interior timber column to concrete concealed connection

[flarchitect]

I'm searching for reference details/ideas for concealing a connection on an interior 8" round timber column bearing on concrete. Client wants an apparent direct wood to concrete connection with no visible fasteners. Column supports loft above.

I keep thinking of a baseplate with vertical fin through the center of the post with throughbolts that are plugged.

suggestions?

thanks.

 

[MiketheEngineer]

Most codes do not allow wood to concrete contact unless separated by metal or use of treated lumber.

That said - check out Simpson (strongtie.com) or USP (USPconnectors.com). You might find something that will work.

 

[msquared48]

Use an embedded bearing plate the diameter of the column with a knife plate and plugged bolt holes as you describe.

Mike McCann
MMC Engineering

 

[RareBugTX]

I like much better the connectors that do not require notching of the wood column. You can just apply some finish to the exposed part of the standard outside connector.While I assume this is a simple residential application, notching members create unnecessary planes of failure.(column)

By the way, plan examiners here in the midwest do not like embedded wood members into concrete or masonry, I think they are right, wood will might eventually get rotten at the bases.

My 2 cents

Rarebug

 

[SgherPE]

More on this topic, Is there a rule of thumb on the length of the knife plate to use and or embedment length formula to apply?
thanks

 

[dik]

I've used a steel base plate with a single dowel in the middle. The dowel extends into the column and into the concrete. Assembly is galvanised.

Dik

 

[msquared48]

If there is no uplift on the wood column dik's solution works fine. Otherwise, you will need thru-bolts, necessitating some form of metal attachment.

And RareBug, regarding the wood bearing on Concrete or CMU in a wall pocket, no problem here so long as it rests on an embedded metal bearing plate and there is a 1/2" air gap all around the end of the member.

Mike McCann
MMC Engineering

 

[RVSWA]

I like Dik's solution and I've often thought that with an uplift condition, perhaps an epoxy product like Simpsons "Crack pak" high viscosity epoxy could be injected into the cavity between the rod and the column. I doubt there is an ICBO report to endorse this...