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Pier and beam footing sizing?

Averyholtzclaw

Registered User
Joined
Apr 5, 2022
Messages
4
Location
Georgia
In Georgia here using 2018 irc. Building our own house and nowhere in here does it say anything about footing size, or spacing for a center support beam for a crawl space foundation.

Under chapter 5 flooring it gets into beam spans and footing size but that’s in reference to decks. Am I supposed to use that information? Technically a crawl space is a big deck I guess.

Any help would be greatly appreciated.
 
Yeah I have plans not an engineered set specifying things of this nature. Pretty straight forward one story house with trusses.
 
This is for a deck but it is the same principle just remember your calculations for each footing is based on the tributary loads. which are shown in red.
Minimum loads should be 15 lbs per sq ft dead load (framing materials and floor covering weight) plus 40 lbs sq ft live load ( furniture and people) and a minimum 1,500 lbs soil capacity. If you are using gypcrete or tile in your floor you will probably need to increase the dead load number. Click on the link and see if it makes sense to you.

https://dsps.wi.gov/Documents/Programs/UDC/DeckColumnFootingSizeWorksheet.pdf

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This is for a deck but it is the same principle just remember your calculations for each footing is based on the tributary loads. which are shown in red.
Minimum loads should be 15 lbs per sq ft dead load (framing materials and floor covering weight) plus 40 lbs sq ft live load ( furniture and people) and a minimum 1,500 lbs soil capacity. If you are using gypcrete or tile in your floor you will probably need to increase the dead load number. Click on the link and see if it makes sense to you.

https://dsps.wi.gov/Documents/Programs/UDC/DeckColumnFootingSizeWorksheet.pdf

View attachment 8777
Thank you this is very helpful.
 
Is the pier only supporting the first floor? No load bearing walls carrying other loads? But it's is tributary areas and live and dead loads, and soil bearing capacity.

I am not an engineer but took engineering classes in grad school. I just urge caution. Consider many older houses do sag (I've jacked up one) because the pier footings are too small.
 
Pier Footing Size Minimum 8" deep 16" wide 24" long for 8 x16 CMU blocks
8" deep 20" wide 24" long for 12 x 16 CMU blocks
8" deep 24" wide 24" long for 16 x 16 CMU blocks

Minimum size provides a minimum 4" projection at perimeter of piers.

Note: The projection shall not exceed the thickness of the footing.
 
Pier Footing Size Minimum 8" deep 16" wide 24" long for 8 x16 CMU blocks
8" deep 20" wide 24" long for 12 x 16 CMU blocks
8" deep 24" wide 24" long for 16 x 16 CMU blocks

Minimum size provides a minimum 4" projection at perimeter of piers.

Note: The projection shall not exceed the thickness of the footing.
That 16 x 24 on 2000 pfs soil is just a little over 100 sf of floor - 10 dl and 40 ll - so fine minimums but may be inadequate for loads.
 
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