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Structural post in concrete: Simpson Strongtie Post base + anchor bolt vs 2x# base with RAMSET?

BMell's picture

Hello Everyone,


Curious about the practice and strength of two methods of affixing dimensional lumber structural beams to concrete slabs in an interior home load bearing wall application.


Simpson strongtie post bases + 5/8" anchor bolts






a dimensional lumber bottom plate and using construction adhesive + ramset fasteners?


Why would i use one over the other? Is it simply just a single post application versus dual posts seperated by a distance and connected on top of a bottom plate? If i'm to have two 4x4 or 4x6's next to each other, seperated by 2", which method is preferred/strongest (earthquake prone LA area!)


Thanks folks!



I don't see any "posts" in (post #214894, reply #1 of 4)

I don't see any "posts" in the second picture.  And the second picture is indoors.

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

You don't fix beams to slabs. (post #214894, reply #2 of 4)

You don't fix beams to slabs. Beams are horizontial framing members, posts are vertical. If you're installing posts to suport a beam over a concrete floor then I'd suggest the ABU44 as they can be installed at any time.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

If uplift is an issue you (post #214894, reply #3 of 4)

If uplift is an issue you need anchor bolts set in the concrete for the base and the nailing schedule for the post in the general notes in the catalog. There is no uplift protection in that second picture but it is probably not necessary on an internal wall unless it is load bearing.


New Construction or Retrofit? (post #214894, reply #4 of 4)

The Simpson product provides greater resistance to withdrawl (uplift) when properly installed in new construction than any powder-actuated kind of fastener.

Keep in mind too with installation of a load-bearing post the slab underneath needs to be sufficiently thick to withstand loads it will have to bear. Retrofitting a loaded post onto a 2" thick slab isn't considered a Best Practice. The alternate anchoring method of a plate under multiple posts will spread a subsequent load but that plate still needs proper anchoring to provide any degree of uplift resistance.