt into the reinforced cells, that would be best. P.S. Is that a San Juan back there? I miss mine...
    – Lee Sam
    Aug 27 '19 at 2:13
  • It certainly didn't have as much weight, it was a 6:12 pitch w/ 2x4 and corrugated metal, however it did support a rather weighty wire/plaster ceiling. Although, I'm fairly certain it was well overbuilt for what it is. Reinforcing looks to be roughly 50-56" o.c. for the filled cells (there's a little variance because of window/door openings, I'll double check the spacing in the morning). Should be fairly easy to insert a titan bolt or something similar into the filled cells w/o existing bolts. As for the sailboat (?), belongs to my cousin, could definitely use a little TLC! Aug 27 '19 at 4:21

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