1

I'm drafting our "forever home" and have enough knowledge of our building code (Ontario Building Code, National Building Code) and I've done enough significant renos that I'm on a solid enough footing (pun intended). I know Autocad and like to do my own designs before handing them off to an architect to review/annotate/stamp both to save some cost dealing with all the invariable alterations to our design, and because I just enjoy it.

The home will be on piers pinned to granite (Canadian Shield). My plan is sono/builders tube footings out of concrete with at least 4 rebar pins per footing, with saddles and posts, braced to their neighbouring piers. The home is a large bungalow with a 72'x48' footprint, and I'm looking at a grid pattern for the piers of 7 (~12' spaced) x 7 (~8' spaced), 49 total. I have a couple questions about the piers and sadles specifically...

  1. I've used this method for smaller buildings, but I'm unsure if this method is right for larger homes...is a standard 6x6 rebar Carport Saddle (i.e. Simpson StrongTie RCPS) rated for this type of application/load?

  2. Are there more suitable saddles I should be considering for either convenience, or otherwise?

I'd appreciate any experience or insights you can lend me, thank you!

1

I don’t think the Simpson RCPS post supports are strong enough for your application.

If the pier supports are 12’ and 8’ on center, then each pier could carry 12’ x 8’ x 40 psf (live load only) = 3840 lbs. (plus dead loads, roof loads, if any, etc.)

However, the RCPS is rated for about 1000 lbs. for 6x6. See chart:

https://www.strongtie.com/nonstandoffpostbases_postbases/rcps_saddle/p/rcps

4
  • Thanks Lee, I should have considered that! Are you aware of any types of saddles that are rated 4k lbs, or is there another method that I should be considering for seating my posts? Is it that I have to go steel piers for this type of application, I've got to believe there's a way to do this with standard lumber on piers?
    – oucil
    Jul 9 at 4:46
  • If I'm reading these correctly, this (strongtie.com/standoffpostbases_castinplacepostbases/epb_base/p/…) elevated cast in place post can carry 3465 lbs, and this (strongtie.com/retrofitpostbases_postbases/cptz_base/p/…) Concealed post tie is good for 19,840 lbs? If so, that answers my question, just hoping I'm reading that correctly.
    – oucil
    Jul 9 at 4:55
  • 1
    Yes, you are reading those charts correctly. However, please be aware that wood crushes differently under loads parallel to grain vrs. perpendicular to grain. Part of picking the correct post base is making sure the post has a large enough base so it does not crush the grain. (Which these do.) When this post connects to the floor beam, be sure it is rated correctly too. The tendency is to crush the beam because it’s taking the load perpendicular to grain.
    – Lee Sam
    Jul 9 at 18:33
  • More great info, appreciate you taking the time! I'll double check what our code requires, and read up a bit more on the topic. Cheers!
    – oucil
    Jul 13 at 21:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.